U.S. patent application number 13/129171 was filed with the patent office on 2011-10-13 for needle with optical fibers.
This patent application is currently assigned to KONINKLIJKE PHILIPS ELECTRONICS N.V.. Invention is credited to Augustinus Laurentius Braun, Adrien Desjardins, Rik Harbers, Bernardus Hendrikus Wilhelmus Hendriks, Rami Nachabe, Marjolein Van Der Voort.
Application Number | 20110251494 13/129171 |
Document ID | / |
Family ID | 41480178 |
Filed Date | 2011-10-13 |
United States Patent
Application |
20110251494 |
Kind Code |
A1 |
Hendriks; Bernardus Hendrikus
Wilhelmus ; et al. |
October 13, 2011 |
NEEDLE WITH OPTICAL FIBERS
Abstract
Needle interventions are widely used in the field of oncology
for taking biopsies of tissue in order to inspect whether tissue is
cancerous or not. To make these interventions more reliable
feedback of what kind of tissue is in front of the needle is
required. A way to achieve this is by making use of optical
spectroscopy. This requires integration of fibers into the needle.
These fibers are used to deliver light to illuminate the tissue in
front of the needle and to collect back the reflected light from
the tissue. The present invention proposes to integrate the fiber
distal ends in the slanted bevel of the needle in such a way that
at least one source-detector fiber pair has a distance that is
larger than the outer diameter of the needle.
Inventors: |
Hendriks; Bernardus Hendrikus
Wilhelmus; (Eindhoven, NL) ; Braun; Augustinus
Laurentius; (Heeze, NL) ; Harbers; Rik;
(Zurich, CH) ; Van Der Voort; Marjolein;
(Eindhoven, NL) ; Desjardins; Adrien; (Eindhoven,
NL) ; Nachabe; Rami; (Eindhoven, NL) |
Assignee: |
KONINKLIJKE PHILIPS ELECTRONICS
N.V.
EINDHOVEN
NL
|
Family ID: |
41480178 |
Appl. No.: |
13/129171 |
Filed: |
November 18, 2009 |
PCT Filed: |
November 18, 2009 |
PCT NO: |
PCT/IB2009/055128 |
371 Date: |
May 13, 2011 |
Current U.S.
Class: |
600/478 |
Current CPC
Class: |
A61B 18/1477 20130101;
A61B 2018/1425 20130101; A61B 10/0283 20130101; A61B 5/0075
20130101; A61B 5/0084 20130101; A61B 2017/00057 20130101; A61B
5/1459 20130101; A61B 17/3401 20130101; A61B 5/6848 20130101; A61B
10/0233 20130101 |
Class at
Publication: |
600/478 |
International
Class: |
A61B 6/00 20060101
A61B006/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 19, 2008 |
EP |
08169409.3 |
Claims
1. A needle (100, 200) comprising a shaft (110, 210), a tip at a
distal end of the shaft, wherein the tip of the needle is formed by
a bevel (120, 220), a first fiber (130, 230), the first fiber being
capable of transmitting light, wherein an end surface (132, 232) of
the first fiber is located at a top (122, 222) of the bevel, and a
second fiber (140, 240), the second fiber being capable of
transmitting light, wherein end surface (142, 242) of the second
fiber is located at a bottom (124, 224) of the bevel.
2. The needle of claim 1, wherein the shaft (110, 210) has an outer
diameter (D), wherein the end surface (132, 232) of the first fiber
and the end surface (134, 234) of the second fiber are arranged at
a distance (A) to each other, wherein the distance (A) is greater
than the diameter (D).
3. The needle of claim 2, wherein the distance (A) is more than 1.5
times greater than the diameter (D).
4. The needle of claim 2, wherein the outer diameter (D) of the
shaft (110, 210) is between 0.711 mm and 2.108 mm.
5. The needle of claim 1, wherein the bevel (120, 220) forms an
acute angle (b) with the shaft (110, 210), such that the needle
includes a pointed tip.
6. The needle of claim 5, wherein the acute angle (b) is
20.degree..
7. The needle of claim 1, further comprising a third fiber, the
third fiber being capable of transmitting light, wherein an end
surface (252) of the third fiber is located at the bottom (224) of
the bevel in the vicinity of the end surface (242) of the second
fiber.
8. The needle (300) of claim 1, further comprising an inner tube
(352) and an outer tube (350), wherein a space (356) is formed
between the inner tube and the outer tube, wherein the fibers (330,
340) are accommodated in the space.
9. A system for optical tissue inspection, the system comprising a
needle (100, 200, 300) according to claim 1, a light source (332)
connected with one of the fibers (330) of the needle (300), a light
detector (342) connected with another one of the fibers (340) of
the needle (300), wherein light coming from the light source and
being emitted from the end surface of the one of the fibers can be
detected by the light detector when entering the other one of the
fibers, a processing unit (370) for processing the data from the
light detector, and a monitor (380) for visualization of the
processed data.
Description
FIELD OF THE INVENTION
[0001] The invention generally relates to a needle with optical
fibers. Particularly, the invention relates to a small diameter
needle for tissue inspection based on optical spectroscopy to
diagnose whether tissue is cancerous or not.
TECHNOLOGICAL BACKGROUND
[0002] Needle interventions are widely used in the field of
oncology for taking biopsies of tissue in order to inspect whether
tissue is cancerous or not. To make these interventions more
reliable feedback of what kind of tissue is in front of the needle
is required. A way to achieve this is by making use of optical
spectroscopy. This requires integration of fibers into the needle.
These fibers are used to deliver light to illuminate the tissue in
front of the needle and to collect back the reflected light from
the tissue.
[0003] An important feature that can be used in discriminating
tissue is the absorption peaks present in the reflectance spectra.
In general the absorption of tissue in the visible range is rather
low (typically the absorption coefficient .mu..sub.a=0.1
cm.sup.-1). This means that when the source-detector fiber ends are
close to each other, the effect of the absorption becomes rather
small on the spectra and as a result difficult to detect.
[0004] Various needle interventions such as taking biopsies could
benefit from this kind of tissue characterization in front of the
needle. However, these needle interventions have a strong drive to
have needles with an as small as possible outer diameter in order
to reduce the trauma of the patient as much as possible. As a
result, this drive towards small outer diameter needles is in
conflict with the requirement that the fibers should be as far as
possible apart in order to have detectable absorption features in
the measured reflectance spectra.
[0005] Various fiber optic probes are described in literature such
as in "Fiber optic probes for biomedical optical spectroscopy" by
U. Utzinger and R. R. Richards-Kortum in Journal of Biomedical
Optics volume 8 (2003) p121-147. These probes have in general blunt
probe ends resulting in fiber end distances that are smaller than
the diameter of the probe.
SUMMARY OF THE INVENTION
[0006] It might be an object of the invention to integrate the
source-detector fibers into the needle tip such that the outer
diameter of the needle is small while still having a detectable
absorption feature in the measured reflectance spectra.
[0007] These might be achieved by the subject matter according to
each of the independent claims. Further embodiments of the present
invention are described in the respective dependent claims.
[0008] Generally, a needle according to the invention comprises a
shaft, a tip at a distal end of the shaft, wherein the tip of the
needle is formed by a bevel, a first fiber, the first fiber being
capable of transmitting light, wherein an end surface of the first
fiber is located at a top of the bevel, and a second fiber, the
second fiber being capable of transmitting light, wherein end
surface of the second fiber is located at a bottom of the
bevel.
[0009] The bevel of the needle is in general slanted in order to
allow easy entry into the tissue. Therefore, with `bevel` is meant
a geometrical structure allowing for introducing the needle into
tissue. Usually, a shaft of a needle includes a circular cross
section. The distal end of a needle shaft, in particular of a shaft
of a hollow needle, is cut such that an oval surface is formed,
which is inclined relative to the longitudinal axis of the shaft.
Further, there is defined an angle between the longitudinal axis of
the shaft and the inclined surface, i.e. the bevel. The bevel forms
a pointed tip at the most distal end of the needle. Furthermore,
the edge between the outer surface of the shaft and the inclined
surface of the bevel might be sharpened.
[0010] The wording `top of the bevel` should indicate an area being
part of the surface of the bevel, which area is located adjacent to
the distal edge between the bevel and the shaft. That is, a fiber
which is located at the top of the bevel might be located at the
long axis of the oval surface of the bevel, near the distal edge,
i.e. the pointed tip.
[0011] On the other hand, `bottom of the bevel` means the area
being part of the surface of the bevel, which area is located
diametric to the top of the bevel. That is, the fiber which is
located at the bottom of the bevel might be on or near or adjacent
beside the long axis of the oval surface of the bevel near the
proximal edge between bevel and shaft.
[0012] However, the wording `bevel` might also enclose similar
structures at the tip of the needle, which structures are useful
for introducing the needle into a tissue. For example, the bevel
might be a convex or concave surface, or the bevel might be a
combination of several small surfaces, wherein these surfaces are
connected to each other by steps or edges. It might also be
possible that the cross section of the shaft is not completely cut
by the bevel, such that an area remains which is blunt, i.e. is
perpendicularly orientated relative to the longitudinal axis of the
shaft. Such a `blunt` end might include rounded edges or might also
form a rounded leading edge. As another exemplary, a sharp edge
might be formed by two or more slanted surfaces being symmetrically
or asymmetrically arranged to form the tip of the needle.
[0013] According to one embodiment of the invention, the bevel
forms an acute angle with the shaft, such that the needle includes
a pointed tip. Preferably, the acute angle is approximately
20.degree..
[0014] According to one embodiment of the invention, the shaft of
the needle has an outer diameter, and the end surface of the first
fiber and the end surface of the second fiber are arranged at a
distance to each other. Preferably, the distance between the fiber
ends is greater than the diameter of the shaft. For example, the
distance is more than 1.1 times greater than the diameter.
Particularly, the distance is more than 1.25 times greater than the
diameter. Preferably, the distance is more than 1.5 times greater
than the diameter.
[0015] Depending on the intended use of the needle, the outer
diameter of the needle might be 2.108 mm for a brain biopsy needle,
between 1.27 mm and 2.108 mm for a common biopsy needle or a neuro
puncture needle, between 0.711 mm and 2.108 mm for a fine
aspiration needle, between 0.711 mm and 1.473 mm for an epidural
needle, and might be 2.108mm or smaller for a needle electrode.
[0016] According to a further embodiment of the invention, the
needle further comprises a third fiber which is capable of
transmitting light, wherein an end surface of the third fiber is
located at the bottom of the bevel in the vicinity of the end
surface of the second fiber. In this case, the second fiber and the
third fiber might be located beside the long axis of the bevel
surface.
[0017] For example, with a needle diameter of 1.3 mm it might be
possible that the distance between the fiber at the top of the
bevel and one of the fibers at the bottom of the bevel might be
2.46 mm, and the distance between the two fibers at the bottom of
the bevel might be 0.37 mm.
[0018] It is noted that the distances are measured from the central
axis of one of the fibers to the central axis of the other one of
the fibers.
[0019] According to another embodiment of the invention, the shaft
of the needle is formed by an inner tube and an outer tube, wherein
a space is provided between the inner tube and the outer tube, in
which space the fibers are accommodated.
[0020] According to yet another embodiment of the invention, the
needle with fibers might be use in a system for optical tissue
inspection, wherein the system further comprises a light source
connected with one of the fibers of the needle, a light detector
connected with another one of the fibers of the needle, wherein
light coming from the light source and being emitted from the end
surface of the one of the fibers can be detected by the light
detector when entering the other one of the fibers, a processing
unit for processing the data from the light detector, and a monitor
for visualization of the processed data.
[0021] In such a system, the fiber distal ends in the needle
slanted bevel provide at least one source-detector fiber pair with
a distance A that is larger than the outer diameter of the needle
D, wherein A>1.1D or even A>1.25D, and preferably A>1.5D.
If b is the tip angle of the needle bevel the following equation
might count
A D > sin b + 0.1 sin b ( 1 ) ##EQU00001##
[0022] In the case that the needle is provided with a first fiber
at the top of the bevel, and with second and third fibers at the
bottom of the bevel, the first fiber might be serve as a light
source emitting light into surrounding tissue, and the second and
third fibers might be two detector fibers collecting reflected
light.
[0023] The invention might also be related to a computer program
for the processing unit of the system according to the invention.
The computer program is preferably loaded into a working memory of
a data processor. However, the computer program may also be
presented over a network like the worldwide web and can be
downloaded into the working memory of a data processor from such a
network. The computer program might control the emitting of light,
might process the signals coming from the light detector at the
proximal end of the detector fiber(s). These data might then be
visualized at a monitor.
[0024] It has to be noted that embodiments of the invention are
described with reference to different subject matters. In
particular, some embodiments are described with reference to
application steps whereas other embodiments are described with
reference to devices or systems. However, a person skilled in the
art will gather from the above and the following description that,
unless other notified, in addition to any combination of features
belonging to one type of subject matter also any combination
between features relating to different subject matters is
considered to be disclosed with this application.
[0025] The aspects defined above and further aspects, features and
advantages of the present invention can also be derived from the
examples of embodiments to be described hereinafter and are
explained with reference to examples of embodiments. The invention
will be described in more detail hereinafter with reference to
examples of embodiments but to which the invention is not
limited.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] FIG. 1 shows a cross section of the tip portion of a needle
according to a first embodiment of the invention.
[0027] FIG. 2 shows a front view of the needle according to the
first embodiment of the invention.
[0028] FIG. 3 shows a front view of a needle according to a second
embodiment of the invention.
[0029] FIG. 4 is an isometric illustration of a tip portion of a
needle according to the second embodiment of the invention.
[0030] FIG. 5 is a schematic illustration of a system according to
the invention, the system including a needle according to a third
embodiment of the invention.
[0031] The illustration in the drawings is schematically only and
not to scale. It is noted in different figures, same or similar
elements are provided with the same reference signs.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0032] FIG. 1 is a cross sectional view of the tip portion of a
needle according to a first embodiment of the invention. The needle
100 includes a shaft 110 having a longitudinal axis or centre axis
150. Parallel to the centre axis, there are formed two bores or
channels, in which fibers 130, 140 are located, respectively. These
fibers, namely the first fiber 130 and the second fiber 140,
include end surfaces 132, 142, respectively.
[0033] Further, the shaft 110 is cut at its distal end, such that a
bevel 120 is formed. The bevel 120 is a slanted surface which can
be divided in an area named as top 122 of the bevel, and an area
named as bottom 124 of the bevel. Further, the bevel 120 enclose an
angle b with the center axis of the shaft 110. The angle b is
preferably an acute angle of approximately 20.degree..
[0034] The end surface 132 of the first fiber 130 is located at the
top of the bevel and the end surface 142 of the second fiber 140 is
located at the bottom of the bevel. After positioning the ends of
the fibers in the channels or bores in the shaft, the bevel
together with the ends of the fibers might be polished. By way of
this, a smooth or even surface might be achieved including two end
surfaces of fibers, wherein such polished end surfaces provide for
good optical characteristics.
[0035] As further depict in FIG. 1, a distance A is defined, which
is measured from a middle of the end surface 132 of the first fiber
130 to the middle of the end surface 142 of the second fiber
140.
[0036] FIG. 2 is a front view of the needle according to the first
embodiment of the invention. FIG. 2 shows the bevel 120 together
with the end surface 132 of the first fiber and the end surface 142
of the second fiber. Furthermore, the usually circular cross
section of the shaft of the needle 100 defines a diameter D. The
distance A (see FIG. 1) is larger than the outer diameter D of the
needle, wherein A>1.1D or even A>1.25D, and preferably
A>1.5D.
With b as the tip angle of the bevel, the following equation might
count
A D > sin b + 0.1 sin b ( 1 ) ##EQU00002##
[0037] In the case of the first embodiment, in which the needle is
provided with a first fiber at the top of the bevel, and with a
second fiber at the bottom of the bevel, the first fiber might
serve as a light source emitting light into surrounding tissue, and
the second fiber might serve as a detector fiber collecting
reflected light.
[0038] FIG. 3 is a front view of a needle according to a second
embodiment of the invention. Generally, the second embodiment is
similar to the first embodiment. The second embodiment also
includes a shaft, a bevel forming an acute angle with the shaft, a
first fiber at the top of the bevel, and a second fiber at the
bottom of the bevel.
[0039] Additionally, the needle according to the second embodiment
comprises a third fiber with an end surface 252. The third fiber is
arranged in a channel or through bore which is formed parallel to
the centre axis of the shaft and, thus, parallel to the channels of
the first and second fibers. Further, the end surface 252 of the
third fiber is located in the vicinity of the end surface of the
second fiber, at the bottom 224 of the bevel 220.
[0040] In the case of the second embodiment, in which the needle is
provided with a first fiber at the top of the bevel, and with
second and third fibers at the bottom of the bevel, the first fiber
might serve as a light source emitting light into surrounding
tissue, and the second and third fibers might serve as detector
fibers collecting reflected light.
[0041] FIG. 4 shows the tip portion of the needle according to the
second embodiment as an isometric view. This view illustrates that
the actual shape of the surface of the bevel as well as of the end
surfaces of the fibers is substantially oval.
[0042] FIG. 5 illustrates a system according to the invention. The
system includes a needle 300 according to a third embodiment of the
invention. In this illustration, the needle 300 is an assembly of a
tip part 310, an inner tube 352, an outer tube 350, and a holder
part 360. Furthermore, two fibers 330 and 340 are shown in the
needle. An important part of the needle is the needle tip, in which
two or three bores are manufactured. In each bore a fiber is
mounted, by gluing. The tip is fixed to both inner tube and outer
tube by welding or gluing, wherein the inner and outer diameters of
the inner and the outer tube are adapted to correspond respective
structures at the proximal shaft section of the tip part. A space
356 between the tubes might be achieved, into which the through
bores in the tip part are open out. Coming out of the bores of the
tip part, the fibers 330, 340 are positioned in the hollow space
356 between both tubes.
[0043] The tip, fibers and both tubes, once assembled, are fixed to
a needle holder. Inside the holder the inner tube is connected with
a connector to which for instance a syringe or other tubing can be
fixed. In this way volumes of fluid can be dispensed through the
channel 354 of the inner tube and tip part, without interaction
with the fibers. The needle holder 360 also contains separate exit
362 for the fibers. After assembling tip, fibers, tubes and holder,
the bevel 320 of the needle (i.e. the needle tip) is polished to
obtain a proper surface quality for the fibers.
[0044] To have appropriate properties of the different parts of the
needle, the tip part might be made of a metal, an alloy or ceramic
material, and the shaft tubes might be made of a metal material,
wherein the metal material should be MRI compatible, for example
titanium.
[0045] Further, the system comprises a light source 332, a light
detector 242, a processing unit 370 and a monitor 380. The
processing unit 370 is capable of controlling the light source 332
to emit light into the fiber 330 such that light will be emitted
through the distal end surface of the fiber 330 at the top of the
bevel 320 into surrounding tissue. Depending on what kind of tissue
is in front of the bevel, more or less of the emitted light will be
reflected in the direction of the bottom of the bevel, to be
received be the other fiber 340. Through the fiber 340, the light
will is led to the light detector 342, which detector is adapted to
transform the light into electrical signals. These electrical
signals will be send by, for example, wire to the processing unit.
The processing unit will process the data corresponding to the
electrical signals, so that the processed data might be visualized
on a monitor 380. Based on said visualized data, it might be
possible to diagnose whether or not a tissue is cancerous.
[0046] In the following, exemplary needles according to the
invention will be described with respect to their outer diameter,
their insertion length, and their preferred use.
[0047] A biopsy needle might have an outer diameter of 1.27 mm up
to 2.108 mm, might be inserted into tissue with 100 mm to 150 mm of
its length, and might be used in soft tissue core biopsies in the
neck, the head, the breast, the prostate, and the liver.
[0048] A fine aspiration needle of soft tissue might have an outer
diameter between 0.711 mm and 2.108 mm, might be inserted into soft
tissue with 100 mm to 150 mm of its length, and might be used for
aspiration of soft tissue.
[0049] A brain biopsy needle might have an outer diameter of 2.108
mm, might be inserted into tissue with 150 mm up to 250 mm of its
length, and might be used for diagnostic brain biopsies.
[0050] A neuro puncture needle might have an outer diameter of 1.27
mm up to 2.108 mm, might be inserted into tissue with 150 mm to 200
mm of its length, wherein such needles allow a non-traumatic
approach to lesions in the brain.
[0051] An epidural needle might have an outer diameter between
0.711 mm and 1.473 mm, might be inserted into tissue with a length
of up to 150 mm, and might be used for treatments in the spinal
cord area such as steroid injections in the epidural space.
[0052] Finally, a needle electrode might have an outer diameter of
2 108 mm and smaller, might be inserted into tissue up to 250 mm of
its length, and might be used for radiofrequency ablation for
instance of tumors.
[0053] While the invention has been illustrated and described in
detail in the drawings and foregoing description, such illustration
and description are to be considered illustrative or exemplary and.
not restrictive; the invention is not limited to the disclosed
embodiments.
[0054] Other variations to the disclosed embodiments can be
understood and effected by those skilled in the art in practicing
the claimed invention, from a study of the drawings, the
disclosure, and the appended claims. In the claims, the word
"comprising" does not exclude other elements or steps, and the
indefinite article "a" or "an" does not exclude a plurality. A
processing unit may fulfill the functions of several items recited
in the claims. The mere fact that certain measures are recited in
mutually different dependent claims does not indicate that a
combination of these measures cannot be used to advantage. A
computer program may be stored/distributed on a suitable medium,
such as an optical storage medium or a solid-state medium supplied
together with or as part of other hardware, but may also be
distributed in other forms, such as via the Internet or other wired
or wireless telecommunication systems. Any reference signs in the
claims should not be construed as limiting the scope.
LIST OF REFERENCE SIGNS
[0055] 100, 200, 300 needle
[0056] 110, 210 shaft
[0057] 120, 220, 320 bevel
[0058] 122 top of the bevel
[0059] 124, 224 bottom of the bevel
[0060] 130, 330 first fiber
[0061] 132, 232 end surface of first fiber
[0062] 140, 340 second fiber
[0063] 142, 242 end surface of second fiber
[0064] 150 longitudinal axis of needle
[0065] 252 end surface of third fiber
[0066] 310 tip part
[0067] 332 light source
[0068] 342 light detector
[0069] 350 outer tube
[0070] 352 inner tube
[0071] 354 channel
[0072] 356 space between inner and outer tubes
[0073] 360 holder part
[0074] 362 opening
[0075] 370 processing unit
[0076] 380 monitor
* * * * *