U.S. patent application number 12/135968 was filed with the patent office on 2009-01-08 for surgical waveguide.
This patent application is currently assigned to Cynosure, Inc.. Invention is credited to James Henry Boll, Richard Shaun Welches.
Application Number | 20090012511 12/135968 |
Document ID | / |
Family ID | 40130073 |
Filed Date | 2009-01-08 |
United States Patent
Application |
20090012511 |
Kind Code |
A1 |
Welches; Richard Shaun ; et
al. |
January 8, 2009 |
SURGICAL WAVEGUIDE
Abstract
A surgical probe is disclosed which includes a stiff treatment
waveguide extending between a first end and a second end, the first
end being adapted for connection to a handpiece, the second end
being adapted for insertion through an incision into an area of
tissue. The treatment waveguide in configured to receive treatment
light from the handpiece at the first end, transmit the light to
the second end, and emit the light from the second end into a
portion of the tissue proximal the second end. The treatment
waveguide is adapted to penetrate through a portion of the area of
tissue in response to pressure applied to the handpiece.
Inventors: |
Welches; Richard Shaun;
(Manchester, NH) ; Boll; James Henry; (Newton,
MA) |
Correspondence
Address: |
FOLEY & LARDNER LLP
111 HUNTINGTON AVENUE, 26TH FLOOR
BOSTON
MA
02199-7610
US
|
Assignee: |
Cynosure, Inc.
|
Family ID: |
40130073 |
Appl. No.: |
12/135968 |
Filed: |
June 9, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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60933736 |
Jun 8, 2007 |
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60987617 |
Nov 13, 2007 |
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60987596 |
Nov 13, 2007 |
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60987821 |
Nov 14, 2007 |
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60987819 |
Nov 14, 2007 |
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61018729 |
Jan 3, 2008 |
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61018727 |
Jan 3, 2008 |
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Current U.S.
Class: |
606/15 ;
606/14 |
Current CPC
Class: |
A61B 18/201 20130101;
A61B 2017/00084 20130101; A61B 2018/00642 20130101; A61B 90/37
20160201; A61B 2018/00464 20130101; A61B 18/22 20130101; A61B
2017/00119 20130101; A61B 2018/00791 20130101; A61B 90/361
20160201; A61B 2218/007 20130101; A61B 2018/00166 20130101 |
Class at
Publication: |
606/15 ;
606/14 |
International
Class: |
A61B 18/22 20060101
A61B018/22 |
Claims
1. A surgical probe comprising: a stiff treatment waveguide
extending between a first end and a second end, said first end
being adapted for connection to a handpiece, said second end being
adapted for insertion through an incision into an area of tissue;
wherein said treatment waveguide in configured to receive treatment
light from the handpiece at the first end, transmit the light to
the second end, and emit the light from the second end into a
portion of the tissue proximal the second end; and wherein the
treatment waveguide is adapted to penetrate through a portion of
the area of tissue in response to pressure applied to the
handpiece.
2. The surgical probe of claim 1, wherein the treatment waveguide
is substantially free of external mechanical support.
3. The surgical probe of claim 2, wherein the treatment waveguide
is free from an external cannula.
4. The surgical probe of claim 3, wherein the treatment waveguide
comprises an optical fiber having a diameter of about 1000 .mu.m to
about 2000 .mu.m.
5. The surgical probe of claim 4, wherein the treatment waveguide
comprises one or more selected from the list of: glass, plastic,
and quartz.
6. The surgical probe of claim 3, wherein the sensing waveguide is
adapted to transmit treatment light at wavelengths of about 532 nm
to about 1550 nm.
7. The surgical probe of claim 3, wherein the second end of the
treatment waveguide comprises a strip and cleave tip.
8. The surgical probe of claim 3, wherein the second end of the
treatment waveguide comprises one selected from the group of: a
wedge shaped tip, an angled tip, or a side firing tip.
9. The surgical probe of claim 3, wherein said first end of the
treatment waveguide is adapted for detachable connection to the
handpiece.
10. The surgical probe of claim 9, further comprising the
handpiece, wherein the handpiece comprises one or more optical
elements adapted to direct light from a light source to the first
end of the treatment waveguide.
11. The surgical probe of claim 10, wherein the handpiece comprises
a sterile sheath defining an interior volume and an exterior
volume, wherein said one or more optical elements are positioned
within the interior volume and the treatment waveguide is
positioned in the exterior volume; and a connector adapted to
receive the first end of the treatment waveguide and to optically
couple first end of the treatment waveguide to the one or more
optical elements while preventing pneumatic communication between
the interior and exterior volumes.
12. The surgical probe of claim 3, wherein the treatment waveguide
is adapted to receive infrared light from an area of tissue
proximal the second end of the sensing waveguide, direct the
infrared light to the first end of the sensing waveguide, and emit
the infrared light onto a infrared temperature sensor located
within the handpiece.
13. The surgical probe of claim 3, further comprising a sensing
waveguide extending between a first end proximal the first end of
the treatment waveguide and a second end proximal the second end of
the treatment waveguide; wherein said waveguide is adapted to
receive infrared light from an area of tissue proximal the second
end of the sensing waveguide, direct the infrared light to the
first end of the sensing waveguide, and emit the infrared light
onto a infrared temperature sensor located within the
handpiece.
14. The surgical probe of claim 13, wherein the sensing waveguide
is coaxial with the treatment waveguide.
15. The surgical probe of claim 13, wherein the sensing waveguide
comprises an optical fiber positioned beside the treatment
waveguide.
16. The surgical probe of claim 15, wherein the sensing waveguide
is relatively less stiff than the treatment waveguide, and further
comprising an overjacket surrounding the treatment waveguide and
the sensing waveguide adapted to secure the treatment waveguide and
the sensing waveguide in fixed relative position.
17. The surgical probe of claim 13, wherein the sensing waveguide
is adapted to transmit light at wavelengths of about 5 .mu.m to
about 14 .mu.m.
18. The surgical probe of claim 13, wherein the treatment waveguide
comprises ZnSe.
19. The surgical probe of claim 13, further comprising: the
handpiece; the temperature sensor; and a processor, wherein the
temperature sensor is configured to detect one or more properties
of the infrared light from the first end of the sensing waveguide,
and wherein the processor is configure to determine information
indicative of the temperature of the tissue area of tissue proximal
the second end of the sensing waveguide based on the one or more
detected properties of the light.
20. The surgical probe of claim 19. further comprising the an
optical element configured to separate a first portion of the
infrared light at a first wavelength and a second portion of the
infrared light at a second wavelength; wherein the temperature
sensor is configured to detect a property of the first portion and
a property of the second portion; and wherein the processor is
configured to determine information indicative of the temperature
of the area of tissue proximal the second end of the sensing
waveguide based on the property of the first portion and the
property of the second portion.
21. The surgical probe of claim 20, wherein the processor is
configured to determine information indicative of the temperature
of the tissue area of tissue proximal the second end of the sensing
waveguide based on the property of the first portion and the
property of the second portion by comparing the properties.
22. The surgical probe of claim 19, wherein the processor is
configured to control the treatment light based on the determined
information indicative of the temperature of the area of
tissue.
23. A method comprising: providing a stiff treatment waveguide
extending between a first end and a second end, said first end
connected to a handpiece, said second end being adapted for
insertion through an incision into an area of tissue, said
treatment waveguide being substantially free of external mechanical
support; inserting said waveguide into an incision in a patient;
applying pressure to the handpiece to advancing said waveguide
through an area of tissue; providing treatment light directed from
a treatment source to the handpiece directing treatment light to
the first end of the treatment waveguide, transmitting the light
from the first end to the second end, emitting the light from the
second end into a portion of tissue proximal the second end.
24. The method of claim 23, wherein the treatment waveguide is free
from an external cannula.
25. The method of claim 24, further comprising: repetitively
advancing and withdrawing the treatment waveguide along multiple
paths through the area of tissue; applying treatment light to
multiple areas of tissue along the multiple paths.
26. The method of claim 25, further comprising: providing sensing
waveguide extending between a first end proximal the first end of
the treatment waveguide and a second end proximal the second end of
the treatment waveguide, receiving infrared light from an area of
tissue proximal the second end of the sensing waveguide; directing
the infrared light to the first end of the sensing waveguide,
emitting the infrared light onto a infrared temperature sensor
located within the handpiece; using the temperature sensor,
detecting one or more properties of the infrared light from the
first end of the sensing waveguide, and determine information
indicative of the temperature of the tissue area of tissue proximal
the second end of the sensing waveguide based on the one or more
detected properties of the light.
27. The method of claim 26, further comprising, controlling
application of the treatment light based on the determined
information indicative of the temperature of the area of tissue.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims benefit to each of U.S.
Provisional Application Ser. No. 60/987,596, filed Nov. 13, 2007,
U.S. Provisional Application Ser. No. 60/987,617, filed Nov. 13,
2007, U.S. Provisional Application Ser. No. 60/987,819, filed Nov.
14, 2007, U.S. Provisional Application Ser. No. 60/987,821, filed
Nov. 14, 2007, U.S. Provisional Application Ser. No. 61/018,727,
filed Jan. 3, 2008, U.S. Provisional Application Ser. No.
61/018,729, filed Jan. 3, 2008, and U.S. Provisional Application
Ser. No. 60/933,736, filed Jun. 8, 2007, the contents each of which
are incorporated by reference herein in their entirety.
BACKGROUND
[0002] The present invention relates to a surgical waveguide.
Plastic surgeons, dermatologists, and their patients continually
search for new and improved methods for treating the effects of an
aging or otherwise damaged skin. One common procedure for
rejuvenating the appearance of aged or photodamaged skin is laser
skin resurfacing using a carbon dioxide laser. Another technique is
non-ablative laser skin tightening, which does not take the top
layer of skin off, but instead uses a deep-penetrating laser to
treat the layers of skin beneath the outer epidermal layer,
tightening the skin and reducing wrinkles to provide a more
youthful appearance.
[0003] For such techniques as laser skin tightening treatment, it
has been difficult to control the depth and amount of energy
delivered to the collagen without also damaging or killing the
dermal cells. Much of the energy of the treatment pulse is wasted
due to scattering and absorption in the outer epidermal layer, and
the relatively high pulse energy required to penetrate this outer
layer can cause pain and epidermal damage.
[0004] Some skin tightening techniques include using a hollow
tubular cannula that contains an optical fiber connected to a laser
source. The cannula can be inserted subcutaneously into a patient
so that the end of the fiber is located within the tissue
underlying the dermis. The source emits a treatment output, for
example an output pulse that is conveyed by the fiber to the
dermis, which causes collagen shrinkage within the treatment area,
thus tightening the skin.
[0005] A technical complication common to the use of cannula
sheathed optical fibers for surgical applications is the break off
of fatigued fiber ends (`tips`). Additionally, an improperly
tightened optical fiber can slide up into the cannula such that the
fiber tip is located within the cannula air space. This can cause
very high cannula and fiber tip temperatures with corresponding
excessive temperatures coupled to adjacent tissue. The
susceptibility of standard optical fibers to tip breakage is
worsened by autoclave cycles and by long duration high power
use.
SUMMARY OF THE INVENTION
[0006] In one aspect, the inventors have realized that a surgery
tool employing a robust waveguide can be used in an invasive laser
surgical procedure. Use of such a waveguide can eliminate the need
for a cannula, as the waveguide may be inserted directly into the
incision. This improves both safety and efficacy in that broken and
lost optical fiber tips are avoided. Further, this reduces or
eliminates the possibility of the waveguide slipping up into a
cannula or catheter and operating within an air filled space in the
cannula or catheter, leading to excessive waveguide tip temperature
rise.
[0007] In another aspect, the inventors have realized that
including infrared (IR) temperature sensing with a laser surgical
device of the type described above, or otherwise, allows for
temperature monitoring of a treatment area. Temperature information
can be used as a feedback to control the applied treatment.
[0008] In some embodiments, a surgery tool or a surgical probe
includes a stiff treatment waveguide extending between a first end
and a second end, the first end being adapted for connection to a
handpiece, and the second end being adapted for insertion through
an incision into an area of tissue. In some embodiments, the
treatment waveguide is configured to receive treatment light from
the handpiece at the first end, transmit the light to the second
end, and emit the light from the second end into a portion of the
tissue proximal the second end.
[0009] In some embodiments, the treatment waveguide is adapted to
penetrate through a portion of the area of tissue in response to
pressure applied to the handpiece. In some embodiments, the
treatment waveguide is substantially free of external mechanical
support. The treatment waveguide is free from an external
cannula.
[0010] In some embodiments, the treatment waveguide includes an
optical fiber having a diameter of about 1000 .mu.m to about 2000
.mu.m. The treatment waveguide may be composed of one or more
materials selected from the list of: glass, plastic, quartz, and Nd
glass, and a Cerium-doped quartz. A treatment waveguide composed of
a glass may be sheathed in a plastic coating to prevent fragments
and shards from an accidental break from contaminating a treatment
site.
[0011] In some embodiments, the surgical probe of the sensing
waveguide is adapted to transmit treatment light at wavelengths of
about 532 nm to about 1550 nm. The second end of the treatment
waveguide comprises a strip and cleave tip. The second end of the
treatment waveguide comprises one selected from the group of: a
wedge shaped tip, an angled tip, or a side firing tip.
[0012] In some embodiments, the first end of the treatment
waveguide is adapted for detachable connection to the handpiece. In
some embodiments, the handpiece itself includes one or more optical
elements adapted to direct light from a light source to the first
end of the treatment waveguide. The handpiece may further include:
a sterile sheath defining an interior volume and an exterior
volume, where the one or more optical elements are positioned
within the interior volume and the treatment waveguide is
positioned in the exterior volume, and a connector adapted to
receive the first end of the treatment waveguide and to optically
couple first end of the treatment waveguide to the one or more
optical elements while preventing pneumatic communication between
the interior and exterior volumes.
[0013] In some embodiments, the treatment waveguide is adapted to
receive infrared light from an area of tissue proximal the second
end of the sensing waveguide, direct the infrared light to the
first end of the sensing waveguide, and emit the infrared light
onto a infrared temperature sensor located within the
handpiece.
[0014] In some embodiments, the surgical probe further includes a
sensing waveguide extending between a first end proximal the first
end of the treatment waveguide and a second end proximal the second
end of the treatment waveguide, where the waveguide is adapted to
receive infrared light from an area of tissue proximal the second
end of the sensing waveguide, direct the infrared light to the
first end of the sensing waveguide, and emit the infrared light
onto a infrared temperature sensor located within the
handpiece.
[0015] In some embodiments, the surgical probe sensing waveguide is
coaxial with the treatment waveguide. In some embodiments, the
sensing waveguide comprises an optical fiber positioned beside the
treatment waveguide. In some embodiments, the sensing waveguide is
relatively less stiff than the treatment waveguide, and further
includes an overjacket surrounding the treatment waveguide and the
sensing waveguide adapted to secure the treatment waveguide and the
sensing waveguide in fixed relative position. The sensing waveguide
is adapted to transmit light at wavelengths of about 5 .mu.m to
about 14 .mu.m. The treatment waveguide may be composed of
ZnSe.
[0016] In some embodiments, the surgical probe further includes:
the handpiece, the temperature sensor, and a processor, where the
temperature sensor is configured to detect one or more properties
of the infrared light from the first end of the sensing waveguide,
and where the processor is configured to determine information
indicative of the temperature of the tissue area of tissue proximal
the second end of the sensing waveguide based on the one or more
detected properties of the light.
[0017] In some embodiments, the surgical probe further includes an
optical element configured to separate a first portion of the
infrared light at a first wavelength and a second portion of the
infrared light at a second wavelength, where the temperature sensor
is configured to detect a property of the first portion and a
property of the second portion, and the processor is configured to
determine information indicative of the temperature of the area of
tissue proximal the second end of the sensing waveguide based on
the property of the first portion and the property of the second
portion.
[0018] In some embodiments, the processor is configured to
determine information indicative of the temperature of the tissue
area of tissue proximal the second end of the sensing waveguide
based on the property of the first portion and the property of the
second portion by comparing the properties. In some embodiments,
the processor is configured to control the treatment light based on
the determined information indicative of the temperature of the
area of tissue.
[0019] In some embodiments, a method is defined including:
providing a stiff treatment waveguide extending between a first end
and a second end, the first end connected to a handpiece, the
second end being adapted for insertion through an incision into an
area of tissue, where the treatment waveguide being substantially
free of external mechanical support. The method further includes:
inserting said waveguide into an incision in a patient, applying
pressure to the handpiece to advancing said waveguide through an
area of tissue, providing treatment light directed from a treatment
source to the handpiece, directing treatment light to the first end
of the treatment waveguide, transmitting the light from the first
end to the second end, and emitting the light from the second end
into a portion of tissue proximal the second end.
[0020] In some embodiments, the method may specify the treatment
waveguide is free from an external cannula. The method further may
include: repetitively advancing and withdrawing the treatment
waveguide along multiple paths through the area of tissue and
applying treatment light to multiple areas of tissue along the
multiple paths. The method may further include: providing a sensing
waveguide extending between a first end proximal the first end of
the treatment waveguide and a second end proximal the second end of
the treatment waveguide, receiving infrared light from an area of
tissue proximal the second end of the sensing waveguide, directing
the infrared light to the first end of the sensing waveguide, and
emitting the infrared light onto a infrared temperature sensor
located within the hand piece.
[0021] In some embodiments, using the temperature sensor, the
method may further specify detecting one or more properties of the
infrared light from the first end of the sensing waveguide and
determining information indicative of the temperature of the tissue
area of tissue proximal the second end of the sensing waveguide
based on the one or more detected properties of the light. In some
embodiments, the method further includes controlling application of
the treatment light based on the determined information indicative
of the temperature of the area of tissue.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The foregoing and other objects, features and advantages of
the invention will be apparent from the following more particular
description, as illustrated in the accompanying drawings in which
like reference characters refer to the same parts throughout the
different views. The drawings are not necessarily to scale,
emphasis instead being placed upon illustrating the principles of
the invention.
[0023] FIG. 1 shows a first view of a surgical waveguide
[0024] FIG. 2 shows a second view of a surgical waveguide.
[0025] FIG. 3 shows an partial assembly drawing of a surgical
waveguide.
[0026] FIG. 4 shows an assembly drawing of a connection between the
surgical waveguide and an optics focus interface to a fiber optic
line.
[0027] FIG. 5 shows a collection of surgical waveguide tips
designs.
[0028] FIG. 6 shows a surgical waveguide integrated with a thermal
temperature sensor.
[0029] FIG. 7 shows a cross sectional view of the optics focus
interface between the surgical waveguide and a fiber optic
line.
[0030] FIG. 8 shows a plot of radiation transmission vs. wavelength
for a ZnSe sense fiber with an anti-reflection (AR) coating.
DETAILED DESCRIPTION
[0031] FIGS. 1 and 2 show a first and a second view of a surgical
waveguide adapted for use in a subdermal tissue ablation procedure
according to an embodiment. FIGS. 1 and 2 show a laser surgical
waveguide assembly 100 including a hand piece 105 which receives a
surgical waveguide 110. The surgical waveguide 110 is chosen to
have suitable mechanical, material, and optical properties for
surgical applications without need for a supporting cannula. That
is, the surgical waveguide 110 itself may be inserted through an
incision directly into a patient's tissue for the delivery of
therapeutic laser light. For example, the waveguide may be chosen
to be mechanically strong and/or stiff enough to withstand multiple
aggressive passes into fibrous tissue, while being capable of
transmitting high power laser pulses. Further, the waveguide may be
chosen to be mechanically strong and/or stiff enough to maintain
control of a surgical waveguide 110 tip, such that the surgical
waveguide 110 body undergoes a minimum of flexure under a
compressive or shear force applied by the hand piece 105. In some
embodiments, the waveguide may be removable, disposable, and/or
consumable
[0032] For example, in some embodiments, the surgical waveguide 110
can be a relatively short (e.g., about 6'' or less) length of large
core fiber having a large diameter (e.g. about 1000 .mu.m or more,
about 1000-2000 .mu.m, or greater than 2000 .mu.m. The cost for
such a fiber is low due to the short fiber length, but due to its
large diameter, the fiber has sufficient mechanical strength to
meet the requirements of surgical applications. The larger diameter
of the fiber at the fiber tip lowers the power density at the tip
and may add to the longevity of the fiber tip. In some embodiments,
the surgical waveguide is a consumable, large diameter, (e.g., 1800
.mu.m) optical fiber with a strip and cleave tip. In such
embodiments, as the tip of the fiber becomes worn with use, it may
be removed, and the exposed fiber end may be cleaved to provide a
new operating tip.
[0033] In some embodiments, the surgical waveguide 110 comprises a
stiff glass or plastic waveguide suitable for surgical applications
without the need for a cannula. Other suitable waveguide materials
include glass or quartz rods with some sort of cladding, hollow
tubing with dielectric coatings, Nd glass, and Cerium-doped quartz.
In some embodiments, waveguides made of glass are sheathed in a
plastic coating analogous to a safety glass to retain glass
fragments and shards within the plastic coating if the glass
breaks, and greatly reducing the possibility of glass fragments and
shards contaminating a treatment site. In various embodiments, the
surgical waveguide 110 requires a cladding material. The cladding
material may be selected to add necessary strength and stiffness to
the surgical waveguide 110, eliminating the need for cannula.
Although several examples of waveguide types have been provided, it
is to be understood by those skilled in the art that any other
suitable material or configuration may be used.
[0034] Referring again to FIG. 1, the surgical waveguide 110 is
held in place in the hand piece 105 by a waveguide chuck 115. The
surgical waveguide 110 protrudes from the back end of the hand
piece 105 and is received by a waveguide stop 120. A treatment
laser light from a treatment laser 450 is coupled to a reusable
optical fiber 125 which terminates in a connector 130, for example,
an SMA-like connector, which receives the hand piece 105.
[0035] Light from the reusable optical fiber 125 is coupled into
the surgical waveguide 110 using a focusing assembly 135 including,
for example, a set of optical elements 140. The set of optical
elements 140 includes, for example, lenses, a single or dual focus
mirror, and others. The set of optical elements 140 directs light
from the end of the reusable fiber 125 into the surgical waveguide
110. In some embodiments, an optical coupling can be achieved by
placing the end faces of the reusable fiber 125 and the surgical
waveguide 110 in contact or close proximity, a technique known as
`butt-splicing`. Note that, because the reusable fiber 125 is not
inserted into the patient, the reusable fiber 125 need not be as
physically strong as the surgical waveguide 110. For example, in
some embodiments, the reusable fiber may be a 300-600 .mu.m
fiber.
[0036] The surgical waveguide 110 and hand piece 105 may be
sterilized using, for example, an autoclave. The reusable fiber
125, connector 130, and focusing assembly 135 are covered with a
sterile sheath 150, and thus need not be autoclaved. Note that this
allows for the use of, for example, a focusing assembly 135
including optical elements 140 that are not sufficiently robust to
undergo one or more autoclave cycles.
[0037] FIG. 3 shows a partial assembly drawing of a surgical
waveguide adapted for use in a subdermal tissue ablation procedure
according to an embodiment. FIG. 4 shows an assembly drawing of a
connection between the surgical waveguide and an optics focus
interface to a fiber optic line according to an embodiment. When
connected, the surgical waveguide 110 pierces through the sterile
sheath 150. The sterile sheath 150 is clamped between the hand
piece 110 and the connector 130, thereby maintaining the integrity
of the sheath. For example, in some embodiments the hand piece 110
may include a coupling with an O-ring groove 305. The connector 130
and focus assembly 135 may include a matching O-ring 310. When
connected, the O-ring 310 compresses the sterile sheath 150 against
the hand piece 110 O-ring groove 305, preventing communication
between the sterile region inside the sterile sheath 150 and the
non-sterile region outside of the sterile sheath 150.
[0038] FIG. 5 shows a collection of surgical waveguide tips designs
according to an embodiment. FIG. 5 shows several embodiments of
surgical waveguides, including a glass waveguide 505, a consumable
optical fiber 510 with strip and cleave end as described above, a
hollow metal waveguide 515, and a quartz waveguide 520. A
collection of waveguide tips with different exemplary
configurations are shown, whereby arrows indicate the direction of
light emission. The collection of waveguide tips includes: wedge
tips 550, angled tips 555, and side-firing tips 560. In some
embodiments, the surgical waveguide 110 may be discarded after each
use. In some embodiments, the surgical waveguide 110 may be reused
multiple times, for example, being sterilized by autoclave between
each use. In some embodiments, the surgical waveguide 110 may be
discarded after a given number of uses, duration of use, duration
of use at a given power level, etc.
[0039] FIG. 6 shows the surgical waveguide integrated with an IR
temperature sensor adjacent to the treatment waveguide fiber tip.
FIG. 7 shows a cross sectional view of the optics focus interface
between the surgical waveguide and a fiber optic line. An IR
waveguide 605, for example a ZnSe sense fiber, is bundled with the
surgical waveguide 110 in an over-jacket 610. In the example shown,
a two sensor IR photodetector assembly 615 is located in the hand
piece 105 adjacent to the treatment beam focus assembly 135.
Portions of light from the IR waveguide 605 at two distinct
wavelengths are separated and directed respectively to the two IR
sensors 620 using, for example, a dichroic beamsplitter 621.
Signals from the two IR sensors 620 are compared differentially to
increase sensitivity and reject errors due to a sense waveguide 605
transmission loss variables or characteristics.
[0040] The signals from the two IR sensors 620 are processed to
obtain temperature information about a tissue under treatment. IR
temperature monitoring provides a tissue temperature feedback to
the treatment laser 450, which may use the tissue temperature
feedback to adjust laser energy deposition based on observed tissue
temperatures. In various embodiments, adjusting laser energy
deposition could include a simple maximum temperature safety limit,
or the tissue temperature feedback could allow for a closed loop
tissue temperature control. In either case, the treatment laser 450
takes feedback from the IR sense fiber 605, or equivalently, from
an IR sense fiber ring 705, then adjusts the treatment laser 450
output power in a closed loop to achieve a selected tissue
temperature.
[0041] In some embodiments, the surgical waveguide itself can
collect IR light from the treatment area during treatment to
provide IR tissue temperature sensing. However, for some
applications, such a waveguide or fiber would be required to pass
high energy treatment laser 450 wavelengths in the range of
approximately 532 to 1550 nm and also to pass IR wavelengths on the
order of 5-14 .mu.m for temperature sensing and feedback. In some
embodiments, this may be an unwanted requirement. Referring back to
FIG. 6 shows an example of a device which avoids this requirement
by employing a dual fiber approach.
[0042] As with the systems described above, light at a treatment
wavelength is delivered via a surgical waveguide 110, for example,
a stiffened fiber suitable for surgical use without a cannula. As
shown in FIG. 7, the surgical waveguide 110 is surrounded by and
coaxial with an IR waveguide tube 710, as an example, a ZnSe sense
fiber cylinder or tube. As described above, the surgical waveguide
110 is coupled to a treatment fiber 125 which delivers light from a
treatment source, in the given example, a treatment laser 450
source. The coupling is accomplished using a focus assembly 135 in
a connector 130 connected to the back of the hand piece 105. As
shown in FIG. 7, the connector 130 also includes an IR pass filter
ring 715 to filter out stray treatment laser 450 light and an IR
sense fiber ring 705, as an example, an annular array of IR
photodetectors, aligned with the IR waveguide tube 710. The IR
sense fiber ring 705 produces electrical signals in response to
incident IR radiation. The electrical signals corresponding to IR
radiation incident to the IR sense fiber ring 705 are directed to a
processor 706, which functions to determine the tissue temperature
and to provide a feedback to the treatment laser 450, as described
above.
[0043] As described above, in various embodiments, IR radiation
from a treatment site is propagated to an IR photodetector assembly
615 through the IR pass filter ring 715 via the IR sense fiber ring
705 and IR waveguide tube 710, or via other suitable optics. Other
optics suitable to function as the IR waveguide tube 710 may
include, for example, anti-reflection (AR) coated ZnSe or Germanium
rods or tubes, or certain IR transmissive plastics, or even
photonic waveguides. FIG. 8 shows a plot of radiation transmission
vs. wavelength 800 for a ZnSe sense fiber with an anti-reflection
(AR) coating as implemented.
[0044] Although several examples of IR optics and geometries are
presented, it is to be understood that other suitable materials,
geometries, and configurations may be used.
[0045] While this invention has been particularly shown and
described with references to example embodiments thereof, it will
be understood by those skilled in the art that various changes in
form and details may be made therein without departing from the
scope of the invention.
[0046] For example, it is to be understood that although in the
examples provided above laser light is used for treatment, other
sources of treatment light (e.g. flash lamps, light emitting
diodes) may be used.
[0047] In some embodiments, a safety accelerometer 160 may be
incorporated in the laser surgical waveguide assembly 100. For
example, as shown in FIGS. 1 and 2, an accelerometer 160 may by
included within the sterile sheath 150 and attached to, for
example, the connector 130 or focus assembly 135. The accelerometer
160 may be attached to, for example, an electronic processor 706
via wiring 161 contained in the sterile sheath 150. During
treatment, the accelerometer 160 measures acceleration of the hand
piece 105 and may determine, for example, if the hand piece 105 has
come to rest in a single position for too long a period of time,
potentially leading to unsafe heating levels, triggering, for
example, a warning, or treatment laser 450 shut off.
[0048] In various embodiments, other safety devices (e.g. position
sensors, temperature sensors, etc.) may similarly be incorporated
with the surgical waveguide 110 and hand piece 105.
[0049] One or more or any part thereof of the treatment, IR
sensing, or safety techniques described above can be implemented in
computer hardware or software, or a combination of both. The
methods can be implemented in computer programs using standard
programming techniques following the method and figures described
herein. Program code is applied to input data to perform the
functions described herein and generate output information. The
output information is applied to one or more output devices such as
a display monitor. Each program may be implemented in a high level
procedural or object oriented programming language to communicate
with a computer system. However, the programs can be implemented in
assembly or machine language, if desired. In any case, the language
can be a compiled or interpreted language. Moreover, the program
can run on dedicated integrated circuits preprogrammed for that
purpose.
[0050] Each such computer program is preferably stored on a storage
medium or device (e.g., ROM or magnetic diskette) readable by a
general or special purpose programmable computer, for configuring
and operating the computer when the storage media or device is read
by the computer to perform the procedures described herein. The
computer program can also reside in cache or main memory during
program execution. The analysis method can also be implemented as a
computer-readable storage medium, configured with a computer
program, where the storage medium so configured causes a computer
to operate in a specific and predefined manner to perform the
functions described herein.
[0051] As used herein the term "light" is to be understood to
include electromagnetic radiation both within and outside of the
visible spectrum, including, for example, ultraviolet and infrared
radiation.
[0052] While the invention has been described in connection with
the specific embodiments thereof, it will be understood that it is
capable of further modification. Furthermore, this application is
intended to cover any variations, uses, or adaptations of the
invention, including such departures from the present disclosure as
come within known or customary practice in the art to which the
invention pertains, and as fall within the scope of the appended
claims.
[0053] It should be appreciated that the particular implementations
shown and described herein are examples and are not intended to
otherwise limit the scope in any way.
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