U.S. patent application number 16/518698 was filed with the patent office on 2020-01-09 for imaging system for screening and diagnosis of breast cancer.
The applicant listed for this patent is Banpil Photonics, Inc.. Invention is credited to Achyut Kumar DUTTA.
Application Number | 20200008682 16/518698 |
Document ID | / |
Family ID | 67300618 |
Filed Date | 2020-01-09 |
![](/patent/app/20200008682/US20200008682A1-20200109-D00000.png)
![](/patent/app/20200008682/US20200008682A1-20200109-D00001.png)
![](/patent/app/20200008682/US20200008682A1-20200109-D00002.png)
![](/patent/app/20200008682/US20200008682A1-20200109-D00003.png)
![](/patent/app/20200008682/US20200008682A1-20200109-D00004.png)
![](/patent/app/20200008682/US20200008682A1-20200109-D00005.png)
![](/patent/app/20200008682/US20200008682A1-20200109-D00006.png)
![](/patent/app/20200008682/US20200008682A1-20200109-D00007.png)
![](/patent/app/20200008682/US20200008682A1-20200109-D00008.png)
![](/patent/app/20200008682/US20200008682A1-20200109-D00009.png)
![](/patent/app/20200008682/US20200008682A1-20200109-D00010.png)
View All Diagrams
United States Patent
Application |
20200008682 |
Kind Code |
A1 |
DUTTA; Achyut Kumar |
January 9, 2020 |
IMAGING SYSTEM FOR SCREENING AND DIAGNOSIS OF BREAST CANCER
Abstract
This invention provides a non-invasive diagnosis system that is
not only capable of producing high-resolution, three-dimensional
images of abnormalities of tissue growth inside the body but, it
can also detect the type of abnormalities and their location using
multispectral imaging techniques. It is possible to provide a
portable, non-invasive device that is handheld and with which women
may use to screen themselves for early detection of breast cancer
without the need to visit a physician. As the present invention
uses broadband sources and/or multiple coherent sources, secondary
factors such as oxygen metabolism or blood volume associated with
the cancer tissues could also be detected to provide further
verification of the type. This invention would raise the accuracy
of diagnosis and reduce the rate of false positives and false
negatives.
Inventors: |
DUTTA; Achyut Kumar; (Santa
Clara, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Banpil Photonics, Inc. |
Santa Clara |
CA |
US |
|
|
Family ID: |
67300618 |
Appl. No.: |
16/518698 |
Filed: |
July 22, 2019 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
14984717 |
Dec 30, 2015 |
10357162 |
|
|
16518698 |
|
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61B 5/4312 20130101;
A61B 5/708 20130101; A61B 2560/0425 20130101; A61B 5/0013 20130101;
A61B 5/0091 20130101; A61B 5/7246 20130101; A61B 2562/066 20130101;
A61B 5/742 20130101; A61B 2562/164 20130101 |
International
Class: |
A61B 5/00 20060101
A61B005/00 |
Claims
1.-20. (canceled)
21. A method for detection of breast cancer using a user device,
the method comprising: emitting an optical signal via a light
source of the user device, the user device having a cavity
configured to at least partly enclose a tissue of a user; enabling
interaction between the emitted optical signal and one or more
portions of the tissue, the interaction producing one or more
returning optical signals; detecting the one or more returning
optical signals via one or more light detectors of the user device;
comparing an optical characteristic associated with each of the one
or more returning optical signals with one or more optical
characteristics corresponding to an interaction with breast tumor
cells; based on a determination that a correlation exists between
the compared optical characteristic and the one or more optical
characteristics corresponding to an interaction with breast tumor
cells, determining a position of at least one of the one or more
portions of the tissue.
22. The method of claim 21, wherein each of the light source and
the one or more light detectors is disposed between an inner wall
and an outer wall of the cavity.
23. The method of claim 21, wherein the comparing of the optical
characteristic associated with each of the one or more returning
optical signals with the one or more optical characteristics
corresponding to the interaction with breast tumor cells comprises
determining a match between a wavelength associated with each of
the one or more returning optical signals and one or more
wavelengths corresponding to the interaction with breast tumor
cells.
24. The method of claim 21, wherein: the emitting of the optical
signal comprises emitting the optical signal from an inner wall of
the cavity toward an inner portion of the cavity and toward the
tissue of the user; and the detecting of the one or more returning
optical signals comprises detecting the one or more returning
signals coming from the inner portion of the cavity.
25. The method of claim 21, wherein the interaction between the
emitted optical signal and the one or more portions of the tissue
comprises reflection of the emitted optical signal from the one or
more portions of the tissue.
26. The method of claim 21, wherein the interaction between the
emitted optical signal and the one or more portions of the tissue
comprises diffraction of the emitted optical signal from the one or
more portions of the tissue.
27. The method of claim 21, further comprising causing rendering of
an image based on the one or more returning optical signals.
28. A user apparatus for detection of breast tumor, the user
apparatus comprising: a curved cavity having an inner surface and
an outer surface, the curved cavity being configured to at least
partly enclose a tissue of a user; a light emitter disposed between
the inner surface and the outer surface of the curved cavity, the
light emitter being configured to emit a plurality of optical
signals from the inner surface toward an inner portion of the
curved cavity; a light detector disposed between the inner surface
and the outer surface of the curved cavity; a processor apparatus
configured to cause the user apparatus to: emit an optical signal
toward the tissue of the user via the light emitter; cause
interaction between the emitted optical signal and one or more
portions of the tissue, the interaction producing one or more
returning optical signals; detect the one or more returning optical
signals via the light detector; determine a location of a malignant
portion of the tissue based on a correlation between (i) an optical
parameter associated with each of the one or more returning optical
signals and (ii) one or more optical characteristics corresponding
to breast tumor cells.
29. The user apparatus of claim 29, wherein the correlation between
(i) the optical parameter associated with each of the one or more
returning optical signals and (ii) the one or more optical
characteristics corresponding to breast tumor cells comprises a
match between (i) a wavelength associated with each of the one or
more returning optical signals and (ii) one or more wavelengths
corresponding to interaction with breast tumor cells.
30. The user apparatus of claim 29, wherein the correlation between
(i) the optical parameter associated with each of the one or more
returning optical signals and (ii) the one or more optical
characteristics corresponding to breast tumor cells comprises a
match between (i) a spectral pattern associated with each of the
one or more returning optical signals and (ii) one or more spectral
patterns corresponding to interaction with breast tumor cells.
31. The user apparatus of claim 29, wherein the inner surface
comprises a surface area associated therewith, the user apparatus
being configured to enable adjustment of the surface area based on
a distance between the inner surface and the tissue of the
user.
32. The user apparatus of claim 29, wherein the interaction between
the emitted optical signal and the one or more portions of the
tissue comprises at least one of diffraction or reflection from the
one or more portions of the tissue.
33. The user apparatus of claim 29, wherein the processor apparatus
is further configured to produce three-dimensional image based on
the one or more returning optical signals.
34. The user apparatus of claim 29, wherein the light emitter
comprises a plurality of light sources, and the optical signal
comprises a broadband optical signal associated with a range of
wavelengths.
35. A system for detection of breast cancer, the system comprising:
a receptacle configured to at least partly receive a volume of
tissue of a user; a light source and a light detector embedded
within the receptacle; and a processor apparatus configured to
cause a user device to: produce, via the light source, an optical
signal emitted toward the volume of tissue of the user; detect, via
the light detector, the one or more returning optical signals from
the volume of tissue of the user subsequent to an interaction with
the produced optical signal with the volume of tissue of the user;
determine a position of a malignant portion of the volume of tissue
based on a comparison between (i) an optical parameter associated
with at least some of the one or more returning optical signals and
(ii) one or more optical characteristics correlated with an
interaction of an optical signal with malignant breast tissue.
36. The system of claim 35, wherein the comparison between (i) the
optical parameter associated with the at least some of the one or
more returning optical signals and (ii) the one or more optical
characteristics correlated with the interaction of the optical
signal with malignant breast tissue comprises a comparison between
(i) a wavelength associated with the at least some of the one or
more returning optical signals and (ii) one or more known
wavelengths correlated with the interaction of the optical signal
with malignant breast tissue.
37. The system of claim 35, wherein the comparison between (i) the
optical parameter associated with the at least some of the one or
more returning optical signals and (ii) the one or more optical
characteristics correlated with the interaction of the optical
signal with malignant breast tissue comprises a comparison between
(i) a spectral pattern associated with the at least some of the one
or more returning optical signals and (ii) one or more known
spectral patterns correlated with the interaction of the optical
signal with malignant breast tissue.
38. The system of claim 35, further comprising a display screen
configured to render one or more images associated with the
malignant portion of the volume of tissue.
39. The system of claim 35, wherein a circumference and/or a radius
of an inner portion of the receptacle is configured to be
modified.
40. The system of claim 35, wherein the light source and the light
detector are disposed between an inner surface and an outer surface
of the receptacle.
Description
[0001] This application is a divisional of and claims the benefit
of priority to co-owned U.S. patent application Ser. No. 14/984,717
of the same title filed Dec. 30, 2015 issuing as U.S. Pat. No.
10,357,162 on Jul. 23, 2019, the foregoing being incorporated
herein by reference in its entirety.
FIELD OF THE INVENTION
[0002] This invention relates to detection of subcutaneous cellular
mass utilizing optics and imaging techniques. More particularly,
this invention is related to detecting (a) abnormal growth of
tissues inside the body, (b) their types, (c) their dimensions, and
(d) their location from outside the body (through non-invasive
contact or non-contact with the body). More specifically, this
invention is related to the means to detect abnormalities of tissue
growth inside the body, their types, dimensions, and location from
outside, more particularly the early diagnosis of the cancer,
especially breast cancer. This invention also relates to a medical
device that emits electromagnetic waves of varying wavelengths and
detects waves returned to the device.
BACKGROUND OF THE INVENTION
[0003] Breast cancer is an uncontrolled growth of cells in breast
tissue caused by a genetic abnormality, resulting in malignant
tumors, typically originating from the inner lining of milk ducts,
glands that supply the ducts with milk, or less commonly, from the
fatty and fibrous tissues..sup.1 Nearly all cases of breast cancer
occur in women..sup.2 Statistically, breast cancer accounts for the
most deaths caused by all other cancers except lung cancer, and
about one in eight women who reach the age of eighty will have
developed breast cancer..sup.i Older women are more at risk of
having breast cancer.
[0004] In early stages (i.e., stage 0 and stage 1A) of breast
cancer, cancer cells stay in the breast. As the cancer progresses,
cancer cells eventually spread into the underarm lymph nodes. Lymph
nodes are small organs of the immune system located throughout the
body, including the armpit, which are linked by vessels. If cancer
cells spread into the lymph nodes, they have access to other parts
of the body.
[0005] Early detection is paramount to preventing breast cancer
from progressing to dangerous stages. If detected in its early
stages, it is likely that the tumor is small and still confined to
the breast and therefore more likely to be treated successfully.
However, if the tumor is not detected until it has grown large and
spread into the lymphatic system, chances of survival are greatly
decreased. Therefore, it is important that women be screened often
to catch the cancer early and increase their chances of survival.
Unfortunately, there is no device available that a woman may use to
regularly screen herself for breast cancer at home. Currently,
alternative detection and screening methods exist, including
physical examination, genetic screening, mammography,
ultrasound-based screening, and breast magnetic resonance imaging
(MM), among others. A clinical or self-performed breast examination
involves feeling the breast for abnormalities. It is not an
effective preventive method because finding a lump likely indicates
that the tumor has already been growing for years. There is no
evidence that routine examination reduces morality rates, and it is
no longer a recommended screening method.
[0006] Genetics play a minor role in determining risk factors.
Genetic testing focused on inherited BRCA1 and BRCA2 gene mutations
allow women to assess a risk profile for developing breast cancer
before a certain age. Such genetic screening does not detect the
presence of breast cancer, but it may reveal a person's
susceptibility to develop it. The U.S. Preventive Services Task
Force, composed of primary care and prevention experts, recommends
against routine testing unless family history suggests a higher
risk of BRCA1 or BRCA2 mutations. Having a close relative diagnosed
with breast cancer increases a woman's risk of breast cancer.
However, about eighty-five to ninety percent of breast cancers
occur naturally in women who have no family history of breast
cancer. Only five to ten percent of occurrences are caused by
inherited mutations. Therefore, to detect breast cancer early, it
is important to perform regular testing rather than rely on one's
susceptibility to breast cancer. Moreover, since only a small
percentage of breast cancer occurrences is caused by inheriting
mutations, it is not a method that would be beneficial for the
general public.
[0007] The two leading techniques for breast cancer screening are
mammography (see FIG. 1A) and magnetic resonance imaging (MM).
Mammography is a diagnostic and screening procedure whereby
low-energy X-rays are used to create images, which are then
reviewed by a physician for signs of cancer. The American Cancer
Society recommends that women over the age of forty receive a
screening mammogram every year. Some studies show that the decrease
in rate of breast cancer deaths is due to mammography. However,
there is continued debate about whether this method is less helpful
than it is helpful. For example, one of the drawbacks is that false
positives create long-lasting psychological stress and anxiety,
which can affect the patient's wellness and behavior for many
years. On the other hand, false negatives estimated up to thirty
percent occur, which can lead to missed opportunities for treatment
if regular checking is not done. Mammograms do not work well in
younger women because their breast tissue is denser. Cost can
further be an issue, more so because insurance policies tend not to
cover mammograms for women under forty, even though women in their
teens or twenties are sometimes diagnosed with breast cancer.
Ultimately, it has been shown that death rates over 25 years were
the same among women ages 40 to 59 regardless of whether or not
they underwent regular mammograms. Other drawbacks include
discomfort and limitation in detection accuracy. Patients
undergoing mammograms have their breasts compressed, which can
cause pain or discomfort. Tumors sized smaller than one millimeter
are difficult, if not impossible, to detect. Given the balance of
benefits, drawbacks and costs, overtreatment by mammography is
common. Medical ultrasonography is a supplement to mammography that
uses ultrasound to image breast tissue that is denser or deeper in
from the surface of the skin. While it increases the detection rate
of breast cancer, it also increases the rate of false positives.
Ultimately, even purely ultrasound-based screening may warrant an
invasive biopsy procedure to confirm whether a tumor exists in the
tissue sample removed from the patient's body and determine whether
that tumor is benign (non-cancerous) or active (malignant).
[0008] Breast MM is an alternative to mammography. Breast MM may
also be recommended to accompany mammography in women at high risk
for breast cancer. In MM, magnets and radio waves are used to
create pictures of the breast and surrounding tissue. Its main
benefit over mammography is that it dramatically reduces false
negatives, giving a negative result great certainty in ruling out
the presence of cancer. Breast MRI is more sensitive and able to
detect the presence of cancer cells that are not detectable via
mammograms, including tumors that are too small, tumors within
dense tissue material, and tumors that are clearly benign. However,
it also produces greater false positives and is expensive, costing
thousands of dollars. It requires a specialist to administer the
MRI and interpret the results. It is a time-consuming and invasive
procedure requiring injection of a contrast agent that poses a risk
to patients with a history of renal disease. Patients with metallic
substances inside them, such as a pacemaker or breast
reconstruction material, also may not use MM. Thus, MRI is reserved
for certain types of patients, such as those with family history of
breast cancer, those who are at genetic risk, or those who have
dense or abnormal breast tissue (e.g., implants, scars,
augmentations).
[0009] Both mammography and breast MRI procedures require a biopsy
(see FIG. 1B) to histopathologically verify the presence of
cancerous tissue, because not all breast tumors are cancerous and
in need of removal. During a biopsy, a physician takes a sample of
tissue from the suspicious area of the breast and tests it for
cancer. Up to seventy-five percent of biopsies performed on tissue
determined to be cancerous by mammogram and MRI have been found to
be benign. Removing tissue from the breast can be a physically and
psychologically challenging procedure. There exists a need for a
screening technique that eliminates the cost and stress of unneeded
biopsies.
[0010] Recently, there have been attempts to screen for breast
cancer without the need for a biopsy. One such method is the use of
computer-aided tomography (CAT scans) for breast cancer imaging. A
dye is introduced intravenously and two-dimensional cross sectional
images of the breast are produced. A computer may then combine
these images to produce detailed pictures. Currently, this
technique is not used for breast cancer screening and is typically
only used for large-scale imaging of the entire body to determine
if the cancer has spread from the breast area. In addition, this
technique is not non-invasive because it requires the injection of
the dye as well as a visit to the physician. Similar to the use of
CAT scans is the use of fluorescent probes and near-infrared
radiation (NIR). To use fluorescent probes, a drug is introduced to
the test subject intravenously that will preferentially absorb into
cancerous cells. It then interacts with the cells in vivo to
produce a dye whose fluorescence may be imaged when exposed to a
particular wavelength of light. While the use of light in the NIR
range has the advantage of being highly sensitive and specific (can
also reach deep tissue), it has the same problems as CAT scans in
that it requires the injection of a drug and cannot be performed
without the aid of a physician.
[0011] NIR can be used in a less-invasive technique that studies
oxygen metabolism and blood volume in tissue. Since tumors grow
more rapidly and require more nutrients than normal tissue, tumors
also require additional blood vessels to supply these nutrients.
Detecting the presence of additional blood volume and changes in
blood oxygenation can thus be indicative of a tumor. Through NIR
imaging, areas of large hemoglobin density (i.e., cancerous tissue)
may be evidenced by areas of shadow when illuminated by NIR light
at certain wavelengths because hemoglobin absorbs light at these
wavelengths. This technology has the advantage of being
non-invasive and capable of use as a home diagnostic device.
However, this technology is limited by the difficulty in
distinguishing between absorption and scattering in tissue, as well
as the need to rely on secondary factors (oxygen metabolism and
blood volume) to determine the presence of a tumor.
[0012] Breast cancer screening remains an important procedure for
women because of breast cancer's implications to their psyche,
their body and their very life. Breast cancer has been known for
thousands of years, and modern medical successes have allayed
confusion from times past and provided ways to potentially save
women's lives. Nevertheless, it can be seen that current methods of
breast cancer screening and diagnostic methods can be stress
inducing, unreliable, bulky, invasive, and costly. Moreover, some
women may also feel a stigma associated with breast cancer, and
going through medical procedures related to breast cancer can make
them feel especially vulnerable to privacy issues.
[0013] Therefore, it would be useful and desirable to have a
portable, non-invasive device that is handheld and with which women
may use to screen themselves for breast cancer without the need to
visit a physician. The present invention provides such a
non-invasive device that is not only capable of producing
high-resolution, three-dimensional images of abnormalities of
breast tissue but it can also detect the type of abnormalities and
their location using multispectral imaging techniques. As the
present invention uses broadband sources and/or multiple coherent
sources, secondary factors such as oxygen metabolism or blood
volume associated with the cancer tissues could also be detected to
provide further verification of the type. Quick delivery of images
and results in the privacy of one's home allows the user to
interpret the results and decide whether to invest further time and
energy by visiting a physician.
SUMMARY OF INVENTION
[0014] The present invention aims to overcome problems associated
with current technologies by providing a device that is friendly to
users and makes screening and diagnosis of breast cancer more
sensitive, more rapid, non-invasive, and less costly, allowing for
early detection of emerging tumors through routine
self-examination.
[0015] The following presents a summary of the invention and a
basic understanding of some of the aspects of the invention. It is
not intended to limit the scope of the invention or provide
critical elements of the invention. Its sole purpose is to present
some of the features of the invention in a simplified form as a
prologue to the more detailed description presented later.
[0016] It is an object of this invention to allow breast cancer
screening and diagnosis to be non-invasive.
[0017] It is an object of this invention to encourage routine
breast cancer screening that is self-operable, more private, easier
to use, yet cost-effective.
[0018] It is an object of this invention to raise the accuracy of
diagnosis and reduce the rate of false positives and false
negatives.
[0019] It is an object of this invention to incorporate several
cancer-detecting techniques to achieve high accuracy.
[0020] In one aspect of the present disclosure, a method for
detection of breast cancer using a user device is disclosed. In one
embodiment, the method includes:
[0021] emitting an optical signal via a light source of the user
device; enabling interaction between the emitted optical signal and
one or more portions of the tissue, the interaction producing one
or more returning optical signals; detecting the one or more
returning optical signals via one or more light detectors of the
user device; comparing an optical characteristic associated with
each of the one or more returning optical signals with one or more
optical characteristics corresponding to an interaction with breast
tumor cells; based on a determination that a correlation exists
between the compared optical characteristic and the one or more
optical characteristics corresponding to an interaction with breast
tumor cells, determining a position of at least one of the one or
more portions of the tissue.
[0022] In another aspect of the present disclosure, a user
apparatus for detection of breast tumor is disclosed. In one
embodiment, the user apparatus includes: a processor apparatus
configured to cause the user apparatus to: emit an optical signal
toward a tissue of a user via a light emitter; cause interaction
between the emitted optical signal and one or more portions of the
tissue, the interaction producing one or more returning optical
signals; detect the one or more returning optical signals via a
light detector; determine a location of a malignant portion of the
tissue based on a correlation between (i) an optical parameter
associated with each of the one or more returning optical signals
and (ii) one or more optical characteristics corresponding to
breast tumor cells.
[0023] In another aspect of the present disclosure, a system for
detection of breast cancer is disclosed. In one embodiment, the
system includes: a processor apparatus configured to cause a user
device to: produce, via a light source, an optical signal emitted
toward a volume of tissue of a user; detect, via a light detector,
the one or more returning optical signals from the volume of tissue
of the user subsequent to an interaction with the produced optical
signal with the volume of tissue of the user; determine a position
of a malignant portion of the volume of tissue based on a
comparison between (i) an optical parameter associated with at
least some of the one or more returning optical signals and (ii)
one or more optical characteristics correlated with an interaction
of an optical signal with malignant breast.
BRIEF DESCRIPTION OF DRAWINGS
[0024] For a better understanding of the aforementioned aspects of
the invention and additional aspects and embodiments thereof,
reference should be made to the Detailed Description, below, in
which reference numerals refer to corresponding parts throughout
the figures under Drawings.
[0025] FIG. 1A shows a basic overview of the prior art of
mammography.
[0026] FIG. 1B shows a basic overview of the prior art of biopsy on
a breast tissue.
[0027] FIG. 2 shows a block diagram illustrating the basic
operational parts of the present invention.
[0028] FIG. 3 shows a sample graph of an example of an absorption
spectrum.
[0029] FIGS. 4A-4G show various arrangements of light sources that
may be implemented in accordance to the present invention.
[0030] FIG. 5A shows a schematic of basic parts of a light
detector.
[0031] FIGS. 5B and 5C show various arrangements of detectors that
may be implemented in accordance to the present invention
[0032] FIGS. 6A-6E show various arrangements of sources and
detectors that may be implemented in accordance to the present
invention.
[0033] FIGS. 7A and 7B show schematics of a preferred "non-contact"
embodiment in an angled view.
[0034] FIG. 8A shows a schematic of the preferred "non-contact"
embodiment in a cross-sectional view.
[0035] FIGS. 8B and 8C show schematics of a source panel and a
detector panel, respectively, used in the preferred "non-contact"
embodiment.
[0036] FIG. 9 shows a schematic of another preferred "non-contact"
embodiment in a cross-sectional view.
[0037] FIG. 10 shows a schematic of another preferred "non-contact"
embodiment in a cross-sectional view.
[0038] FIG. 11A shows a schematic of a preferred "flip-open
non-contact" embodiment in a top view.
[0039] FIGS. 11B and 11C show schematics of the preferred
"flip-open non-contact" embodiment in a front view.
[0040] FIG. 12A shows a schematic of another preferred "flip-open
non-contact" embodiment in a top view.
[0041] FIGS. 12B and 12C show schematics of the another preferred
"flip-open non-contact" embodiment in a front view.
[0042] FIGS. 13A and 13B show schematics of a preferred embodiment
with a self-adjusting cavity.
[0043] FIG. 14A shows a schematic of the preferred embodiment with
a self-adjusting cavity from a cross-sectional view.
[0044] FIG. 14B shows schematics of parts related to the preferred
embodiment with a self-adjusting cavity.
[0045] FIGS. 15A and 15B show schematics of a preferred "flexible
contact" embodiment in a front view and an angled view,
respectively.
[0046] FIGS. 16A and 16B show schematics of preferred "flexible
contact" embodiments in a cross-sectional view.
[0047] FIG. 16C shows a schematic of a part of a preferred
"flexible contact" embodiment.
[0048] FIG. 17A shows a schematic of a preferred "flexible contact"
embodiment in a cross-sectional view after making contact with a
breast.
[0049] FIGS. 17B and 17C show schematics of a source panel and a
detector panel, respectively, used in the preferred "flexible
contact" embodiment.
[0050] FIG. 18 shows a schematic of another preferred "flexible
contact" embodiment in a cross-sectional view after making contact
with a breast.
[0051] FIG. 19 shows a schematic of another preferred "flexible
contact" embodiment in a cross-sectional view after making contact
with a breast.
[0052] FIGS. 20A-20E show schematics of various forms of a
supplementary layer used to improve functionalities of the present
invention.
[0053] FIGS. 21-27 show a whole view of schematics of operational
parts implemented in preferred embodiments of the present
invention.
[0054] FIG. 28 shows a schematic of an optical-fiber cable used in
the present invention.
[0055] FIGS. 29A-29C show schematics of the present invention
implemented in various example devices.
DETAILED DESCRIPTION OF THE INVENTION
[0056] Reference numerals refer to corresponding parts labeled
throughout the figures. The embodiments described herein pertain to
a device that detects and images subcutaneous cellular mass through
optical techniques. The embodiments pertain to methods and
apparatuses for screening and diagnosis of breast cancer.
[0057] As used herein, the term "area of interest" and "area of
concern" refer to parts of bodily tissue where cancer cells are
suspected or known to be. For example, a woman (or man) may undergo
mammography on her breasts where she felt a lump. The general area
where the lump was would be an area of concern because it is
suspected that cancer cells may be developing in the lump. In
particular, a "tumor" is an abnormal growth of cells, especially
malignant neoplasms that invade nearby cells (cancer).
[0058] As used herein, the term "biomass" refers to a total mass or
volume of organic matter, typically from the human body. It could
be an entire organ or portion thereof, a section of skin, lymph or
blood vessels present throughout the body, and/or a collection of
cells, ex vivo or in vivo. In the present invention, discussion of
"biomass" is aimed primarily at the breast as well as internal and
external components of the breast up to the chest cavity.
[0059] As used herein, the terms "light," "radiation,"
"electromagnetic wave" and "electromagnetic waves" are
interchangeable, unless specified. "Broadband" light refers to
light carrying waves of varying wavelengths, typically a range of
wavelengths (or a band). Broadband light is generated by a
broadband source, which may emit multiple ranges of wavelengths to
selectively emit multiple groups of wavelengths. On the other hand,
"uniband" or "coherent" light refers to light having one particular
wavelength or a narrow range of wavelengths.
[0060] As used herein, the terms "reflect," "refract," "scatter,"
"diffract" and "fluoresce" refer to the behavior of light waves
upon interacting with another material. "Reflect" refers to a
process in which light and other electromagnetic radiation are cast
back after impinging on a surface. "Total internal reflection"
occurs when light strikes a medium boundary at an angle larger than
a particular critical angle with respect to the normal to the
surface. "Refract" refers to change in direction of electromagnetic
radiation in passing from one medium to another. The optical
density of a medium is the refractive index, an inherent value of
the medium. "Fluoresce" refers to exhibiting fluorescence, which is
refers to emission of electromagnetic radiation stimulated in a
substance by the absorption of incident radiation. "Diffract"
refers to exhibiting diffraction, which refers to a deviation in
the direction of a wave at the edge of an obstacle in its path.
"Scatter" and "diffract" are interchangeable.
[0061] As used herein, the term "panel" associated with light
sources and light detectors refer to a continuous and generally
transparent surface that emits or receives light. Multiple light
source and light detector units are housed under a panel. This is
distinguishable from a mere collection or array of sources or
detectors. An array is an arrangement of sources or detectors, but
each source or detector is discretely placed, not connected to one
another or housed under one transparent pane.
[0062] The terminology used in the descriptions of the embodiments
herein is for the purpose of describing particular embodiments only
and is not intended to limit the claims. The singular articles "a,"
"an" and "the" are intended to include the plural forms as well,
unless the context clearly indicates otherwise. It will also be
understood that the term "and/or" refers to and encompasses any and
all possible combinations of one or more of the associated listed
terms. Similarly, the conjunction "or" is not necessarily mutually
exclusive.
[0063] References will now be made in detail to embodiments,
accompanied by numerals that correspond to appropriate parts of the
figures. Examples will be provided to illustrate the various ways
the present invention may be utilized. Specific details will be set
forth to provide a thorough understanding of the present invention.
However, it will be apparent to those with ordinary skill in the
art that the present embodiments may be practiced without these
specific details. In other instances, known methods, procedures and
components have not been described in detail to avoid unnecessarily
obscuring aspects of the embodiments.
[0064] [Theory: reflect light off tumor tissue, increase accuracy
with secondary factors--water, Hg, PE, PC)] When a beam of light
interacts with a material, e.g., a tumor, part of it is
transmitted, part it is reflected, and part of it is diffracted
(scattered). Various scattering types result based on the size of
the particle and the wavelength of the incident radiation, though
it occurs at all wavelengths of the electromagnetic spectrum. The
equation to determine the scattering type is described by:
.alpha.=.pi.D.sub.p/.lamda., where .pi.D.sub.p is the diameter of
the particle, and A is the wavelength of the incident radiation.
The value of a determines the domain of the scattering type. If
a<<1, it is Rayleigh scattering, in which the particle is
very small compared to the wavelength. If .alpha..apprxeq.1, it is
Mie scattering, in which the particle is about the same size as the
wavelength. If .alpha.>>1, it is geometric scattering, in
which the particle is much larger compared to the wavelength.
Particles with sizes very small (r<.lamda./10) compared to the
wavelength of incident radiation, scatter uniformly into both the
forward and backward direction. Over 99% of the scattered radiation
has the same frequency as the incident beam. Thus, incident light
that has diffracted is identifiable by its wavelength. Mie and
Rayleigh scattering types exhibit this type of behavior. A small
portion of the scattered radiation has frequencies different from
that of the incident beam: Raman and Brillouin scattering have
forms of inelastic scattering. Fluorescence of light occurs where a
substance that has absorbed light or other electromagnetic
radiation and emits light, which is lower energy than the absorbed
radiation, unless the absorbed electromagnetic radiation is
sufficiently intense. The two-photon absorption process helps
fluorescing light emit radiation having higher energy after
absorption. In the present invention, single-photon absorptions
and/or two-photon absorptions can be used to further verify the
type and dimensions of the cancer tissue. According to this
invention, two-photon absorptions help detect the cancer cells that
exist deeper in the body and identify the size and type of
tissues.
[0065] Reflection or refraction of light may occur whenever light
travels from a medium of a given refractive index into a medium
with a different refractive index. Total internal reflection occurs
when light strikes a medium boundary at an angle larger than a
particular critical angle with respect to the normal to the
surface. If the refractive index is lower on the other side of the
boundary, no light can pass through and all of the light is
reflected. The critical angle is the angle of incidence above which
the total internal reflection occurs. Diffuse reflectance may occur
at boundaries of different substances or particles, where light is
partially reflected (few percent intensity) while passing the
boundary. Refraction of light is described by Snell's law: The
angle of incidence .theta..sub.1 is related to the angle of
refraction .theta..sub.2 in another medium by sin .theta..sub.1/sin
.theta..sub.2=n.sub.2/n.sub.1, where n is the refractive index.
[0066] Photon propagation in tissue can be further described by
five variables: 3 spatial coordinates to describe the position
(Cartesian coordinates) and 2 directional angles to describe the
direction of travel (spherical coordinates). The relationship
between penetration depth of light and its wavelength can be
described by: Effective penetration depth=1/.mu.(eff);
.mu.(eff)=effective attenuation
coefficient=[3.mu.(a).times.(.mu.t(a)+.mu.(s'))].sup.0.5; where
.mu.(s')=attenuation coefficient=.mu.(s)(1-g); .mu.(a)=absorption
coefficient; .mu.(s)=scattering coefficient; and g=anisotropic
properties. The latter optical properties are measurable or known
values for a type of tissue material.
[0067] FIG. 1A illustrates a basic overview of the prior art of
mammography. It is a technique that involves compressing a breast
102 and utilizing X-rays to create images for review. Breast 102 is
placed between a compression paddle 104 and a film table 106.
Compression paddle 104 moves to squeeze breast tissue 102,
resulting in discomfort and pain to the patient. Compressed breast
108 is then imaged by an X-ray tube 110. The images are reviewed by
a physician to locate any suspicious areas for further examination
through biopsy. FIG. 1B illustrates basic methods of biopsy
procedures on an area of concern 112. The procedure may involve
removing a tissue 114 by using a needle 116 or excising it in a
more surgical manner. Both methods involve an invasive procedure
that removes part of the breast tissue for histological analysis,
which, together with the previous procedure, can place physical and
emotional stress on the patient.
[0068] FIG. 2 is a block diagram illustrating the overarching
concept of the present invention. At time t.sub.0, a light source
200 emits light 202 of a particular wavelength ("uniband") or
varying wavelengths ("broadband") into a breast tissue 204. In some
embodiments, each source 200 is lined up in a two-dimensional
fashion to create an array of sources (see below). Each source 200
may emit a certain wavelength. In some other embodiments, sources
emitting the same wavelength may be grouped into larger panels. In
yet other embodiments, each source 200 may emit a range of
wavelengths. A source driver 206 drives source 200 and selects the
pulse duration to be operated. Source 200 can be operated in
continuous wave (CW) or pulse operation based on the necessities,
and it converts electric signals to optical signals. A controller
208 receives instructions to provide signals to a source driver
136, which operates a specific source. Alternatively, controller
208 also receives instructions to operate the sources having
specific wavelengths and/or specific ranges of wavelengths in
either pulse or CW operation. According to this invention,
alternatively, controller 208 can be operated and are instructed by
one or more circuit blocks (not shown here) to operate desired
source, desired wavelength(s), desired pulse-width/CW, desired
intensity, or a combination thereof.
[0069] Light 210 returns as a reflection, or scatters and comes
back as diffracted, refracted, or scattered light. At time t.sub.1,
a detector 212 receives returned light 210 of a certain wavelength.
Detector 212 converts light 210 into electrical signals, which are
sent to a signal amplifier 214. A digitizer 216 turns the amplified
signal into digital form. A processing element ("processor") 218
performs calculations that can create three-dimensional images from
two-dimensional images. Processor 218 produces other important
data. For instance, it determines the location of areas of concern
by deriving times of flight t.sub.1-t.sub.0 and the size of areas
of concern by comparing images from light of different wavelengths.
Although some absorption of emitted light 202 occurs, if an object
has a size smaller than the wavelength of light hitting it,
diffraction and scattering of the light occurs. On the other hand,
if an object has a size larger than the wavelength of light, the
object reflects the light. Thus, processor 218 may determine the
size of potential tumors by collecting images based on light 202 of
varying wavelengths. Processor 218 then sends relevant information
to a display screen 220 for a user to read.
[0070] According to this preferred embodiment, processor 218
operates the transmission elements and the receiving elements (not
shown here specifically), and processes the receiving signals based
on a build-up algorithm, described later. The transmission elements
(not shown here specifically) comprise controller 208, driver 206,
and source 200. Processor 218 instructs the transmission elements
and receiving elements, based on its determination of how to
operate the source and which part of receiving elements should be
processed.
[0071] By way of example and without any limitation, in FIG. 2, the
source can be operated in various ways using components having the
functionality to select the source, wavelength, pulse/CW, and
source intensity, and in various ways processor 218 can operate the
transmitter elements and receiving elements, as instructed by
software, either embedded into processing unit 218, and/or
separately operated by a computing unit with or without display
element 220 externally interfaced with processor 218.
[0072] According to this invention, alternatively, the components
as shown in FIG. 2 may be grouped in different locations. The
dotted lines above the block diagram indicate how the components
may be grouped together. In some embodiments (Embodiment A), light
sources 200 and detectors 212 are placed together in a handheld
device separate from the module containing processor 218 along with
the other components illustrated. The handheld device is henceforth
referred to as the "user end"; the latter module is henceforth
referred to as the "processor end". During operation, the user
directly manipulates the handheld "user end" device over her
breast, emitting light 202 and detecting returning light 210. Light
210 that returns to the user end is sent to the processor end
(containing processor 218) through electrical, optical, or wireless
channels (see FIGS. 21-27). The transmitted signals are then
amplified, processed, and may be displayed on screen 220.
[0073] According to this invention, in some other embodiments
(Embodiment B), light sources 200, detectors 212, and processor 218
are in the processor end. Initial emission and later collection of
light are both performed at the processor end. Light 202 emitted
from sources 200 and light 210 returned to the detectors 212
propagate through an optical-fiber cable. At the other end of the
optical cable is a handheld device on the user end, which the user
places, moves, or otherwise manipulates over breast tissue 204.
This device delivers light 202 emitted and carried via optical
means from sources 200, and then collects and focuses returned
light 210 for transmission back through the optical cable to
detectors 212. Electrical or wireless means are not used in these
embodiments because only optical signals travel between the user
end and the processor end.
[0074] In yet other embodiments (Embodiment C), light sources 200,
detectors 212, and processor 218 are in one device: the user end.
All light generation, data gathering, processing, and imaging are
done within the handheld device. End result of operation, such as
images and other data, are transferred via electrical, optical, or
wireless means to display screen 220 or another device, such as a
mobile device or a monitor of a computer. Other means of
implementation and descriptions of accompanying figures are
disclosed below to reveal a closer look at the arrangements of
sources 200 and detectors 212.
[0075] A diffraction pattern, i.e., an interference pattern that
propagates uniformly when a wave or a series of waves undergoes
diffraction, results if an obstacle has a size smaller than the
wavelength of optical wave encountering the object. The pattern
provides information about the frequency of the wave and the
structure of the material causing the diffraction. An
interferometer can be used to detect the nature of the diffraction
pattern.
[0076] Functions of above-described embodiments of the handheld
device are driven by software programs. There are several main
functions. One function of the device can perform a rough spatial
scan of the breast tissue to locate possible areas of concern. The
rough spatial scan is performed with variation of intensity (thus
varying the depth) per unit area per unit time. The scan spatially
covers the breast tissue by emitting broadband light, coherent, or
incoherent sources, and then collecting any returning light. If
light returns, the reflected light has varying patterns--direct
reflection, diffraction, fluorescence--based on the size (early
stage or later stage), characteristic of the cells (mere
calcification, hard-shelled tumor or soft-shelled tumor) the
emitted light struck, and the nature of the emitted light. The scan
also covers the tissue depth-wise by varying the intensity and/or
wavelength of the emitted light. The scan detects tumor-like
substances by matching the returning light with known diffraction
patterns or spectral profiles of cancerous lesions. It can then
continue with a detailed scan and iterations with varying optical
parameters in the areas of concern for further analysis and
obtaining results, which may include a high-resolution scan,
determination of depth and location, construction of a
three-dimensional image, and identification of the type of the
tissue substance (normal, healthy tissue vs. harmless calcification
vs. early-stage tumor). Optical parameters include wavelength,
energy fluence rate (flux over time), pulse rate, absorption
coefficient, scattering coefficient, refractive index, scattering
phase function. Light propagation in scattering and absorbing media
can be defined with respect to radiative transfer.
[0077] According to one-dimensional transport theory, light
propagation in scattering and absorbing media can be defined by
integro-differential equation of radiative transfer, assuming 1)
optical properties can be measured, 2) light propagation is
restricted to +x or -x directions, and 3) the tissue light
interacts with is homogenous and isotropic. Optical properties
under this model include: .mu..sub.a1=absorption coefficient for 1D
geometry, [m.sup.-1]; .mu..sub.s1=scattering coefficient for 1D
geometry, [m.sup.-1]; .sigma.=backscattering coefficient where
.mu..sub.s1p(+,-)=.mu..sub.s1p(-,+),[m.sup.-1]; p({circumflex over
(x)},{circumflex over (x)}')=scattering phase function where
{circumflex over (x)} and {circumflex over (x)}' are directional
unit vectors; F+(x)=photon flux in +x direction, [Wm.sup.-2];
F-(x)=photon flux in -x direction, [Wm.sup.-2]; E=incident (laser)
irradiance, [Wm.sup.-2]. Accordingly, .mu..sub.a1 dx=probability
that a photon is absorbed when traversing infinitesimal distance
dx; .mu..sub.s1 dx=probability that a photon is scattered into
either +x or -x direction when traversing infinitesimal distance
dx; p({circumflex over (x)},{circumflex over (x)}').mu..sub.s1
dx=probability that a photon is scattered from the direction of
propagation {circumflex over (x)}' into direction {circumflex over
(x)} when traversing infinitesimal distance dx. The following
equations hold true under this one-dimensional transport
theory.
[0078] 1D transport equations (1) and (2):
F + ( x + dx ) - F + ( x ) = - F + ( x ) .mu. a 1 dx - F + ( x )
.mu. s 1 dx + F + ( + , + ) .mu. s 1 dx + F - ( x ) p ( + , - )
.mu. s 1 dx ( 1 ) dF + ( x ) dx = - F + ( x ) ( .mu. a 1 + .mu. s 1
) + F + ( x ) .mu. s 1 p ( + , + ) + F - ( x ) .mu. s 1 p ( + , - )
( 2 ) ##EQU00001##
[0079] Backscattering coefficient (3):
.sigma.=.mu..sub.s1p(-,+)=.mu..sub.s1p(+,-) (3)
[0080] Differential photon flux in +x and -x directions, equations
(4-1) and (4-2):
dF + ( x ) dx = - ( .mu. a 1 + .sigma. ) F + ( x ) + .sigma. F - (
x ) ( 4 - 1 ) - dF - ( x ) dx = - ( .mu. a 1 + .sigma. ) F - ( x )
+ .sigma. F + ( x ) ( 4 - 2 ) ##EQU00002##
[0081] 1-D fluence equations (5) and (6), where
m=.mu..sub.a1+.sigma.)/.sigma..sub.b and b= {square root over
(m.sup.2-1)}:
F + ( x ) = E m sinh [ b .sigma. ( D - x ) + b cosh b .sigma. ( D -
x ) ] m sinh ( b .sigma. D ) + b cosh ( b .sigma. D ) ( 5 ) F - ( x
) = E sinh [ b .sigma. ( D - x ) ] m sinh ( b .sigma. D ) + b cosh
( b .sigma. D ) ( 6 ) ##EQU00003##
[0082] Energy fluence rate can be related to depth or distance by
equation (7), where L=radiance, [W/m.sup.2*sr]; p=phase of
scattering function; S=source of power generated at r in direction
of s':
d L ( r , s ^ ) ds = - .mu. a L ( r , s ^ ) - .mu. s L ( r , s ^ )
+ .mu. s .intg. 4 .pi. p ( s , s ^ ' ) L ( r , s ^ ' ) d .omega. '
+ S ( r , s ^ ' ) ( 7 ) ##EQU00004##
[0083] Another function of the invention is to determine the
wavelengths of the light before it is emitted and whether different
wavelengths of light are emitted simultaneously. Individual
(uniband) wavelengths may be emitted, scanning the entirety of the
target breast tissue one wavelength at a time. With time and effort
expended up front, this would narrow down the wavelengths that
respond to any potential areas of concern. On the other hand, a
range or broadband wavelengths may be emitted. Depending on the
range of wavelengths, this method would provide a rough analysis in
which a larger scope of potential areas of concern would be
collected.
[0084] FIG. 3 illustrates an example of an absorption spectrum 300
of light by an arbitrary mass or volume of tissue. As the
wavelength of light changes, so does the level of absorption by a
material. Shown are two arbitrary wavelengths, .lamda..sub.1 and
.lamda..sub.2. At .lamda..sub.1, absorption of electromagnetic wave
having wavelength .lamda..sub.1 increases. This is an effective
wavelength to target with a light source because some absorption is
desired to distinguish between emitted light and reflected light,
which would have a lower relative intensity than that of emitted
light. At .lamda..sub.2, absorption of electromagnetic wave having
wavelength .lamda..sub.2 is high. It may not produce useful images
if most of the light is absorbed and not returned to a detector.
Based on absorption spectra of particular materials of interest,
such as those of breast tumor tissue, water, hemoglobin, lipids
abundant in breast tumors (such as phosphatidylethanolamine, "PE"
and phosphatidylcholine, "PC"), the light sources are configured in
a way that emits a range encompassing relevant wavelengths that
would produce useful data. In some wavelengths, either lower than
.lamda..sub.1 and/or longer than .lamda..sub.2, the specific
material(s) does not have an absorption and is transparent to those
wavelengths.
[0085] Light sources may be light-emitting diodes, lasers, or
broadband sources. LEDs would have a broader wavelength spectrum,
but they are less ideal for generating high-resolution,
wavelength-specific data. Lasers offer greater precision and
specificity of wavelengths, but their power output should be
carefully controlled. Specifically, the full width at half maximum
of the spectral width of the LED (.lamda..sub.1) would generally be
greater than that of a laser source (.lamda..sub.2). Broadband
sources may be better served by LEDs, while uniband sources may be
better served by lasers. Alternatively, according to this
invention, broadband sources having broader spectrum than the LEDs,
can also be used as source 200. Practical configurations of LEDs,
broadband sources, and/or lasers as light sources will be apparent
to those having ordinary skill in the art.
[0086] FIGS. 4A-4E and 4G illustrate arrays of light sources
(emitters) in various configurations, in accordance to the present
invention, wherein like parts are indicated by like reference
numerals as used previously, so that repeated explanation is
omitted here. FIG. 4A shows an embodiment wherein an array 400 of
light sources has k.times.n array, representing k numbers of light
source in x-direction and n numbers of array in y-direction, where
k and n are positive integers. In the embodiment illustrated, each
source in array 400, produces light of a certain wavelength; every
source in array 400 is a unique source that emits light of relevant
wavelengths. For instance, the first source 402 produces light of
wavelength .lamda..sub.1, an adjacent source 404 produces
.lamda..sub.2, a source 406 adjacent to that produces .lamda..sub.3
and so on. No two sources emit the same wavelength in this
configuration. The source emitting light of wavelength
.lamda..sub.kn 408 is the "knth" source that produces a different
wavelength. Alternatively, according to this invention, sources
having more than one wavelength can be used in the array
arrangement (not shown here).
[0087] According to this invention, in some other embodiments,
shown in FIG. 4B, sources 402 that emit light having a certain
wavelength are grouped together in panels 410. Multiple light
sources with the same wavelength are employed to increase the
resolution of data acquired from reflected or diffracted inbound
light. Each panel 410 produces light waves of a unique wavelength,
and the panels 410 are arranged in an array of k panels by n
panels. Each panel 410 need not necessarily contain the same number
of sources 402. There may be panels that contain a fewer or greater
number of sources 402, depending on the characteristics and purpose
of a particular wavelength. For example, panel 412 has two sources,
and panel 414 has five sources.
[0088] According to this invention, in yet other embodiments, shown
in FIG. 4C, alternatively, light sources are broadband sources,
which carry multiple signals--that is, emit a range of wavelengths.
The ranges of wavelengths of emitted light differ from each other
source, and they may overlap. For instance, a source 416 may emit
light of wavelengths .lamda..sub.a to .lamda..sub.x, where a and x
are arbitrary wavelengths. Another source 418 may emit
.lamda..sub.x+1 to .lamda..sub.y, where x and y an arbitrary
wavelengths, y being greater than x+1. Another source 420 may emit
.lamda..sub.a +n to .lamda..sub.x+n, where a +n is between a and x,
and x+n is between x+1 and y.
[0089] According to this invention, in other embodiments,
alternatively shown in FIG. 4D, each source 422 may produce an
entire range of desired wavelengths. An array 400 of light sources
is shown in FIG. 4D wherein each source 422 produces light of
wavelengths .DELTA..sub..alpha. to .lamda..sub..OMEGA., where
.alpha. is the smallest relevant wavelength desired, and .OMEGA. is
the highest relevant wavelength desired. Such a source 422 may not
emit all wavelengths between .DELTA..sub..alpha. and
.lamda..sub..OMEGA., only the relevant ones within that range.
Broadband sources 424 may be grouped into panels 426, as shown in
FIG. 4E. Similar to the arrangement in FIG. 4B, each panel 426 has
sources 424 emitting light of the same range of wavelengths. The
number of sources 424 may differ for each panel. There may be
panels 428, 430 that contain a fewer or greater number of sources,
depending on the characteristics and purpose of a range of
particular wavelengths.
[0090] FIG. 4F is an illustration of a light source with a filter
432 that allows certain wavelengths to pass through while blocking
other wavelengths in the preferred embodiment, according to this
invention, wherein like parts are indicated by like reference
numerals as used previously, so that repeated explanation is
omitted here. Here, a broadband source 434 generating light 436 of
multiple wavelengths .lamda..sub.1 through .lamda..sub.5 exits
through filter 432. Filter 432 has openings that permit light of
wavelengths .lamda..sub.1, .lamda..sub.2, .lamda..sub.3,
.lamda..sub.4, and .lamda..sub.5 to pass through. The result is
effectively five light sources that each emits light that is no
longer the original light generated by the broadband source. Its
utility is illustrated in FIG. 4G, where light sources 434 are
grouped together in panels. The number of sources may differ for
each panel. There may be panels that contain a fewer or greater
number of sources. Each panel comprises an underlying broadband
source that produces light waves of multiple wavelengths. For
example, underneath upper-left panel 436 is a broadband source that
emits light of wavelengths .lamda..sub.a through .lamda..sub.x, of
which four distinct wavelengths .lamda..sub.a, .lamda..sub.b,
.lamda..sub.c, and .lamda..sub.x are relevant and of interest. By
placing filter 432 over the source panel, one source is simply
divided into multiple light sources that effectively function like
the individual sources in FIG. 4A.
[0091] FIG. 5A illustrates the major components of a light detector
500 that registers light of particular wavelength(s) in a preferred
embodiment, according to this invention, wherein like parts are
indicated by like reference numerals as used previously, so that
repeated explanation is omitted here. Each base detector component
502 is identical in that it detects the presence of light. To
detect light of a particular wavelength or wavelengths, a filter
504 installed over the detector varies among each detector 500.
Filter 504 blocks out other wavelengths, letting only particular
wavelength(s) through. For example, if filter 504 is designed to
allow only waves having wavelengths .lamda..sub.1 and
.lamda..sub.3, light having other wavelengths, such as
.lamda..sub.2, are blocked. Thus, depending on the function of the
filter, detector 500 becomes able to detect only desired
wavelengths.
[0092] FIG. 5B shows a preferred embodiment of an array 506 of such
detectors, the array having width k and length n, in accordance to
this invention, wherein like parts are indicated by like reference
numerals as used previously, so that repeated explanation is
omitted here. Each detector 508 can only see and detect the
presence of light of a certain wavelength: .lamda..sub.1,
.lamda..sub.2, .lamda..sub.3, etc. A detector that detects light of
wavelength .lamda..sub.kn 510 is the "knth" detector that registers
that wavelength. If light of a particular wavelength .lamda..sub.x
reaches array 506 of detectors, only one detector will recognize
it.
[0093] In another preferred embodiment according to this invention,
alternatively, detectors 508 that see light of a certain wavelength
are grouped together in panels 512, shown in FIG. 5C. Multiple
detectors 508 are employed to detect the same wavelength increases
the resolution of data acquired by reflected or diffracted light.
Each panel 512 detects light of a particular wavelength, and the
panels are arranged in an array 514 of k panels by n panels. In
some embodiments, however, a filter is unnecessary for a base
detector component to detect a particular wavelength; such a
detector inherently has the capability to detect a unique
wavelength or a narrow range of wavelengths.
[0094] In yet other embodiments, rather than arranging light
sources and detectors separately from each other, the sources and
detectors can be placed together, as shown in FIGS. 6A-6E. In FIG.
6A, sources 600 that emit light of a certain wavelength and
detectors 602 that detect light of a certain wavelength alternate
on a source-detector array 604 of width 2k and length 2n.
[0095] According to this invention, in another preferred embodiment
shown in FIG. 6B, panels of multiple sources and detectors, rather
than individuals, alternate in a source-detector-panel array 606. A
panel comprising sources 608 emitting light of wavelength
.lamda..sub.1 is adjacent to a panel of detectors 610 that detect
only .lamda..sub.1. Other panels emitting and detecting light of
arbitrary wavelength .lamda..sub.x are arranged similarly.
[0096] In another preferred embodiment shown in FIG. 6C, broadband
sources and specific detectors are placed in alternating fashion on
an array 612 of width 2k and length 2n. Similar to the arrays
illustrated in FIGS. 4C-4E, broadband source 614 here may be
capable of emitting a narrow range, a wide range, or any range of
relevant wavelengths. Each detector 616 or group thereof, however,
registers a particular wavelength. One having ordinary skill in the
art is able to create further variations in arrangements of light
sources and detectors.
[0097] Other arrangements are possible in other embodiments. For
instance, FIG. 6D illustrates sources 618 and detectors 620 of
circular shape positioned in a space-efficient manner. FIG. 6E
illustrates circular sources 618 and circular detectors 620 grouped
in various combinations within panels 622. Similar to the
previously described embodiments, sources 618 may be capable of
emitting a narrow range, a wide range, or a range of relevant
wavelengths. Each detector 620 or group thereof detects a
particular wavelength. Other possible arrangements, shapes, and
configurations (not shown here) will be apparent based on the
aforementioned disclosures.
[0098] The various arrangements of the elements of the present
invention manifested in a device will now be described in further
detail. To emit light and detect reflected or diffracted light,
light sources and detectors must be arranged in a way to emit
appropriate wavelengths of light toward the user's breast tissue
and detect light that returns from the user's breast tissue. The
device can take numerous forms to provide such functions. In some
embodiments, one general shape of the device could be a hemisphere
with a hollow interior cavity. In other embodiments, it could be a
curved surface for making direct contact with the breast tissue. In
yet other embodiments, it could be a more compact device that can
flip open and engage panels of sources and detectors. Other
arrangements, features, structural dimensions, shapes, materials
used, etc., allowing detectors to receive light reflected or
diffracted from the breast tissue will be apparent to those having
ordinary skill in the art.
[0099] FIG. 7A is an illustration showing a schematic diagram of
medical device in an angled view in a preferred embodiment
("non-contact embodiment"), in accordance to this invention that
does not require complete contact with a patient's breast tissue. A
device 700 has a cup 702 in the shape of a hemisphere connected to
a mainframe (not shown here) via a cable 704, which represents a
bundle of optical fibers, an electronic connection, or a wireless
connection. Hemispheric portion 702 is the user end of the
apparatus and is handheld. The mainframe contains a processor that
enables instructions and generates optical signals (light) or
corresponding electrical signals to the handheld device. Outer
shell 706 of the device houses all the components required to
operate the handheld device itself. Outer shell 706 may be composed
of a flexible or semi-rigid (rigid and flexible combination)
polymer, or it may be an inflexible solid encasing. The inside of
the device is a hollow cavity with enough room for a wide range of
breast sizes. The inner cavity has substantial curvature to allow
emission of light from many directions. Inner surface 708 of the
cavity is lined with numerous light sources and detectors or panels
thereof that emit and detect light from panoramic positions,
enabling the device to collect enough data at once to image the
interior of the breast and any areas of interest. Further details
on light paths are given below in discussions of cross-sectional
views.
[0100] Each source 710 and detector 712 is connected to cable 704.
The source-to-cable fibers 714 and detector-to-cable fibers 716 may
be optical or electrical in nature. A few optical fibers are
illustrated in FIG. 7A in dashed lines. Each optical fiber 714, 716
carries optical signals (light), and each electrical wire carries
electrical signals. Light that comes through an optical fiber may
be collected and focused by a lens 718, after which the light
continues to propagate through cable 704 to be processed by the
mainframe. In some embodiments, lens 718 is not needed to focus
light; instead, the light to and from the mainframe directly
travels between a sensor or detector and the mainframe through
optical fibers 714, 716. According to this invention, a focusing
element in the form of a micro-lens can be included on the tips of
fibers 714, 716, on both sides (not shown here) either as a
separate lens array components or as an integrated lens array
formed on the tips of the both ends of each fiber 714, 716.
[0101] Alternatively, in the non-contact embodiment illustrated in
FIG. 7B, data are carried by electrical signals. Like in the
embodiment using optical fibers illustrated in FIG. 7A, the inner
cavity is hollow and has a surface 708 lined with numerous light
sources and detectors or panels thereof that emit and detect light
from panoramic positions, enabling the device to collect enough
data to image the interior of the breast and any areas of interest.
Having electrical wires, detaching a device 720 into separate
components enables compact storage. Electric cable 722 is a ribbon
cable, whose flat and flexible characteristics encourage mobility
and easier storage. In this preferred embodiment, the main
difference from the device as shown in FIG. 7A is that there is no
lens that focuses light carried by optical fibers. Data are carried
by electrical wires that are lined within the outer shell and
within device 720.
[0102] Electric pins 730 or other means of making contact with
circuitry components may also be used as a connection interface
alternate to that of the ribbon cable. In some embodiments, device
720 can be connected to the mainframe by inserting a connector 724
of electric ribbon cable 722 into a socket 726 present on outer
shell 728 of the device. Socket 726 would have a shape that differs
from that for a flat interface, according to the shape of connector
724 shown in FIG. 7B.
[0103] FIG. 8A is a schematic showing a cross-sectional view of a
preferred embodiment of the user end device taken along A-A'
direction of FIGS. 7A and 7B, captured at an arbitrary time in
accordance to this invention, In FIG. 8A, wherein a user's breast
800 has been placed into an inner cavity 802 of the device for
self-examination. In a simplified representation, four panels 804
of broadband sources (out of at least one broadband source) are
symmetrically shown in this embodiment. A panel 806 of detectors
(out of at least one detector) is also shown. Source panel 804 and
detector panel 806 are not to scale, but it would be possible to
contain components as large as those depicted between outer shell
808 and inner cavity 802. For purposes of illustration and not for
limitations, only one of the panels of sources emitting light 810,
is shown in FIG. 8A. The light emitted is of a broadband spectrum,
which carry a range of wavelengths relevant to the analysis of
interested materials present (e.g., any tumor tissues, water,
hemoglobin, lipids). The outer surfaces of source panel 804 and
detector panel 806 are enlarged as shown in FIG. 8B.
[0104] Emitted light 810 travels across cavity 802 and interacts
with breast tissue 800. Within breast tissue 800, two arbitrary
volumes of tissues are illustrated: an area with normal tissue 816
(empty circle) and an area with potentially malignant tissue 818
(hatched circle). Depending on the size of potentially malignant
tissue 818, light 810 incident on it, light 810 will be diffracted,
reflected, or fluoresced. Assuming that potentially malignant
tissue 818 is smaller than the wavelength of emitted light 810, the
light will scatter into multiple directions. One such light wave
820 is shown traveling back to inner surface 822 toward panel of
detectors 806. If detector 814 is enabled (for example, the filter
allows) to detect the particular wavelength of light wave 820, it
then processes the signal for imaging or sends it to the mainframe
(not shown here) for further processing and imaging. Based on known
values of wavelengths that would be returned after reflecting or
diffracting from cancer tumors rather than known values of
wavelengths that would be returned after reflecting off healthy
tissue, the processor can determine the position and depth of the
returning light to locate potentially cancerous lesions.
Three-dimensional images can also be produced from all returning
light waves, with which potential cancerous lesions can be viewed
and interpreted on a display.
[0105] FIG. 8B is a schematic showing a magnified view of the
source panel 804, shown in FIG. 8A. It is an illustrative of
6.times.6 array of sources 812 embedded, with each source 812
producing multispectral light 810 toward cavity 802. Alternatively,
each source 812 in panel 804 can have the fixed wavelength of
lights or have different wavelengths, arranged in either 1-D or 2-D
array format. Any n by n or n by m array format for sources (not
shown here) can be also be used to make source panel 804.
[0106] FIG. 8C illustrates a magnified view of detector panel 806.
It is an illustrative 6.times.6 array of detectors 814 embedded,
and each detector 814 receiving diffracted, reflected, or
fluoresced light 820 from cavity 802, after the light is return
from the breast tissue or body surface. Numerous combinations of
source 812 and detector 814 placements can be used (not shown
here)
[0107] FIG. 9 is a schematic showing a cross-sectional view of an
alternate preferred embodiment for non-contact embodiment of the
user end of the device, taken along A-A' direction of FIGS. 7A and
7B, captured at an arbitrary time according to this invention,
wherein like parts are indicated by like reference numerals as used
in FIG. 8A, so that repeated explanation is omitted here. The main
difference from FIG. 8A is that individual detectors 924 are lined
throughout along the inner surface in FIG. 9, rather than grouped
in a panel. In a simplified representation, four panels of
broadband sources 904 (out of at least one broadband source) are
symmetrically shown in this embodiment. A selected number of
detectors 930 (out of numerous) is also shown. Multispectral
(having different wavelengths) light 910 travels from panel of
sources 904 to a user's breast tissue 900 placed in a cavity 902.
Within breast tissue 900, two arbitrary volumes of tissues are
illustrated: an area with normal tissue 916 (empty circle) and an
area with potentially malignant tissue 918 (hatched circle).
Assuming that potentially malignant tissue 918 is smaller than the
wavelength of emitted light 910, the light will scatter into
multiple directions. One such light wave 920 is shown traveling
back to inner surface 922 toward detector 924. If detector 924 is
enabled to detect the particular wavelength of light wave 920 (for
example, the filter allows it), it then processes the signal for
imaging or sends it to the mainframe for further processing and
imaging.
[0108] FIG. 10 is a schematic showing a cross-sectional view of a
preferred non-contact embodiment of the user end of the device,
taken along A-A' direction of FIGS. 7A and 7B, captured at an
arbitrary time, according to this invention, wherein like parts are
indicated by like reference numerals as shown in FIGS. 8A and 9, so
that repeated explanation is omitted here. The main difference from
FIG. 8A is that in FIG. 10, both light sources 1026 and detectors
1024 are placed individually in alternating fashion (1:1, 2:1, or
mixed in other ratios) throughout an inner surface 1022, rather
than grouped in a panel. In a simplified representation, two
broadband sources 1026 (out of numerous) and two detectors 1024
(out of numerous) are shown in this embodiment. Multispectral light
1010 travels from source 1026 to a user's breast tissue 1000.
Within breast tissue 1000, two arbitrary volumes of tissues are
illustrated: an area with normal tissue 1016 (empty circle) and an
area with potentially malignant tissue 1018 (hatched circle).
Assuming that potentially malignant tissue 1018 is smaller than the
wavelength of emitted light 1010, the light will scatter into
multiple directions. One such light wave 1020 is shown traveling
back to inner surface 1022 toward detector 1024. If detector 1024
is able to detect the particular wavelength of light wave 1020, it
then processes the signal for imaging or sends it to the mainframe
for further processing and imaging. From the aforementioned
disclosures, other useful configurations will be apparent to those
having ordinary skill in the art.
[0109] FIG. 11A shows a top view of alternate preferred non-contact
embodiment of the device, which has panes that can fold and unfold
into compact or useable forms ("flip-open non-contact embodiment").
According to this invention, to make the device compact, the device
comprises at least one foldable pane amenable to handheld use and
transportation. Alternatively, the device can have more than one
pane, wherein each pane 1100, 1102 holds detectors 1104, light
sources 1106, or both (see FIG. 11B). In this embodiment, center
pane 1100 holds light sources facing breast tissue 1108. Hinges
1110 allow panes 1102 on the side to flip open horizontally along
arcs 1112 and be held at desired angles relative to center pane
1100. This results in side panes 1102 facing breast tissue 1108.
There may be a handle 1114 or other means to grasp the device
during operation.
[0110] FIG. 11B is a schematic showing a front view of preferred
embodiment for flip-open non-contact device according to this
invention, wherein like parts are indicated by like reference
numerals as shown in FIG. 11A, so that repeated explanation is
omitted here. In FIG. 11B, side panes 1102, having panels of
detectors 1104, have been unfolded and are facing outward. Sources
1106 are individually placed on center pane 1100, although they may
be grouped together in panels and may be broadband or uniband
sources (see FIGS. 4-6). Alternatively other variations of
placement of sources 1106 and detectors 1104 are possible, for
example, as illustrated in FIG. 11C. Here, the main difference from
FIG. 11B is that sources 1106 are individually placed on side panes
1102 instead of one center pane 1100. Center pane 1100 comprises
panel of detectors 1104.
[0111] During operation of the flip-open non-contact embodiment,
the user places the device with panes 1100, 1102 opened over her
breast tissue 1108. The user may require manual operation to
receive sufficient data to image the interior of breast 1108 and
any areas of interest. For instance, the user may slowly move the
handheld device vertically or horizontally over her breast over a
certain path to "scan" it. Unlike other preferred embodiments
previously disclosed in FIGS. 8, 9 and 10, there is no need to
place one's breast inside an unseen cavity of a device. In the
embodiment illustrated in FIG. 11A, while the device is in
operation, broadband or uniband light sources 1106 from center pane
1100 emit light 1116 of varying wavelengths toward the object
placed between the side panes, in this case, breast 1108. In this
illustration, one pane 1100 of sources and two panes 1102 of
detector panels 1104 make up the handheld device. Reflected or
diffracted light 1118 travels back to a detector or panel thereof,
on side panel 1102. If the detector is able to detect the
particular wavelength of the light wave, it then processes the
signal for imaging or sends it to the mainframe (not shown) via
optical, electrical, or wireless connection for further processing
and imaging. Based on known values of wavelengths that would be
returned after reflecting or diffracting from cancer tumors rather
than known values of wavelengths that would be returned after
reflecting off healthy tissue, the processor can determine the
position and depth of the returning light to locate potentially
cancerous lesions. Three-dimensional images can also be produced
from all returning light waves; thus, potentially cancerous lesions
can be viewed and interpreted with human eyes.
[0112] One way to protect the user from over exposure to light is
to place shields between the user's line of sight and light
sources. FIG. 12A is a schematic showing a top view of the
preferred embodiment for alternate device, according to this
invention, wherein like parts are indicated by like reference
numerals so that related explanation is omitted here. The main
difference between FIGS. 12A and 11A is that in FIG. 12A, shields
1200 are placed over panes 1100, 1102. Shields 1200 are deployed by
unfolding them upward from panes 1100, 1102 along arcs 1202. They
may be composed of any material that will not be penetrated by the
light wavelengths that are used by the device. Such a material
should absorb rather than reflect. Alternatively, shields 1200 can
be made from materials that can prevent light from partially or
wholly escaping outside, such as a polymer, plastic, nano-composite
fiber, carbon fiber, etc. Similar to panes 1100, 1102, shields 1200
can be adjusted and held at desired angles. In the illustration,
engaged shields 1200 are locked into a substantially perpendicular
angle with respect to panes 1100, 1102. The usage of shields 1200
and placement of breast tissue 1108 within the enclosure created by
panes 1100, 1102 and shields 1200 decreases the leakage of light
from light sources 1106 (see FIGS. 11B, 11C, 12B, 12C). In turn,
the user is less likely to be irritated by light that she may see
or by wavelengths that may be harmful to the eyes during operation.
The shield can be made from the material the type of which can be
selected from the group consisting of polymer, plastic,
nano-composite having the capability of absorbing the light having
wavelengths to be absorbed. Alternatively, the shield can be made
from the material which could be reflective for the light
wavelengths of interest. In this case, the secondary reflective
light from the shield are made to incident onto the detector(s)
array (not shown here) for further processing the signal. The
signal can be synchronized or asynchronized with the main detector
panel described earlier. In this case, the shields can be designed
in such a way that incoming light and outgoing light (reflective)
can be same direction or different direction (not shown here).
Similar to FIG. 11A, hinges 1110 allow panes 1102 on the side to
flip open horizontally along arcs 1112 and be held at desired
angles relative to center pane 1100. This results in side panes
1102 facing breast tissue 1108. There may be a handle 1114 or other
means to grasp the device during operation.
[0113] FIG. 12B is a schematic showing the device with front shield
1200, as shown in FIG. 12A, according to this invention, wherein
like parts are indicated by like reference numerals so that related
explanation is omitted here. In FIG. 12B, side panes 1102, having
panels of detectors 1104, have been unfolded and are facing
outward. Sources 1106 are individually placed on center pane 1100,
although they may be grouped together in panels and may be
broadband or uniband sources as shown in FIGS. 4 to 6. Shields 1200
prevent light emitted by the sources from reaching the user's line
of sight which remains obstructed by shields 1200 during normal
operation. FIG. 12C is a schematic showing the same embodiment. The
main difference from FIG. 12B is that sources 1106 are individually
placed on two side panes 1102 instead of one center pane 1100,
while center pane 1100 comprises panel of detectors 1104. From the
aforementioned disclosures, other useful configurations will be
apparent to those having ordinary skill in the art.
[0114] FIGS. 13A and 13B are schematics showing the angled views of
a preferred embodiment with a self-adjusting cavity, before and
after the inner shell conforms to the shape of an object within a
cavity 1300 (hereinafter, this embodiment is referred to as a
"self-adjusting contact embodiment"), according to this invention.
Here, the surface of inner shell 1302 makes direct contact with a
breast placed in cavity 1300. In the neutral state, inner shell
1302 is close in proximity to outer shell 1304; inner shell 1302 is
nearly at the surface of outer shell 1304. After slabs along inner
shell 1302 determine the distance between itself and the breast, as
further described below (see below FIG. 14A and accompanying
disclosure), inner shell 1302 adjusts its surface to conform to the
shape of the breast in cavity 1300. As the inner circumference of
inner shell 1302 decreases, an area 1306 between outer shell 1304
and inner shell 1302 stretches, unfolds, or otherwise expands to
maintain the physical continuity of the device. The states of the
device before and after conforming to the breast are shown in FIG.
13A and FIG. 13B, respectively. The degree to which this
adaptability is feasible is at least partly based on the material
comprising area 1306 between inner shell 1302 and outer shell 1304.
A flexible, rubber-based, or fabric-based material may allow
greater movement. A difference in radius is indicated by line 1308.
This self-adjustment results in inner surface 1302 directly
contacting the breast.
[0115] FIG. 14A is a schematic showing a cross-sectional view of
the self-adjusting contact embodiment of the user end of the device
whose inner cavity 1300 self-adjusts to an object (i.e., breast)
placed within, taken along B-B' direction of FIG. 13A and FIG. 13B,
according to this invention, wherein, like parts are indicated by
like reference numerals as used previously, so that repeated
explanation is omitted here. Here, inner surface 1302a is comprised
of numerous slabs 1400 overlapping one another at least partially.
Slabs 1400 are connected in a circular ring that extends
circumferentially with respect to a center axis 1412. Each slab
1400 has electrical wires or optical fibers 1402 running along the
interior of each slab 1400 and/or between inner shell 1302 and
outer shell 1304. Fibers or wires 1402 are connected to sources and
detectors (not shown here) on the bottom surface of slabs 1400. The
sources and detectors point substantially toward center axis 1412
of cavity 1300 and emit or receive light 1404 along illustrative
paths 1406.
[0116] FIG. 14B is a schematic showing an enlarged illustrations of
slabs 1400 in portions 1408a and 1408b from FIG. 14A, according to
this invention. It is a front-top perspective, as if one were
looking into the center of cavity 1300, and the two panels are
moving sideways relative to that perspective. Slabs 1400 wrap
around the circumference of cavity 1300, extending outward and
inward relative to the plane of the illustration in FIG. 14B.
Guiding arrows 1410 point in the same absolute direction to assist
in understanding the orientation of the components. From a front
perspective, each ring of slabs 1400 interacts with adjacent rows,
which extend inward and outward of the cavity, or farther or
closer, respectively, relative to the aforementioned perspective.
When slabs 1400 slide under each other the following parameters
decrease: distance 1416 between slabs 1400, the circumference and
radius of the ring of slabs 1400, and the surface area of inner
surface 1302a. These changes cause inner shell 1302a to move toward
center axis 1412 of the device, resulting in a shrunken inner
surface 1302b.
[0117] Each slab has a source that emits light 1404 in the visible
range, which allows each panel to determine the distance between
itself and the object when the light reflects back. The
illustration demonstrates three occurrences of this (in dashed
boxes), and the distances calculated between the breast and three
slabs are shown. A line 1414a indicates the distance between
portions 1408a and 1408b. Other lines 1414b, 1414c show the
distances between other points of inner shell 1302a and breast
1410. When the distance between slab 1400 and breast 1410 are
recognized, slabs 1400 slide the appropriate distance among
themselves, shrinking the surface area of inner shell 1302a and
thus the volume of cavity 1300. Area 1306 of the device between
outer shell 1304 and inner shell 1302 is composed of a flexible
material, such as cloth or rubber, or polymer. As the inner
circumference decreases, area 1306 stretches, unfolds, or otherwise
expands to allow inner surface 1302 to conform to breast 1410. Such
self-adjustment results in distances 1414a, 1414b, 1414c
approaching zero and shrunken inner surface 1302b directly
contacting breast 1410.
[0118] FIGS. 15A and 15B are schematics showing a front view and an
angled view, respectively, of a preferred embodiment of the user
end of the device which has a surface 1500 that makes direct
contact with the breast ("flexible contact embodiment"), according
to this invention. In this embodiment, the device has a broad "C"
shape and is connected to a mainframe (not shown here) via a cable
1502, which represents a bundle of optical fibers, an electronic
connection, or a wireless connection. The mainframe contains a
processor and generates light signals or corresponding electrical
signals for the handheld device. The open portion of the device has
surface 1500, which is the user end of the handheld apparatus. The
interior of the device houses all the components of the handheld
device. The outer walls of the device are composed of a flexible
polymer or any light and sturdy material. Surface 1500 is curved in
a manner that accommodates for almost all breast sizes and
curvatures. Surface 1500 is lined with light sources 1504 and
detectors 1506 or panels thereof that emit and detect light 1208.
The user may adjust the curvature of surface 1500 by bending the
top and bottom edges of the device, as indicated by arrows 1512,
and the material may allow the device to retain the customized
shape for at least a period of time required for self-diagnosis.
While surface 1500 possesses substantial curvature, it is also
relatively flat compared to the hemispheric embodiments as shown in
FIGS. 7A-10. The relatively flat surface causes emission of light
waves 1508 in a relatively similar direction with fewer overlapping
light waves than would if it were emitted into a cavity as shown in
FIGS. 7A-10. Detecting returning light 1510 is also performed by
the flat surface. The user may require manual operation of the
handheld device to receive sufficient data to image the interior of
the breast and any areas of interest. For instance, the user may
need to slowly move the handheld device across her breast over a
certain path to "scan" it. The distinctions between the embodiments
employing optical fibers and electrical wires are disclosed
immediately below.
[0119] FIG. 16A is a schematic showing a cross-sectional view of a
preferred embodiment for a flexible contact embodiment using
optical fibers, taken along C-C' direction of FIG. 15, according to
this invention. FIG. 16A illustrates a cross-section from FIG. 15
before a breast 1600 makes contact with surface 1500 for optical
imaging. The curvature of the interface between breast 1600 and
device is more apparent from this perspective. The interior of the
device contains individual 1:1 fiber or wire connections 1602
between cable 1502 and a light source or detector.
[0120] Each source- or detector-to-cable optical fiber 1602
connects and transfers data from one source or detector on surface
1500 to the mainframe. Between the mainframe and the user end may
be a lens 1604 that focuses light signals before sending them
through cable 1502. Fibers 1214 are bundled into cable 1502, which
connects to the mainframe. The top and bottom edges of the device
may be adjusted to user preference by bending it toward and away
from the user, as indicated by arrows 1512.
[0121] FIG. 16B is a schematic showing the same cross-sectional
view of a flexible contact embodiment but using electrical wires.
The main difference from FIG. 16A is that in FIG. 16B, a socket
1606 and a connector 1608 for a detachable electric ribbon cable
1610 are used to separate the user end from the mainframe. Electric
pins or other means of making contact with circuitry components may
also be used (see FIG. 16C). The distinctions between embodiments
employing optical fibers and electrical wires are described above
for FIGS. 7A and 7B.
[0122] FIG. 16C is a schematic showing an enlarged view of the
front of connector 1608 of electric ribbon cable 1610, which allows
connection to socket 1606 via electric pins 1612 as a connection
interface alternate to that of the ribbon cable. Socket 1606 would
have a shape that differs from that for a flat interface, according
to the shape shown in FIG. 16B.
[0123] FIG. 17A is a schematic showing a cross-sectional view of a
preferred embodiment for a flexible contact embodiment, taken along
C-C' direction of FIG. 15 after the breast tissue makes contact
with the surface for optical imaging, according to this invention,
wherein, like parts are indicated by like reference numerals as
used previously, so that repeated explanation is omitted here.
Here, the user has pressed the device onto breast 1700 for
self-examination. Breast tissue 1700 makes contact with an outside
surface 1500 of the device along area 1702. In a simplified
representation, two panels 1704 of broadband sources (out of at
least one broadband source) are symmetrically shown in this
embodiment. They are embedded on outside surface 1500 of the device
such that sources 1704 generate and emit optical signals outwardly,
and all the components are inside the device, behind surface 1500.
Another panel 1706 of detectors (out of at least one detector) is
also shown in the same manner. Sources 1704 and detector 1706 are
not to scale, but it would be possible to contain components as
large as those depicted on the interior side of surface 1500.
[0124] For purposes of illustration, each panel of sources 1704
emits light 1708 in different angles. Light 1708 emitted is of a
broadband spectrum, i.e., it carries a range of wavelengths
relevant to the analysis of interested materials present (e.g.,
tumor tissues, water, hemoglobin, lipids). The outer surfaces of
source panel 1704 and detector panel 1706 are enlarged as shown in
FIGS. 17B and 17C as 6.times.6 arrays of sources 1710 and detectors
1712 embedded in their respective panel surfaces, with each source
1710 producing multispectral light 1708. Emitted light 1708 then
interacts with breast tissue 1700. Within breast 1700, two
arbitrary volumes of tissues are illustrated: one volume of normal
tissue 1714 and one volume of potentially malignant cells 1716
(later determined with greater confidence by analyzing returned
information). Depending on the size of potentially malignant tissue
1716, light 1708 hitting it will be diffracted or reflected.
Assuming that tissue 1716 is smaller than the wavelength of emitted
light 1708, light 1708 will scatter into multiple directions. If
tissue 1716 is larger than the wavelength, light 1708 will be
reflected. One scattered light wave 1718 is illustrated to be
traveling back to interface surface 1500 toward panel of detectors
1706. In reality, light 1718 will be scattered in numerous
directions in a spherical shape. If detector 1706 is able to detect
at least one particular wavelength, it then processes the optical
signal for imaging or sends it to the mainframe for further
processing and imaging. Based on known values of wavelengths that
would be returned after reflecting or diffracting from cancer
tumors rather than known values of wavelengths that would be
returned after reflecting off healthy tissue, the processor can
determine the position and depth of the returning light to locate
potentially cancerous lesions. Three-dimensional images can also be
produced from all returning light waves; thus, potentially
cancerous lesions can be seen and interpreted with human eyes.
[0125] FIG. 18 illustrates a cross-sectional view of another
preferred flexible contact embodiment of the user end of the device
at an arbitrary time of operation. Like parts are indicated by like
reference numerals as used previously, so that repeated explanation
is omitted here. The main difference from FIG. 17A is that
individual detectors 1800 are lined throughout interface surface
1500, rather than grouped in a panel. In a simplified
representation, two panels of broadband sources 1704 (out of at
least one broadband source) are symmetrically illustrated in this
embodiment. A selected number of detectors 1800 (out of numerous)
are also shown. Multispectral light 1708 travels from panels of
sources 1704 to breast tissue 1700. Assuming that potentially
malignant tissue 1716 is smaller than the wavelength of the emitted
light, light 1708 will scatter into multiple directions. One
scattered light wave 1718 is illustrated to be traveling back to
interface surface 1500 toward one detector 1800. If detector 1800
is able to detect at least one particular wavelength, it then
processes the optical signal for imaging or sends it to the
mainframe for further processing and imaging.
[0126] FIG. 19 is a schematic showing a preferred embodiment
according to this invention, wherein like parts are indicated by
like reference numerals so that repeated explanation is omitted
here. The main difference from FIG. 18 is that light sources 1900
and detectors 1800 are placed individually in alternating fashion
throughout inner surface 1500, rather than grouped in a panel. From
the aforementioned disclosures, other useful configurations will be
apparent to those having ordinary skill in the art.
[0127] Operational accuracy of the device can be improved by using
a supplementary layer between the surface of the breast and the
device. Refractive index n plays a role in characterizing
biological tissues' response to optical illumination. The layer
acts as an intermediary between two media of dissimilar refractive
indices. For example, there is a disproportionate disparity between
air and tissue if approximately n of air is 1.00, n of epidermis is
1.41, n of dermis is 1.36, and n of fatty tissue is 1.45. A medium
with sufficiently disparate refractive index will tend to reflect
light incident on that medium. The supplementary layer serves to
introduce an intermediate n that mediates and bridges the gap
between the disparate values between air and tissue, i.e.,
approximately between 1.00 and refractive indices of tissue
components. Since the light incident must penetrate, the layer is
transparent to light wavelengths of interest and reduces
reflection. The layer is thin relative to the tissue, non-hazardous
to the skin, and is easily removed or washed. The layer helps
smooth out the target surface area of the breast, reducing
variability and standardizing the experience among users of the
device, because there may be different skin types, amount of hair
present, and smoothness. Flattening the skin above the area of the
breast the device operates on can reduce interference from
microscopic obstacles and gaps present on the surface of the skin.
The supplementary layer may be embodied and used in various ways as
disclosed below.
[0128] FIG. 20A illustrates a cross-sectional view of a section of
skin 2000 above the breast and a gel layer 2002. A thin layer of
gel 2002 is applied on the surface of section of skin 2000 over
which the device will be placed. The thickness of the layer of gel
2002 is exaggerated to show the amorphous nature of gel 2002. It is
easily washed from the skin as well as the device if the device has
touched the gel. FIG. 20B is a highly enlarged cross-sectional view
of the same section of skin 2000 as FIG. 20A. The main difference
from FIG. 20A is that nanoparticles 2004 are embedded in gel 2002,
which may be composed of ZnO, TiO2, and/or other metal oxide
particles. Nanoparticles 2004 enable reduction or complete
alleviation of the reflection of light, which enhances the clarity
of images produced later.
[0129] FIG. 20C illustrates a cross-sectional view of skin 2000 and
a rigid layer 2006 pressing down on it. As with other forms of the
supplementary layer, rigid layer 2006 is transparent to wavelengths
of interest and is non-toxic to the skin. By applying force 2008
during application of rigid layer 2006, it flattens skin 2000 and
smoothes out the surface of skin 2000. This serves two purposes:
Reduce the reflection of light and the delta of refractive indices
between air and components of skin 2000, and reduce variability of
experience among different users. Rigid layer 2006 may be
constructed inexpensively to be disposable.
[0130] FIG. 20D illustrates a cross-sectional view of skin 2000 and
one side of a flexible layer 2010 pressing down on it. As with
other forms of the supplementary layer, flexible layer 2010 is
transparent to wavelengths of interest and is non-toxic to the
skin. Flexible layer 2010 may be extremely thin and malleable so as
to be wrapped or stretched over the target area of skin. Similar to
the rigid or gel embodiments as shown in FIGS. 20A-20C, flexible
layer 2010 is serves to reduce the gap between disparate n values
when light enters a different medium. By applying force 2012 toward
or away during application of flexible layer 2010, the user has
greater control over application of flexible layer 2010 as well as
determination of which area of skin to apply it to. Flexible layer
2010 may be constructed inexpensively to be disposable. FIG. 20E is
a schematic showing a top view of skin 2000 and a flexible layer
2010 as an alternative view of FIG. 20D. Top side 2010a of flexible
layer 2010 is shown, and bottom side 2010b is shown being lifted
from skin 2000. Flexible layer 2010 is malleable enough to be
folded and partially bent upward as illustrated.
[0131] FIG. 21 is a schematic showing a whole view of
implementations of operational parts of the preferred embodiment,
according to this invention. A user end 2100 is the handheld
portion for the user to aim and receive light. In embodiments using
optical fibers to transfer light signals, light 2102 may be
generated by sources placed in a mainframe 2104 rather than user
end 2100. Likewise, detectors may be placed in mainframe 2104
rather than user end 2100. In other embodiments, sources and
detectors may be placed on user end 2100, with a generic connection
2106a transferring data between the user end and the mainframe.
Instructions or data 2108 containing instructions to emit light
2102 may travel from mainframe 2104 to user end 2100. Data 2110 on
received light 2112 may travel from user end 2100 to mainframe
2104. Mainframe 2104 may include a processor 2114 and also other
components, such as light sources, detectors, display screen,
source driver, controller, signal amplifier, and digitizer (see
FIG. 2). Different means of transferring data are possible. In some
embodiments, connection 2106a between mainframe 2104 and user end
2100 is comprised of a bundle of optical fibers that transfer
light. In some other embodiments, the connection is comprised of
electrical wires, preferably a ribbon cable because it is highly
compact and flexible. In yet other embodiments, the connection is
wireless and lacks a physical connection.
[0132] In some embodiments, a display screen 2118 displays
diagnosis results, images, and other information 2116 the user may
be interested in. Display screen 2118 may be part of mainframe
1504, exist remotely on another apparatus dedicated to the device,
or be on the user's separate electronic device, such as a mobile
phone or a personal computer. User end 2100 communicates with
mainframe 2104 to exchange data and instructions 2108, 2110.
Various embodiments have different combinations wherein components
are placed in different places, as described below.
[0133] FIG. 22 is a schematic of a whole view of an embodiment,
according to this invention, wherein connection 2106b between user
end 2100 and mainframe 2104 is of electrical nature. Like parts are
indicated by like reference numerals as used previously, so that
repeated explanation is omitted here. The means of connection
transfer only electrical signals. It delivers instructions 2108
from processor 2114 within mainframe 2104, enabling particular
sources on user end 2100 to emit light 2102 at predetermined,
particular wavelengths and/or predetermined, particular times as
instructed. The detectors on user end 2100 register various
reflected or diffracted light waves 2112. Data collected 2110 is
transferred back to mainframe 2104, where useful data, such as
sizes of areas of interest, depths of areas of interest, and images
of the interior of the user's breast, are derived. Results derived
2116 can be displayed on screen 2118 for the user. Screen 2118 may
be part of mainframe 2104, separate from mainframe 2104, or it
could be on another device. For example, the screen may be on a
mobile phone or a monitor of a personal computer may connect to
mainframe 2104 and serve as the screen. Results 2116 may be sent to
such a separate device, or it may be displayed on screen 2118 as
part of mainframe 2104.
[0134] FIG. 23 is a schematic of a preferred embodiment, according
to this invention, wherein like parts are indicated by like
reference numerals as used previously, so that repeated explanation
is omitted here. The main difference from FIG. 22 is that here,
results 2116 are transferred to and displayed on a separate device
or screen 2118, whereas all functions described in FIG. 22 are
performed at the user end, i.e., user end 2100 contains the
processor, sources, and detectors. Display screen 2118 is
electrically connected to user end 2100.
[0135] FIG. 24 is a schematic diagram of a whole view of an
embodiment, wherein the connection between user end 2100 and
mainframe 2104 is of optical nature, able to transfer light. Like
parts are indicated by like reference numerals as used previously,
so that repeated explanation is omitted here. Here, instructions
originate from user end 2100, and the sources operate to emit light
2102 at predetermined, particular wavelengths and/or predetermined,
particular times. User end 2100 collects returning light waves
2112, which are directly transferred to mainframe 2104 via
optical-fiber cable 2106c. Light received 2112 at the user end may
be focused by a lens (not shown here) before being directly
transferred through optical-fiber cable 2106c. Received optical
signals 2112 are detected by detectors 2120, or a panel thereof,
within mainframe 2104. Detected optical signals are processed to
derive useful data 2116, such as confirming possible tumors, its
size and location, and images of the interior of the user's breast
tissue. These data 2116 may be presented on display screen 2118.
Screen 2118 may be part of mainframe 2104, separate from it, or it
could be on another device. For example, the screen may be on a
mobile phone or a monitor of a personal computer.
[0136] As a variation of this embodiment, in FIG. 25, optical-fiber
cable 2106c transfers both emitted light 2102 and returning light
2112. Like parts are indicated by like reference numerals as used
previously, so that repeated explanation is omitted here. The main
difference from FIG. 24 is that in this embodiment, mainframe 2104
comprises both sources 2122 and detectors 2120. Using the unique
properties of optical fibers, optical-fiber cable 2106c acts as a
waveguide for light 2102, 2112 emitted from and returned to
mainframe 2104, where the data is processed. In this embodiment,
user end 2100 does not have any sources or detectors. It only acts
as a mechanism to collect and focus light that is emitted and
returned. As in the embodiment of FIG. 24, results 2116 may be sent
to a separate device, or it may be displayed on screen 2118 as part
of mainframe 2104.
[0137] FIG. 26 is a schematic of a preferred embodiment wherein the
connection between user end 2100 and mainframe 2104 is wireless.
Instructions 2108c to generate light 2102 and data 2110c on
detected light 2112 are transmitted by wireless means. Instructions
2108c are generated from mainframe 2104, enabling particular
sources on user end 2100 to emit light 2102 at predetermined,
particular wavelengths and/or predetermined, particular times as
instructed. The detectors on user end 2100 register various
reflected or diffracted light waves 2112. Data 2110c collected is
transferred wirelessly back to mainframe 2104, where useful data
2116, such as sizes of areas of interest, depths of areas of
interest, and images of the interior of the user's breast, are
derived. The results derived can be displayed on screen 2118 for
the user. Screen 2118 may be part of mainframe 2104, separate from
it, or it could be on another device. For example, the screen may
be on a mobile phone or a monitor of a personal computer.
[additional technical details on wireless functions?].
[0138] FIG. 27 is a schematic diagram of an embodiment in which all
functions described in the previous FIG. 26 are performed at user
end 2100, i.e., user end 2100 contains the processor, sources, and
detectors. Like parts are indicated by like reference numerals as
used previously, so that repeated explanation is omitted here. The
main difference from FIG. 26 is that results 2116 are transferred,
not from a separate mainframe but directly from user end 2100, to
and displayed on a separate device or screen 2118. Display screen
2118 is connected to user end 2100 via wireless means.
[0139] FIG. 28 is a schematic showing a close-up view of an
optical-fiber cable 2800, which comprises a bundle of optical
fibers 2802. Numerous optical fibers 2802 are packed into cable
2800. Optical fibers 2802 are transparent and highly flexible
fibers that are typically at most 0.5 mm. They can function as a
waveguide for light 2804 traversing through. Containment of light
2804 is enabled by total internal reflection, which completely
reflects light propagating along fiber 2802 hits the boundary of
fiber 2802 at a critical angle, ideally close to parallel with the
walls of fiber 2802. To confine and propagate light 2804 within
fiber 2802, the light that enters cable 2800 must be within a
certain range of angles, which a lens (see FIGS. 7A, 16A) assists
with.
[0140] FIGS. 29A-29C are schematic diagrams of various examples of
shapes of devices and manufactures in which the functions disclosed
thus far may be implemented. FIG. 29A shows an example of an
embodiment of a device that implements the present invention. A
satellite-shaped device 2900a having a ball-and-socket joint 2902
between a user end 2904 and a handle 2906 is shown. User end 2904
is cup shaped and may implement at least the non-contact and
contact embodiments shown in FIGS. 7A-10 and 13-19, enabling
versatile use for multiple purposes and usage methods. In this
embodiment, a control panel 2908 is shown on handle 2906, but it
may be placed anywhere that allows convenient operation. Control
panel 2908 may also include a display screen 2910. Control panel
2908 may include user-controlled switches that enable certain
functions, such as a power button, an operation button that moves
user end in various directions shown by arrows 2912, an operation
button that enables an inner surface 2914 to conform to the size of
the user's breast, and other peripheral devices. Other
configurations and arrangements of elements shown here are possible
and will be apparent to those having ordinary skill in the art.
[0141] FIG. 29B shows another example of an embodiment of a device
that implements the present invention. A top view of a flip-open
non-contact type device 2900b having a center pane 2916 and side
panes 2918 is shown. As described in the text accompanying FIGS.
11-12, each pane 2916, 2918 has sources or detectors, or both, or
panels thereof. The capability to adjust pane angles introduces
compactness and flexibility in operating the device depending on
the size and location of the breast. This type of device may
implement at least the flip-open non-contact embodiments shown in
FIGS. 11-12.
[0142] FIG. 29C shows another example of an embodiment of a device
that implements the present invention and may implement at least
the contact embodiments shown in FIGS. 15-19. A side view of a
flexible contact device 2900c having a user end 2920 is shown. An
interfacing side 2922 of flexible user end 2920 has a curved shape.
Flexible user end 2920 allows the user to press device 2900c
conform the breast to the shape of interfacing side 2922 of user
end 2920. To an extent, user end 2920 may conform to the shape of
the breast by virtue of its flexible construction. Direct contact
enhances the quality of data acquired with a smaller margin of
error. An example of a port 2924 is shown for connecting user end
2920 to other devices, such as a switch, control panel, display
screen, computing device, and other peripheral devices, all of
which may reside within user end 2920.
[0143] Features present in FIGS. 29A and 29C may be modified or
combined in other ways. For example, the satellite-shaped device of
FIG. 29A may not have a rotatable ball-and-socket joint 2902,
fixing the open cavity to one direction. For example, the flexible
user end of FIG. 29C may be attached to an elongated handle similar
to handle 2906 in FIG. 29A.
[0144] The present invention is expected to be found practically
use in the hand held based non-invasive cancer screening system
where the broadband radiation is used to diagnosis initial stage of
the cancer diagnosis, covering breast, skin, etc. The application
includes not only hand held type diagnosis system, but also
combining with other detection system to increase the accuracy for
the small to medium scale system.
[0145] Specific embodiments or examples, given in the detailed
description of the present invention, are only used for clarifying
the technical contents of the present invention, and are not
narrowly interpreted in a limited manner to such specific examples,
and various modifications may be made therein within the spirit of
the present invention and the scope of the following claims.
* * * * *