U.S. patent application number 17/734162 was filed with the patent office on 2022-09-15 for apparatus for subretinal administration of therapeutic agent via a curved needle.
The applicant listed for this patent is Gyroscope Therapeutics Limited. Invention is credited to Michael F. Keane, Isaac J. Khan, Benjamin L. Ko, Thomas E. Meyer, Brendan J. Oberkircher, Daniel W. Price.
Application Number | 20220288306 17/734162 |
Document ID | / |
Family ID | 1000006303555 |
Filed Date | 2022-09-15 |
United States Patent
Application |
20220288306 |
Kind Code |
A1 |
Meyer; Thomas E. ; et
al. |
September 15, 2022 |
APPARATUS FOR SUBRETINAL ADMINISTRATION OF THERAPEUTIC AGENT VIA A
CURVED NEEDLE
Abstract
An apparatus includes a body, a cannula, and a needle. The
cannula is flexible and extends distally from the body. The needle
is slidably disposed in the cannula. The needle includes a sharp
distal tip and a curved portion. The needle is configured to
translate relative to the cannula between a proximal position and a
distal position. The distal tip is configured to be positioned
inside the cannula when the needle is in the proximal position. The
distal tip is configured to be positioned outside the cannula when
the needle is in the distal position. The needle is resiliently
biased to extend along a curve through the curved portion.
Inventors: |
Meyer; Thomas E.;
(Philadelphia, PA) ; Ko; Benjamin L.; (Cincinnati,
OH) ; Khan; Isaac J.; (Bridgewater, NJ) ;
Price; Daniel W.; (Loveland, OH) ; Oberkircher;
Brendan J.; (Cincinnati, OH) ; Keane; Michael F.;
(Downingtown, PA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Gyroscope Therapeutics Limited |
London |
|
GB |
|
|
Family ID: |
1000006303555 |
Appl. No.: |
17/734162 |
Filed: |
May 2, 2022 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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16599206 |
Oct 11, 2019 |
11338084 |
|
|
17734162 |
|
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|
15438918 |
Feb 22, 2017 |
10478553 |
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16599206 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61F 9/0008 20130101;
A61M 5/168 20130101; A61M 5/329 20130101; A61F 9/0026 20130101;
A61M 5/158 20130101; A61F 9/0017 20130101; A61M 2205/582 20130101;
A61M 2210/0612 20130101; A61M 2005/1585 20130101 |
International
Class: |
A61M 5/158 20060101
A61M005/158; A61F 9/00 20060101 A61F009/00; A61M 5/168 20060101
A61M005/168 |
Claims
1-20. (canceled)
21. An apparatus, comprising: (a) a body; (b) a cannula extending
distally from the body, wherein the cannula is flexible, wherein
the cannula is sized and configured to advance between a sclera and
a choroid of a patient's eye; and (c) a needle slidably disposed in
the cannula, wherein the needle includes: (i) a sharp distal tip,
wherein the needle is configured to translate relative to the
cannula between a proximal position and a distal position, wherein
the distal tip is configured to be positioned inside the cannula
when the needle is in the proximal position and wherein the distal
tip is configured to be positioned outside the cannula when the
needle is in the distal position, (ii) a curved portion, wherein
the needle is resiliently biased to extend along a curve through
the curved portion, and (iii) a straight distal portion extending
along an exit axis, the straight distal portion extending between
the curved portion and the sharp distal tip, wherein the needle is
resiliently biased to extend along a straight path along the
straight distal portion.
22. The apparatus of claim 21, wherein the cannula includes an
opening.
23. The apparatus of claim 22, wherein the opening faces
distally.
24. The apparatus of claim 21, wherein the curved portion is
resiliently biased to define a constant radius of curvature.
25. The apparatus of claim 24, wherein the radius of curvature is
between approximately 7 mm and approximately 12 mm.
26. The apparatus of claim 24, wherein the radius of curvature is
between approximately 4 mm and approximately 15 mm.
27. The apparatus of claim 24, wherein the radius of curvature is
between approximately 9 mm and approximately 10 mm.
28. The apparatus of claim 21, wherein the curved portion is
configured to position the distal tip at a progressively increasing
exit angle relative to a longitudinal axis of the cannula based on
a distance to which the needle is advanced distally relative to the
cannula.
29. The apparatus of claim 21, wherein the curved portion comprises
a first curved region and a second curved region, wherein the first
curved region is located near a distal portion of the needle and
wherein the second curved region is located proximal to the first
curved region.
30. The apparatus of claim 21, wherein the needle further includes
a straight proximal portion, wherein the curved portion is
longitudinally positioned between the straight proximal portion and
the straight distal portion.
31. The apparatus of claim 21, wherein the cannula is flexible
enough to conform to structures and contours of the patient's eye
yet the cannula has sufficient column strength to permit
advancement of the cannula between the sclera and the choroid of
the patient's eye without buckling.
32. The apparatus of claim 21, wherein the exit axis extends
distally from the cannula at an exit angle of approximately 7
degrees to approximately 9 degrees relative to a longitudinal axis
of the cannula, wherein the exit angle is configured to deflect the
needle in a direction to ensure penetration of the needle into the
choroid of the patient's eye and to minimize the possibility of the
needle continuing beneath the choroid of the patient's eye through
a suprachoroidal space of the patient's eye.
33. An apparatus, comprising: (a) a body; (b) a cannula extending
distally from the body, wherein the cannula is flexible, wherein
the cannula is sized and configured to advance between a sclera and
a choroid of a patient's eye, wherein the cannula has a generally
rectangular cross-sectional shape that is configured to prevent the
cannula from rotating as the cannula is inserted into the patient's
eye, wherein the cannula includes: (i) opposing inner and outer
surfaces, (ii) a distal end, (iii) an opening, and (iv) a needle
guide that is coupled with the inner surface of the cannula,
wherein the needle guide is made from a different material from the
cannula, wherein the needle guide does not extend into the opening;
and (c) a needle slidably disposed in the cannula, wherein the
generally rectangular cross-sectional shape of the cannula is
configured to ensure that the needle exits from the opening of the
cannula in a predictable direction, wherein the needle is
configured to extend through a lumen of the needle guide, wherein
the needle includes: (i) a sharp distal tip, wherein the needle is
configured to translate relative to the cannula between a proximal
position and a distal position, wherein the distal tip is
configured to be positioned inside the cannula when the needle is
in the proximal position and wherein the distal tip is configured
to extend past the opening when the needle is in the distal
position, and (ii) a curved portion, wherein the curved portion is
configured to provide an oblique exit angle to a portion of the
needle extending past the opening when the needle is in the distal
position.
34. The apparatus of claim 33, wherein the curved portion is
resiliently biased to assume a curved configuration, wherein the
curved portion is further configured to deform to a substantially
straight configuration within the cannula when the needle is in the
proximal position.
35. The apparatus of claim 34, wherein the curved portion is
resiliently biased to define a radius of curvature, wherein the
radius of curvature is between 9 mm and 11 mm when the curved
portion is disposed outside of the cannula.
36. The apparatus of claim 33, wherein the opening is located
between the opposing inner and outer surfaces, wherein the opening
defines a perimeter that increases moving outwardly from the inner
surface to the outer surface of the cannula which is configured to
achieve a broader range of exit angles based on the extent to which
the needle is advanced distally.
37. The apparatus of claim 33, wherein the needle is selected from
the group consisting of between 27 gauge and 45 gauge needles,
wherein the size of the needle is configured to allow the needle to
penetrate through the choroid of the patient's eye and to be
removed such that the choroid of the patient's eye is
self-sealing.
38. An apparatus, comprising: (a) a body; (b) a cannula extending
distally from the body, wherein the cannula is flexible, wherein
the cannula is sized and configured to advance between a sclera and
a choroid of a patient's eye; (c) a needle slidably disposed in the
cannula, wherein the needle includes: (i) a sharp distal tip,
wherein the needle is configured to translate relative to the
cannula between a proximal position and a distal position, wherein
the distal tip is configured to be positioned inside the cannula
when the needle is in the proximal position and wherein the distal
tip is configured to be positioned outside the cannula when the
needle is in the distal position, and (ii) a curved portion,
wherein the needle is resiliently biased to extend along a curve
through the curved portion, wherein the curved portion is
resiliently biased to define a constant radius of curvature; and
(d) an actuator configured to distally advance the needle relative
to the cannula to position the needle at a predetermined location
within the patient's eye.
39. The apparatus of claim 38, wherein the needle is a stainless
steel hypodermic needle that is sized and configured to deliver a
therapeutic agent while being small enough to minimize incidental
trauma as the stainless steel hypodermic needle penetrates tissue
structures of the patient's eye.
40. The apparatus of claim 38, wherein the cannula includes a
distal end that is configured to provide separation between the
sclera and the choroid of the patient's eye to enable the cannula
to be advanced between the sclera and the choroid of the patient's
eye while not inflicting trauma to either the sclera or the choroid
of the patient's eye.
Description
PRIORITY
[0001] This application claims priority to U.S. Provisional Patent
Application No. 62/305,767, entitled "Curved Needle Choroidal
Penetration," filed Mar. 9, 2016, the disclosure of which is
incorporated by reference herein.
BACKGROUND
[0002] The human eye comprises several layers. The white outer
layer is the sclera, which surrounds the choroid layer. The retina
is interior to the choroid layer. The sclera contains collagen and
elastic fiber, providing protection to the choroid and retina. The
choroid layer includes vasculature providing oxygen and nourishment
to the retina. The retina comprises light sensitive tissue,
including rods and cones. The macula is located at the center of
the retina at the back of the eye, generally centered on an axis
passing through the centers of the lens and cornea of the eye
(i.e., the optic axis). The macula provides central vision,
particularly through cone cells.
[0003] Macular degeneration is a medical condition that affects the
macula, such that people suffering from macular degeneration may
experience lost or degraded central vision while retaining some
degree of peripheral vision. Macular degeneration may be caused by
various factors such as age (also known as "AMD") and genetics.
Macular degeneration may occur in a "dry" (nonexudative) form,
where cellular debris known as drusen accumulates between the
retina and the choroid, resulting in an area of geographic atrophy.
Macular degeneration may also occur in a "wet" (exudative) form,
where blood vessels grow up from the choroid behind the retina.
Even though people having macular degeneration may retain some
degree of peripheral vision, the loss of central vision may have a
significant negative impact on the quality of life. Moreover, the
quality of the remaining peripheral vision may be degraded and in
some cases may disappear as well. It may therefore be desirable to
provide treatment for macular degeneration in order to prevent or
reverse the loss of vision caused by macular degeneration. In some
cases it may be desirable to provide such treatment in a highly
localized fashion, such as by delivering a therapeutic substance in
the subretinal layer (under the neurosensory layer of the retina
and above the retinal pigment epithelium) directly adjacent to the
area of geographic atrophy, near the macula. However, since the
macula is at the back of the eye and underneath the delicate layer
of the retina, it may be difficult to access the macula in a
practical fashion.
[0004] While a variety of surgical methods and instruments have
been made and used to treat an eye, it is believed that no one
prior to the inventors has made or used the invention described in
the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] While the specification concludes with claims which
particularly point out and distinctly claim this technology, it is
believed this technology will be better understood from the
following description of certain examples taken in conjunction with
the accompanying drawings, in which like reference numerals
identify the same elements and in which:
[0006] FIG. 1 depicts a perspective view of an exemplary instrument
for subretinal administration of a therapeutic agent from a
suprachoroidal approach;
[0007] FIG. 2 depicts a perspective view of the distal end of an
exemplary cannula that may be incorporated into the instrument of
FIG. 1;
[0008] FIG. 3A depicts a cross-sectional side view of the cannula
of FIG. 2, with the cross-section taken along line 3-3 of FIG. 2,
with a needle in a first longitudinal position;
[0009] FIG. 3B depicts a cross-sectional side view of the cannula
of FIG. 2, with the cross-section taken along line 3-3 of FIG. 2,
with the needle in a second longitudinal position;
[0010] FIG. 4A depicts a cross-sectional view of an eye of a
patient, with a chandelier installed in the eye;
[0011] FIG. 4B depicts a cross-sectional view of the eye of FIG.
4A, with a suture loop attached to the eye, and with a sclerotomy
being performed;
[0012] FIG. 4C depicts a cross-sectional view of the eye of FIG.
4A, with the instrument of FIG. 1 being inserted through the
sclerotomy opening and in between the sclera and choroid of the
eye;
[0013] FIG. 4D depicts a cross-sectional view of the eye of FIG.
4A, with the instrument of FIG. 1 under direct visualization at the
back of the eye, between the sclera and choroid;
[0014] FIG. 4E depicts a cross-sectional view of the eye of FIG.
4A, with the needle of the instrument of FIG. 1 being advanced
under direct visualization at the back of the eye, pressing against
the outer surface of the choroid causing the choroid to "tent";
[0015] FIG. 4F depicts a cross-sectional view of the eye of FIG.
4A, with the needle dispensing a leading bleb under direct
visualization at the back of the eye, the needle between the sclera
and choroid, and the leading bleb in the sub retinal space between
the choroid and a retina;
[0016] FIG. 4G depicts a cross-sectional view of the eye of FIG.
4A, with the needle dispensing a therapeutic agent to the eye at
the back of the eye, between the sclera and choroid;
[0017] FIG. 5A depicts a detailed cross-sectional view of the eye
of FIG. 4A depicted in the state shown in FIG. 4E;
[0018] FIG. 5B depicts a detailed cross-sectional view of the eye
of FIG. 4A depicted in the state shown in FIG. 4F;
[0019] FIG. 5C depicts a detailed cross-sectional view of the eye
of FIG. 4A depicted in the state shown in FIG. 4G;
[0020] FIG. 6 depicts a cross-sectional view of the eye of FIG. 4A,
with the instrument of FIG. 1 at the back of the eye, between the
sclera and choroid, with the cannula of the instrument providing
substantial separation between the sclera and the choroid;
[0021] FIG. 7 depicts an enlarged view of the distal end of the
cannula of the instrument of FIG. 1 at the back of the eye, between
the sclera and choroid, with the cannula of the instrument
providing substantial separation between the sclera and the
choroid, with the needle of the instrument advanced to a distal
position;
[0022] FIG. 8 depicts a side elevational view of the distal end of
an exemplary alternative needle that may be incorporated into the
instrument of FIG. 1;
[0023] FIG. 9A depicts a cross-sectional side view of the cannula
of FIG. 2, with the cross-section taken along line 3-3 of FIG. 2,
with the needle of FIG. 8 in a first longitudinal position;
[0024] FIG. 9B depicts a cross-sectional side view of the cannula
of FIG. 2, with the cross-section taken along line 3-3 of FIG. 2,
with the needle of FIG. 8 in a second longitudinal position;
[0025] FIG. 9C depicts a cross-sectional side view of the cannula
of FIG. 2, with the cross-section taken along line 3-3 of FIG. 2,
with the needle of FIG. 8 in a third longitudinal position;
[0026] FIG. 10 depicts an enlarged view of the distal end of the
cannula of the instrument of FIG. 1 at the back of the eye, between
the sclera and choroid, with the needle of FIG. 8 disposed in the
cannula, with the cannula of the instrument providing substantial
separation between the sclera and the choroid, and with the needle
of FIG. 8 advanced to a distal position;
[0027] FIG. 11A depicts a cross-sectional side view of the needle
of FIG. 8 disposed in an exemplary alternative cannula that may be
incorporated into the instrument of FIG. 1, with the needle in a
proximal position; and
[0028] FIG. 11B depicts a cross-sectional side view of the needle
of FIG. 8 disposed in the cannula of FIG. 11A, with the needle in a
distal position.
[0029] The drawings are not intended to be limiting in any way, and
it is contemplated that various embodiments of the technology may
be carried out in a variety of other ways, including those not
necessarily depicted in the drawings. The accompanying drawings
incorporated in and forming a part of the specification illustrate
several aspects of the present technology, and together with the
description serve to explain the principles of the technology; it
being understood, however, that this technology is not limited to
the precise arrangements shown.
DETAILED DESCRIPTION
[0030] The following description of certain examples of the
technology should not be used to limit its scope. Other examples,
features, aspects, embodiments, and advantages of the technology
will become apparent to those skilled in the art from the following
description, which is by way of illustration, one of the best modes
contemplated for carrying out the technology. As will be realized,
the technology described herein is capable of other different and
obvious aspects, all without departing from the technology.
Accordingly, the drawings and descriptions should be regarded as
illustrative in nature and not restrictive.
[0031] It is further understood that any one or more of the
teachings, expressions, embodiments, examples, etc. described
herein may be combined with any one or more of the other teachings,
expressions, embodiments, examples, etc. that are described herein.
The following-described teachings, expressions, embodiments,
examples, etc. should therefore not be viewed in isolation relative
to each other. Various suitable ways in which the teachings herein
may be combined will be readily apparent to those of ordinary skill
in the art in view of the teachings herein. Such modifications and
variations are intended to be included within the scope of the
claims.
[0032] For clarity of disclosure, the terms "proximal" and "distal"
are defined herein relative to a surgeon or other operator grasping
a surgical instrument having a distal surgical end effector. The
term "proximal" refers the position of an element closer to the
surgeon or other operator and the term "distal" refers to the
position of an element closer to the surgical end effector of the
surgical instrument and further away from the surgeon or other
operator.
I. EXEMPLARY INSTRUMENT FOR SUBRETINAL ADMINISTRATION OF
THERAPEUTIC AGENT
[0033] FIG. 1 shows an exemplary instrument (10) that is configured
for use in a procedure for the subretinal administration of a
therapeutic agent to an eye of a patient from a suprachoroidal
approach. Instrument (10) comprises a body (20) and a flexible
cannula (50) extending distally from body (20). Cannula (50) of the
present example has a generally rectangular cross section, though
any other suitable cross-sectional profile (e.g., elliptical, etc.)
may be used. Cannula (50) is generally configured to support a
needle (100) that is slidable within cannula (50), as will be
described in greater detail below.
[0034] In the present example, cannula (50) comprises a flexible
material such as Polyether block amide (PEBA), which may be
manufactured under the trade name PEBAX. Of course, any other
suitable material or combination of materials may be used. Also in
the present example, cannula (50) has a cross-sectional profile
dimension of approximately 2.0 mm by 0.8 mm, with a length of
approximately 80 mm. Alternatively, any other suitable dimensions
may be used. As will be described in greater detail below, cannula
(50) is flexible enough to conform to specific structures and
contours of the patient's eye, yet cannula (50) has sufficient
column strength to permit advancement of cannula (50) between the
sclera and choroid of patient's eye without buckling. By way of
example only, cannula (50) may be configured and operable in
accordance with at least some of the teachings of U.S. Pub. No.
2015/0223977, entitled "Method and Apparatus for Subretinal
Administration of Therapeutic Agent," published Aug. 13, 2015, the
disclosure of which is incorporated by reference herein.
[0035] As can be seen in FIGS. 2-3B and 6, cannula (50) comprises a
body (52), a closed distal end (54), and a lateral opening (56)
that is located proximal to distal end (54). In the present
example, distal end (54) has a rounded configuration. It should be
understood that distal end (54) may have any suitable kind of
curvature. It should also be understood that distal end (54) may
have any other suitable kind of configuration (e.g., beveled,
etc.). In the present example, distal end (54) is configured to
provide separation between the sclera and choroid layers to enable
cannula (50) to be advanced between such layers while not
inflicting trauma to the sclera or choroid layers. Also in the
present example, the region of body (52) that defines lateral
opening (56) is beveled, as best seen in FIGS. 3A-3B.
Alternatively, the edge of lateral opening (56) may have any other
suitable configuration.
[0036] As best seen in FIGS. 3A-3B, a needle guide (60) is disposed
within the hollow interior of cannula (50). By way of example only,
needle guide (60) may be secured within cannula (50) by a press or
interference fit, by adhesives, by mechanical locking mechanisms,
and/or in any other suitable fashion. Needle guide (60) includes a
curved distal end (62) that leads to lateral opening (56) of
cannula (50), such that a lumen (64) of needle guide (60) distally
terminates at lateral opening (56). The portion of needle guide
(60) that is proximal to distal end (62) is substantially straight.
Needle guide (60) may be formed of plastic, stainless steel, and/or
any other suitable biocompatible material(s).
[0037] Needle (100) of the present example has a sharp distal tip
(102) and defines a lumen (104). Distal tip (102) of the present
example has a lancet configuration. In some other versions, distal
tip (102) has a tri-bevel configuration or any other configuration
as described in U.S. Pub. No. 2015/0223977, entitled "Method and
Apparatus for Subretinal Administration of Therapeutic Agent,"
published Aug. 13, 2015, the disclosure of which is incorporated by
reference herein. Still other suitable forms that distal tip (102)
may take will be apparent to those of ordinary skill in the art in
view of the teachings herein. Needle (100) of the present example
comprises a stainless steel hypodermic needle that is sized to
deliver the therapeutic agent while being small enough to minimize
incidental trauma as needle (100) penetrates tissue structures of
the patient's eye, as will be described in greater detail below.
While stainless steel is used in the present example, it should be
understood that any other suitable material(s) may be used,
including but not limited to nitinol, etc.
[0038] By way of example only, needle (100) may be 35 gauge with a
100 .mu.m inner diameter, although other suitable sizes may be
used. For instance, the outer diameter of needle (100) may fall
within the range of 27 gauge to 45 gauge; or more particularly
within the range of 30 gauge to 42 gauge; or more particularly
within the range of 32 gauge to 39 gauge. As another merely
illustrative example, the inner diameter of needle (100) may fall
within the range of approximately 50 .mu.m to approximately 200
.mu.m; or more particularly within the range of approximately 50
.mu.m to approximately 150 .mu.m; or more particularly within the
range of approximately 75 .mu.m to approximately 125 .mu.m.
[0039] Needle (100) is slidably disposed within lumen (64) of
needle guide (60). Needle guide (60) is generally configured to
direct needle (100) upwardly along an exit axis (EA) that is
obliquely oriented relative to the longitudinal axis (LA) of
cannula (50) through lateral opening (56) of cannula (50). This is
shown in the sequence depicted in FIGS. 3A-3B, in which FIG. 3A
shows needle (100) in a proximal position (where distal tip (102)
of needle (100) is fully contained in lumen (64) of needle guide
(60)); and FIG. 3B shows needle (100) in a distal position (where
distal tip (102) of needle (100) is outside of needle guide (60)).
While needle (100) is flexible, needle (100) of the present example
is resiliently biased to assume a straight configuration. Thus, as
shown in FIG. 3B, the portion of needle (100) that extends outside
of cannula (50) and needle guide (60) is substantially straight,
extending along exit axis (EA). In particular, at least a
substantial length of the portion of needle (100) that extends
outside of cannula (50) and needle guide (60) is coaxially aligned
with exit axis (EA).
[0040] It should be understood that the depiction of exit axis (EA)
in FIGS. 3A-3B may be somewhat exaggerated, for illustrative
purposes only. In some versions, curved distal end (62) is
configured to direct needle (100) along an exit axis (EA) that
extends distally from cannula (50) at an angle of approximately
7.degree. to approximately 9.degree. relative to the longitudinal
axis (LA) of cannula (50). It should be understood that such an
angle may be desirable to deflect needle (100) in a direction to
ensure penetration of needle into the choroid and to minimize the
possibility of needle (100) continuing beneath the choroid through
the suprachoroidal space (as opposed to penetrating through the
choroid) and the possibility of retinal perforation. By way of
further example only, curved distal portion (88) may urge needle
(100) to exit cannula (50) along an exit axis (EA) that is oriented
at an angle within the range of approximately 5.degree. to
approximately 30.degree. relative to the longitudinal axis (LA) of
cannula (50); or more particularly within the range of
approximately 5.degree. to approximately 20.degree. relative to the
longitudinal axis (LA) of cannula (50); or more particularly within
the range of approximately 5.degree. to approximately 10.degree.
relative to the longitudinal axis (LA) of cannula (50).
[0041] As shown in FIG. 1, instrument (10) of the present example
further comprises an actuation knob (26) located at the proximal
end of body (20). Actuation knob (26) is rotatable relative to body
(20) to thereby selectively translate needle (100) longitudinally
relative to cannula (50). In particular, actuation knob (26) is
rotatable in a first angular direction to drive needle (100)
distally relative to cannula (50); and in a second angular
direction to drive needle (100) proximally relative to cannula
(50). By way of example only, instrument (10) may provide such
functionality through knob (26) in accordance with at least some of
the teachings of U.S. Pub. No. 2015/0223977, entitled "Method and
Apparatus for Subretinal Administration of Therapeutic Agent,"
published Aug. 13, 2015, the disclosure of which is incorporated by
reference herein. Alternatively, any other suitable kind of
actuation feature(s) may be used to drive needle (100)
longitudinally relative to cannula (50).
[0042] In the present example, knob (26) is rotatable through a
complete range of motion that corresponds to advancement of needle
(100) to a position relative to cannula (50) to a predetermined
amount of penetration within an eye of a patient. In other words,
instrument (10) is configured such that an operator rotates knob
(26) until knob (26) can no longer rotate, or until knob (26)
begins to slip or "freewheel" in a clutch assembly, to properly
position needle (100) within an eye of a patient. In some examples,
the predetermined amount of advancement of needle (100) relative to
cannula (50) is between approximately 0.25 mm to approximately 10
mm; or more particularly within the range of approximately 0.1 mm
to approximately 10 mm; or more particularly within the range of
approximately 2 mm to approximately 6 mm; or more particularly to
approximately 4 mm.
[0043] In addition or in the alternative, instrument (10) may be
equipped with certain tactile feedback features to indicate to an
operator when needle (100) has been advanced to certain
predetermined distances relative to cannula (50). Accordingly, an
operator may determine the desired depth of penetration of needle
(100) into a patient's eye based on direct visualization of indicia
on instrument and/or based on tactile feedback from instrument
(10). Of course, such tactile feedback features may be combined
with the present example, as will be apparent to those of ordinary
skill in the art in view of the teachings herein.
[0044] As also shown in FIG. 1, a pair of supply tubes (30, 40)
extend proximally from actuator knob (26). In the present example,
first supply tube (30) is configured to couple with a source of
bleb fluid (340) (e.g., BSS); while second supply tube (40) is
configured to couple with a source of therapeutic agent (341). It
should be understood that each fluid supply tube (30, 40) may
include a conventional luer feature and/or other structures
permitting fluid supply tubes (30, 40) to be coupled with
respective fluid sources. Fluid supply tubes (30, 40) lead to a
valve assembly that includes actuation arms (24). Actuation arms
(24) are pivotable to selectively change the state of the valve
assembly. Based on the pivotal position of actuation arms (24), the
valve assembly is operable to selectively pinch or otherwise
open/close the supply of fluid from fluid supply tubes (30, 40) to
lumen (104) of needle (100). Thus, actuation arms (24) are operable
to selectively control the delivery of bleb fluid (340) and
therapeutic agent (341) via needle (100). By way of example only,
the valve assembly may be configured and operable in accordance
with at least some of the teachings of U.S. Pub. No. 2015/0223977,
entitled "Method and Apparatus for Subretinal Administration of
Therapeutic Agent," published Aug. 13, 2015, the disclosure of
which is incorporated by reference herein. Other suitable features
and configurations that may be used to control fluid delivery via
needle (100) will be apparent to those of ordinary skill in the art
in view of the teachings herein.
[0045] It should be understood that the features and operability of
instrument (10) may be varied in numerous ways. By way of example
only, needle (100) may be replaced with needle (200) as described
in greater detail below. In addition, cannula (50) may be replaced
with cannula (400) as will be described in greater detail below. In
addition, instrument (10) may be modified in accordance with at
least some of the teachings of U.S. Pub. No. 2015/0223977, entitled
"Method and Apparatus for Subretinal Administration of Therapeutic
Agent," published Aug. 13, 2015, the disclosure of which is
incorporated by reference herein; U.S. Pub. No. 2015/0351958,
entitled "Therapeutic Agent Delivery Device with Convergent Lumen,"
published Dec. 10, 2015, the disclosure of which is incorporated by
reference herein; U.S. Pub. No. 2015/0351959, entitled "Sub-Retinal
Tangential Needle Catheter Guide and Introducer," published Dec.
10, 2015, the disclosure of which is incorporated by reference
herein; U.S. Pub. No. 2016/0074212, entitled "Method and Apparatus
for Sensing Position Between Layers of an Eye," published Mar. 17,
2016, the disclosure of which is incorporated by reference herein;
U.S. Pub. No. 2016/0074217, entitled "Motorized Suprachoroidal
Injection of Therapeutic Agent," published Mar. 17, 2016, the
disclosure of which is incorporated by reference herein; U.S. Pub.
No. 2016/0074211, entitled "Therapeutic Agent Delivery Device with
Advanceable Cannula and Needle," published Mar. 17, 2016, the
disclosure of which is incorporated by reference herein; and/or
U.S. Pub. No. 2016/0081849, entitled "Therapeutic Agent Delivery
Device," published Mar. 24, 2016, the disclosure of which is
incorporated by reference herein. Other suitable modifications will
be apparent to those of ordinary skill in the art in view of the
teachings herein.
II. EXEMPLARY PROCEDURE FOR SUBRETINAL ADMINISTRATION OF
THERAPEUTIC AGENT
[0046] FIGS. 4A-5C show an exemplary procedure for subretinal
delivery of therapeutic agent from a suprachoroidal approach using
instrument (10) described above. By way of example only, the method
described herein may be employed to treat macular degeneration
and/or other ocular conditions. Although the procedure described
herein is discussed in the context of the treatment of age-related
macular degeneration, it should be understood that no such
limitation is intended or implied. For instance, in some merely
exemplary alternative procedures, the same techniques described
herein may be used to treat retinitis pigmentosa, diabetic
retinopathy, and/or other ocular conditions. Additionally, it
should be understood that the procedure described herein may be
used to treat either dry or wet age-related macular
degeneration.
[0047] In the present example, the procedure begins by an operator
immobilizing tissue surrounding a patient's eye (301) (e.g., the
eyelids) using a speculum, and/or any other instrument suitable for
immobilization. While immobilization described herein with
reference to tissue surrounding eye (301), it should be understood
that eye (301) itself may remain free to move. Once the tissue
surrounding eye (301) has been immobilized, an eye chandelier port
(314) is inserted into eye (301), as shown in FIG. 4A, to provide
intraocular illumination when the interior of eye (301) is viewed
through the pupil. In the present example, eye chandelier port
(314) is positioned in the inferior medial quadrant such that a
superior temporal quadrant sclerotomy may be preformed. Eye
chandelier port (314) is positioned to direct light onto the
interior of eye (301) to illuminate at least a portion of the
retina (e.g., including at least a portion of the macula). As will
be understood, such illumination corresponds to an area of eye
(301) that is being targeted for delivery of therapeutic agent.
[0048] In the present example, only chandelier port (314) is
inserted at the stage shown in FIG. 4A, without yet inserting an
optical fiber (315) into port (314). In some other versions, an
optical fiber (315) may be inserted into chandelier port (314) at
this stage. In either case, a microscope may optionally be utilized
to visually inspect the eye to confirm proper positioning of eye
chandelier port (314) relative to the target site. Although FIG. 4A
shows a particular positioning of eye chandelier port (314), it
should be understood that eye chandelier port (314) may have any
other positioning as will be apparent to those of ordinary skill in
the art in view of the teachings herein.
[0049] Once eye chandelier port (314) has been positioned, the
sclera (304) may be accessed by dissecting the conjunctiva by
incising a flap in the conjunctiva and pulling the flap
posteriorly. After such a dissection is completed, the exposed
surface (305) of the sclera (304) may optionally be blanched using
a cautery tool to minimize bleeding. Once conjunctiva dissection is
complete, the exposed surface (305) of the sclera (304) may
optionally be dried using a WECK-CEL or other suitable absorbent
device. A template may then be used to mark eye (301), as described
in U.S. Pub. No. 2015/0223977, entitled "Method and Apparatus for
Subretinal Administration of Therapeutic Agent," published Aug. 13,
2015, the disclosure of which is incorporated by reference herein.
An operator may then use a visual guide created using the template
to attach a suture loop assembly (332) and to perform a sclerotomy,
as shown in FIG. 4B, using a conventional scalpel (313) or other
suitable cutting instrument. The sclerotomy procedure forms a small
incision through sclera (304) of eye (301). The sclerotomy is
preformed with particular care to avoid penetration of the choroid
(306). Thus, the sclerotomy procedure provides access to the space
between sclera (304) and choroid (306). Once the incision is made
in eye (301), a blunt dissection may optionally be performed to
locally separate sclera (304) from choroid (306). Such a dissection
may be performed using a small blunt elongate instrument, as will
be apparent to those of ordinary skill in the art in view of the
teachings herein.
[0050] With the sclerotomy procedure performed, an operator may
insert cannula (50) of instrument (10) through incision (316) and
into the space between sclera (304) and choroid (306). As can be
seen in FIG. 4C, cannula (50) is directed through suture loop
assembly (332) and into the incision. Suture loop assembly (332)
may stabilize cannula (50) during insertion. Additionally, suture
loop assembly (332) maintains cannula (50) in a generally
tangential orientation relative to the incision. Such tangential
orientation may reduce trauma as cannula (50) is guided through the
incision. As cannula (50) is inserted into the incision through
suture loop assembly (332), an operator may use forceps or other
instruments to further guide cannula (50) along an atraumatic path.
Of course, use of forceps or other instruments is merely optional,
and may be omitted in some examples.
[0051] Although not shown, it should be understood that in some
examples cannula (50) may include one or more markers on the
surface of cannula (50) to indicate various depths of insertion.
While merely optional, such markers may be desirable to aid an
operator in identifying the proper depth of insertion as cannula
(50) is guided along an atraumatic path. For instance, the operator
may visually observe the position of such markers in relation to
suture loop assembly (332) and/or in relation to the incision in
the sclera (304) as an indication of the depth to which cannula
(50) is inserted in eye (301). By way of example only, one such
marker may correspond to an approximately 6 mm depth of insertion
of cannula (50).
[0052] As shown in FIG. 4D, once cannula (50) is at least partially
inserted into eye (301), an operator may insert an optical fiber
(315) into eye chandelier port (314) if the fiber (315) had not yet
been inserted at this stage. With eye chandelier port (314) in
place and assembled with optical fiber (315), an operator may
activate eye chandelier port (314) by directing light through
optical fiber (315) to provide illumination of eye (301) and
thereby visualize the interior of eye (301). Further adjustments to
the positioning of cannula (50) may optionally be made at this
point to ensure proper positioning relative to the area of
geographic atrophy of retina (308). In some instances, the operator
may wish to rotate the eye (301), such as by pulling on suture loop
assembly (332), to direct the pupil of the eye (301) toward the
operator in order to optimize visualization of the interior of the
eye (301) via the pupil.
[0053] FIGS. 4C-4D show cannula (50) as it is guided between sclera
(304) and choroid (306) to the delivery site for the therapeutic
agent. In the present example, the delivery site corresponds to a
generally posterior region of eye (301) adjacent to an area of
geographic atrophy of retina (308). In particular, the delivery
site of the present example is superior to the macula, in the
potential space between the neurosensory retina and the retinal
pigment epithelium layer. By way of example only, the operator may
rely on direct visualization through a microscope directed through
the pupil of eye (301) as cannula (50) is being advanced through
the range of motion shown in FIGS. 4C-4D, with illumination
provided through fiber (315) and port (314). Cannula (50) may be at
least partially visible through a retina (308) and choroid (306) of
eye (301). Visual tracking may be enhanced in versions where an
optical fiber is used to emit visible light through the distal end
of cannula (50).
[0054] Once cannula (50) has been advanced to the delivery site as
shown in FIG. 4D, an operator may advance needle (100) of
instrument (10) as described above by actuating knob (26). As can
be seen in FIGS. 4E and 5A, needle (100) is advanced relative to
cannula (50) such that needle (100) pierces through choroid (306)
without penetrating retina (308). Immediately prior to penetrating
choroid (306), needle (100) may appear under direct visualization
as "tenting" the surface of choroid (306). In other words, needle
(100) may deform choroid (306) by pushing upwardly on choroid
(306), providing an appearance similar to a tent pole deforming the
roof of a tent. Such a visual phenomenon may be used by an operator
to identify whether choroid (306) is about to be pierced and the
location of any eventual piercing. The particular amount of needle
(100) advancement sufficient to initiate "tenting" and subsequent
piercing of choroid (306) may be of any suitable amount as may be
determined by a number of factors such as, but not limited to,
general patient anatomy, local patient anatomy, operator
preference, and/or other factors. As described above, a merely
exemplary range of needle (100) advancement may be between
approximately 0.25 mm and approximately 10 mm; or more particularly
between approximately 2 mm and approximately 6 mm.
[0055] In the present example, after the operator has confirmed
that needle (100) has been properly advanced by visualizing the
tenting effect described above, the operator infuses a balanced
salt solution (BSS) or other similar solution as needle (100) is
advanced relative to cannula (50). Such a BSS may form a leading
bleb (340) ahead of needle (100) as needle (100) is advanced
through choroid (306). Leading bleb (340) may be desirable for two
reasons. First, as shown in FIGS. 4F and 5B, leading bleb (340) may
provide a further visual indicator to an operator to indicate when
needle (100) is properly positioned at the delivery site. Second,
leading bleb (340) may provide a barrier between needle (100) and
retina (308) once needle (100) has penetrated choroid (306). Such a
barrier may push the retinal wall outwardly, thereby minimizing the
risk of retinal perforation as needle (100) is advanced to the
delivery site. In some versions, a foot pedal is actuated in order
to drive leading bleb (340) out from needle (100). Alternatively,
other suitable features that may be used to drive leading bleb
(340) out from needle (100) will be apparent to those of ordinary
skill in the art in view of the teachings herein.
[0056] Once the operator visualizes leading bleb (340), the
operator may cease infusion of BSS, leaving a pocket of fluid as
can be seen in FIGS. 4F and 5B. Next, a therapeutic agent (341) may
be infused by actuating a syringe or other fluid delivery device as
described in various references cited herein. The particular
therapeutic agent (341) delivered may be any suitable therapeutic
agent configured to treat an ocular condition. Some merely
exemplary suitable therapeutic agents may include, but are not
necessarily limited to, drugs having smaller or large molecules,
therapeutic cell solutions, certain gene therapy solutions, tissue
plasminogen activators, and/or any other suitable therapeutic agent
as will be apparent to those of ordinary skill in the art in view
of the teachings herein. By way of example only, the therapeutic
agent (341) may be provided in accordance with at least some of the
teachings of U.S. Pat. No. 7,413,734, entitled "Treatment of
Retinitis Pigmentosa with Human Umbilical Cord Cells," issued Aug.
19, 2008, the disclosure of which is incorporated by reference
herein. In addition to, or as an alternative to, being used to
deliver a therapeutic agent (341), instrument (10) and variations
thereof may be used to provide drainage and/or perform other
operations.
[0057] In the present example, the amount of therapeutic agent
(341) that is ultimately delivered to the delivery site is
approximately 50 .mu.L, although any other suitable amount may be
delivered. In some versions, a foot pedal is actuated in order to
drive agent (341) out from needle (100). Alternatively, other
suitable features that may be used to drive agent (341) out from
needle (100) will be apparent to those of ordinary skill in the art
in view of the teachings herein. Delivery of therapeutic agent
(341) may be visualized by an expansion of the pocket of fluid as
can be seen in FIGS. 4G and 5C. As shown, therapeutic agent (341)
essentially mixes with the fluid of leading bleb (340) as
therapeutic agent (341) is injected into the surprachoroidal,
subretinal space.
[0058] Once delivery is complete, needle (100) may be retracted by
rotating knob (26) in a direction opposite to that used to advance
needle (100); and cannula (50) may then be withdrawn from eye
(301). It should be understood that because of the size of needle
(100), the site where needle (100) penetrated through choroid (306)
is self sealing, such that no further steps need be taken to seal
the delivery site through choroid (306). Suture loop assembly (332)
and chandelier (314) may be removed, and the incision in the sclera
(304) may be closed using any suitable conventional techniques.
[0059] As noted above, the foregoing procedure may be carried out
to treat a patient having macular degeneration. In some such
instances, the therapeutic agent (341) that is delivered by needle
(100) may comprise cells that are derived from postpartum umbilicus
and placenta. As noted above, and by way of example only, the
therapeutic agent (341) may be provided in accordance with at least
some of the teachings of U.S. Pat. No. 7,413,734, entitled
"Treatment of Retinitis Pigmentosa with Human Umbilical Cord
Cells," issued Aug. 19, 2008, the disclosure of which is
incorporated by reference herein. Alternatively, needle (100) may
be used to deliver any other suitable substance or substances, in
addition to or in lieu of those described in U.S. Pat. No.
7,413,734 and/or elsewhere herein. By way of example only,
therapeutic agent (341) may comprise various kinds of drugs
including but not limited to small molecules, large molecules,
cells, and/or gene therapies. It should also be understood that
macular degeneration is just one merely illustrative example of a
condition that may be treated through the procedure described
herein. Other biological conditions that may be addressed using the
instruments and procedures described herein will be apparent to
those of ordinary skill in the art.
[0060] It should also be understood that the procedure described
above may be carried out in accordance with any of the teachings of
U.S. Pub. No. 2015/0223977, entitled "Method and Apparatus for
Subretinal Administration of Therapeutic Agent," published Aug. 13,
2015, the disclosure of which is incorporated by reference herein;
U.S. Pub. No. 2015/0351958, entitled "Therapeutic Agent Delivery
Device with Convergent Lumen," published Dec. 10, 2015, the
disclosure of which is incorporated by reference herein; U.S. Pub.
No. 2015/0351959, entitled "Sub-Retinal Tangential Needle Catheter
Guide and Introducer," published Dec. 10, 2015, the disclosure of
which is incorporated by reference herein; U.S. Pub. No.
2016/0074212, entitled "Method and Apparatus for Sensing Position
Between Layers of an Eye," published Mar. 17, 2016, the disclosure
of which is incorporated by reference herein; U.S. Pub. No.
2016/0074217, entitled "Motorized Suprachoroidal Injection of
Therapeutic Agent," published Mar. 17, 2016, the disclosure of
which is incorporated by reference herein; U.S. Pub. No.
2016/0074211, entitled "Therapeutic Agent Delivery Device with
Advanceable Cannula and Needle," published Mar. 17, 2016, the
disclosure of which is incorporated by reference herein; and/or
U.S. Pub. No. 2016/0081849, entitled "Therapeutic Agent Delivery
Device," published Mar. 24, 2016, the disclosure of which is
incorporated by reference herein.
III. EXEMPLARY ALTERNATIVE NEEDLE FOR INSTRUMENT
[0061] Several variables may affect the relationship between the
exit angle (EA) of needle (100) and the choroid (306) of any given
patient. It should be understood that the choroid (306) and the
retina (308) are very thin and have relatively little structural
integrity. Thus, even when a very flexible cannula (50) is used,
cannula (50) may tend to provide substantial separation between the
choroid (306) and the sclera (304) as cannula (50) is inserted
between the choroid (306) and the sclera (304). The degree of
separation may vary from patient to patient (e.g., based on normal
anatomical variation and/or based on the patient's disease state,
etc.). In cases where the separation is truly substantial, the exit
angle (EA) of needle (100) may be insufficient to result in distal
tip (102) passing fully through the choroid (306). In other words,
needle (100) may continue through the suprachoroidal space without
fully penetrating the choroid (306).
[0062] FIG. 6 shows an exemplary scenario where cannula (50) has
elevated the choroid (306) and retina (308) away from the sclera
(304) to the point where a substantial gap (305) is defined between
the sclera (304) and the choroid (306). As also shown in FIG. 6,
the exit angle (EA) is oriented such that needle (100) would not
penetrate the choroid (306); and further such that needle (100)
would eventually engage the sclera (304). FIG. 7 shows needle (100)
advanced distally along this exit angle (EA). As shown, needle
(100) passes tangentially along the choroid (306) without ever
breaching the choroid (306). In some other instances, needle (100)
may pass partially through the choroid (306) and immediately exit
the choroid (306) without ever reaching the subretinal space
between the choroid (306) and the retina (308).
[0063] If the operator determines (e.g., based on the absence of a
choroidal "tenting" observation as described above) that needle
(100) has not fully penetrated the choroid (306) despite needle
(100) being advanced fully distally, the operator may retract
needle (100) proximally, slightly reposition cannula (50) and/or
another portion of instrument (10) in order to provide a better
orientation for the exit angle (EA), and then try advancing needle
(100) distally again. Even with such efforts, it may still be very
difficult or even impossible in some cases to successfully
penetrate the choroid (306) with needle (100). Even in cases where
efforts to reposition are successful, the success rate may be
highly dependent on the skill of the operator, and the
repositioning efforts will add time to the procedure. Moreover, the
repositioning may increase the risk of tissue trauma, increase the
risk of bleb collapse, and/or increase the risk of cell egress into
the suprachoroidal space.
[0064] It may seem apparent to address the above-noted issues by
simply modifying needle guide (60) to provide a steeper exit angle
(EA). However, this kind of modification may be unsuitable for many
patients. In particular, increasing the exit angle (EA) by
providing a more pronounced bend in distal end (62) of needle guide
(60) may increase the risk of needle (100) perforating the retina
(308) in some patients, particularly in those where the gap (305)
created by cannula (50) between the sclera (304) and the choroid
(306) is less pronounced than the gap (305) shown in FIGS. 6-7;
including cases where the gap (305) is non-existent. It may
therefore be desirable to provide a more nuanced solution that
provides greater consistency in penetration of the choroid (306)
without substantially increasing the risk of penetration of the
retina (308). Such a solution may provide better accommodation of
anatomical variations across patients; accommodate variation in
operator technique and expertise; and minimize the level of
operator training required.
[0065] FIG. 8 shows an exemplary alternative needle (200) that may
be incorporated into instrument (10) in place of needle (100). In
some instances, needle (200) may be substituted for needle (100)
without modifying any other aspects of instrument (10). Needle
(200) of the present example has a distal tip (202) that is
configured and operable just like distal tip (102) described above.
As shown in FIGS. 9A-9C, needle (200) also defines a lumen (204)
that is configured and operable just like lumen (104) described
above. Unlike needle (100), however, needle (200) of the present
example includes a substantially straight proximal portion (210), a
substantially straight distal portion (212), and a bent portion
(214) located between proximal and distal portions (210, 212). In
the present example, needle (200) is formed of nitinol, though it
should be understood that any other suitable material(s) (e.g.,
stainless steel, etc.) may be used.
[0066] Needle (200) is configured to provide bent portion (214) as
a preformed feature, such that needle (200) is resiliently biased
to assume the configuration shown in FIG. 6. By way of example
only, bent portion (214) may be configured to have a constant
radius of curvature between approximately 4 mm and approximately 15
mm; a constant radius of curvature between approximately 7 mm and
approximately 12 mm; a constant radius of curvature between
approximately 8 mm and approximately 11 mm; or a constant radius of
curvature between approximately 9 mm and approximately 10 mm. In
some versions, bent portion (214) has a radius of curvature of
approximately 10.5 mm. In some other versions, bent portion (214)
has a radius of curvature of approximately 10.0 mm. In some other
versions, bent portion (214) has a radius of curvature of
approximately 9.5 mm. It should be understood that the radius of
curvature must be carefully selected because if the radius is too
small, there may be an increased risk of perforating the retina
(308); and if the radius is too large, the needle (200) may still
fail to fully penetrate the choroid (306).
[0067] While the radius of curvature of bent portion (214) is
constant in the present example, in some other versions the radius
of curvature may be variable. For instance, some variations of
needle (200) may provide a larger radius of curvature in a region
of needle (200) that remains disposed in cannula (50), even when
needle (200) is in a distally extended position; with a smaller
radius of curvature in a region of needle (200) that extends
distally from cannula (50) when needle (200) is in a distally
extended position. This kind of configuration may impart a slight
precurvature to cannula (50), which may further assist in cannula
(50) conforming to the curved inner wall of sclera (304), which may
in turn reduce the occurrence (or magnitude) of gap (305).
[0068] As shown in FIGS. 9A-9C, needle (200) is slidably disposed
in needle guide (60) within cannula (50). While FIG. 9A shows
needle (200) in a partially advanced state, it should be understood
that needle (200) may be retracted further proximally in needle
guide (60) such that distal tip (202) does not protrude through
lateral opening (56). As shown in FIG. 9A, as needle (200) begins
to exit cannula (50) via lateral opening (56), the distally
protruding portion of needle (200) is oriented along a first exit
axis (EA.sub.1). At this stage, bent portion (214) and part of
distal portion (212) are still contained within needle guide (60),
such that needle guide (60) prevents needle (200) from reaching the
configuration shown in FIG. 8.
[0069] As the operator continues to advance needle (200) distally
relative to cannula (50), more of needle (200) protrudes distally
from lateral opening (56), as shown in FIG. 9B. Due to the
resilient bias of needle (200), the now longer protruding portion
of needle (200) is oriented along a second exit axis (EA.sub.2).
Second exit axis (EA.sub.2) defines an angle with the longitudinal
axis (LA) that is larger than the angle defined between first exit
axis (EA.sub.1) and the longitudinal axis (LA). As the operator
continues to advance needle (200) further distally relative to
cannula (50), even more of needle (200) protrudes distally from
lateral opening (56), as shown in FIG. 9C. Due to the resilient
bias of needle (200), the now longer protruding portion of needle
(200) is oriented along a third exit axis (EA.sub.3). Third exit
axis (EA.sub.3) defines an angle with the longitudinal axis (LA)
that is larger than the angle defined between second exit axis
(EA.sub.3) and the longitudinal axis (LA). Thus, the further needle
(200) is advanced, the larger the angle defined between the exit
axis (EA) and the longitudinal axis (LA). It should be understood
that the depictions of exit axes (EA.sub.1, EA.sub.2, EA.sub.3) in
FIGS. 9A-9C may be somewhat exaggerated, for illustrative purposes
only.
[0070] As shown in FIG. 10, needle (200) may be particularly useful
in cases where cannula creates a substantial gap (305) between the
sclera (304) and the choroid (306). It should be understood that
the gap (305) in FIG. 10 is substantially the same as the gap (305)
in FIG. 7. As noted above, due to the gap (305) in FIG. 7 and the
associated relationships between the anatomical structures and the
instrument (10) structures, needle (100) is unable to penetrate
choroid (306). However, as shown in FIG. 10, the curvature of
needle (200) allows needle (200) to penetrate choroid (306) despite
the presence of gap (305) and the associated relationships between
the anatomical structures and the instrument (10) structures.
[0071] As noted above, the exit angle (EA) of needle (200) varies
based on the extent to which needle (200) is extended from cannula
(50). It should be understood that this variation in the exit angle
(EA) will allow the operator to control the optimal exit angle (EA)
by controlling the amount of needle (200) extension. This may allow
for shallower angles (less extension) for some patients and steeper
angles (more extension) for other patients, to more consistently be
able to achieve penetration of the choroid (306) in a relatively
safe and efficient manner, eliminating the need for other
mitigations or workarounds that would otherwise be required from
the scenario depicted in FIG. 7.
IV. EXEMPLARY CANNULA NEEDLE FOR INSTRUMENT
[0072] As noted above, cannula (50) includes a closed distal end
(54) and a lateral opening (56) that is located proximal to distal
end (54). In some instances, it may be desirable to provide an
alternative cannula that has an open distal end, without a lateral
opening. By way of example only, this may provide simplified
manufacturing processes. Since it may still be desirable to have a
needle exit the cannula at such that the distal tip of the needle
is oriented along an axis that is oblique to the longitudinal axis
of the cannula, it may be desirable to use a needle with a
preformed curve in versions where the cannula has an open distal
end.
[0073] FIG. 11A shows an exemplary alternative cannula (400) that
may be readily incorporated into instrument (10) in place of
cannula (50). Cannula (400) of this example has a flexible body
(402) and a distal opening (406). Distal opening (406) is coaxially
positioned on the longitudinal axis of cannula (400) in this
example. In some other versions, distal opening (406) is offset
from the longitudinal axis of cannula (400). By way of example
only, cannula (400) may be formed of Polyether block amide (PEBA)
and/or any other suitable kind(s) of material(s). Like cannula
(50), cannula (400) of the present example has sufficient column
strength to be advanced distally between the sclera (306) and
choroid (308) of patient's eye without buckling.
[0074] An insert (408) is positioned within cannula (400). Insert
(408) may be secured within cannula (400) by a press or
interference fit, by adhesives, by mechanical locking mechanisms,
and/or in any other suitable fashion. In the present example,
insert (408) is formed of a polyimide material, though it should be
understood that any other suitable biocompatible material(s) may be
used. Insert (408) of the present example is substantially straight
yet may bend with cannula (400). Needle (200) is slidably disposed
in a lumen (410) defined by insert (408). When needle (200) is in a
proximal position as shown in FIG. 11A, distal tip (202) of needle
(200) is fully contained within lumen (410). At this stage, insert
(408) constrains needle (200) such that needle (200) is held under
stress in a substantially straight configuration. When needle (200)
is in a distal position as shown in FIG. 11B, distal tip (202) of
needle is positioned distally of cannula (400). At this stage,
curved portion (214) is exposed such that the distal portion (212)
of needle (200) is oriented along an exit axis that is oblique to
the longitudinal axis of cannula (400). It should be understood
that this configuration and orientation may position distal tip
(202) at the subretinal space (i.e., between the choroid (306) and
the retina (308)).
V. EXEMPLARY COMBINATIONS
[0075] The following examples relate to various non-exhaustive ways
in which the teachings herein may be combined or applied. It should
be understood that the following examples are not intended to
restrict the coverage of any claims that may be presented at any
time in this application or in subsequent filings of this
application. No disclaimer is intended. The following examples are
being provided for nothing more than merely illustrative purposes.
It is contemplated that the various teachings herein may be
arranged and applied in numerous other ways. It is also
contemplated that some variations may omit certain features
referred to in the below examples. Therefore, none of the aspects
or features referred to below should be deemed critical unless
otherwise explicitly indicated as such at a later date by the
inventors or by a successor in interest to the inventors. If any
claims are presented in this application or in subsequent filings
related to this application that include additional features beyond
those referred to below, those additional features shall not be
presumed to have been added for any reason relating to
patentability.
Example 1
[0076] An apparatus, comprising: (a) a body; (b) a cannula
extending distally from the body, wherein the cannula is flexible;
and (c) a needle slidably disposed in the cannula, wherein the
needle includes: (i) a sharp distal tip, wherein the needle is
configured to translate relative to the cannula between a proximal
position and a distal position, wherein the distal tip is
configured to be positioned inside the cannula when the needle is
in the proximal position, wherein the distal tip is configured to
be positioned outside the cannula when the needle is in the distal
position, and (ii) a curved portion, wherein the needle is
resiliently biased to extend along a curve through the curved
portion.
Example 2
[0077] The apparatus of Example 1, wherein the cannula includes:
(i) a closed distal end, and (ii) a lateral opening located
proximal to the closed distal end.
Example 3
[0078] The apparatus of Example 2, wherein the cannula further
includes a ramp feature, wherein the ramp feature extends from an
interior region of the cannula to the lateral opening.
Example 4
[0079] The apparatus of any one or more of Examples 1 through 3,
wherein the curved portion is resiliently biased to define a
constant radius of curvature.
Example 5
[0080] The apparatus of Example 4, wherein the radius of curvature
is between approximately 7 mm and approximately 12 mm.
Example 6
[0081] The apparatus of Example 4, wherein the radius of curvature
is between approximately 4 mm and approximately 15 mm.
Example 7
[0082] The apparatus of Example 4, wherein the radius of curvature
is between approximately 9 mm and approximately 10 mm.
Example 8
[0083] The apparatus of any one or more of Examples 1 through 7,
wherein the curved portion is configured to position the distal tip
at a progressively increasing exit angle relative to a longitudinal
axis of the cannula, based on a distance to which the needle is
advanced distally relative to the cannula.
Example 9
[0084] The apparatus of any one or more of Examples 1 through 8,
wherein the curved portion comprises a first curved region and a
second curved region, wherein the first curved region is located
near a distal portion of the needle, wherein the second curved
region is located proximal to the first curved region.
Example 10
[0085] The apparatus of Example 9, wherein the first curved region
has a first radius of curvature, wherein the second curved region
has a second radius of curvature, wherein the second radius of
curvature is greater than the first radius of curvature.
Example 11
[0086] The apparatus of any one or more of Examples 9 through 10,
wherein the first curved region is configured to not impart a
curvature to the cannula, wherein the second curved region is
configured to impart a curvature to the cannula.
Example 12
[0087] The apparatus of any one or more of Examples 1 through 11,
wherein the needle further includes a straight proximal portion and
a straight distal portion, wherein the curved portion is
longitudinally positioned between the straight proximal portion and
the straight distal portion.
Example 13
[0088] The apparatus of any one or more of Examples 1 through 12,
wherein the cannula defines an open distal end.
Example 14
[0089] The apparatus of Example 13, wherein the needle is
configured to protrude from the open distal end of the cannula when
the needle is in the distal position.
Example 15
[0090] The apparatus of any one or more of Examples 1 through 14,
further comprising a source of liquid therapeutic agent, wherein
the needle is operable to deliver the liquid therapeutic agent.
Example 16
[0091] The apparatus of Example 15, wherein the body includes: (i)
a needle actuator, wherein the actuator is operable to drive the
needle longitudinally relative to the cannula, and (ii) a valve
member, wherein the valve member is operable to selectively provide
fluid communication from the source of liquid therapeutic agent to
the needle.
Example 17
[0092] An apparatus, comprising: (a) a body; (b) a cannula
extending distally from the body, wherein the cannula is flexible,
wherein the cannula includes: (i) a closed distal end, and (ii) a
lateral opening located proximal to the closed distal end; and (c)
a needle slidably disposed in the cannula, wherein the needle
includes: (i) a sharp distal tip, wherein the needle is configured
to translate relative to the cannula between a proximal position
and a distal position, wherein the distal tip is configured to be
positioned inside the cannula when the needle is in the proximal
position, wherein the distal tip is configured extend past the
lateral opening when the needle is in the distal position, and (ii)
a curved portion, wherein the curved portion is configured to
provide an oblique exit angle to a portion of the needle extending
past the lateral opening when the needle is in the distal
position.
Example 18
[0093] The apparatus of Example 17, wherein the curved portion is
resiliently biased to assume a curved configuration, wherein the
curved portion is further configured to deform to a substantially
straight configuration within the cannula when the needle is in the
proximal position.
Example 19
[0094] A method of administering a therapeutic agent to an eye of a
patient, wherein the eye includes a sclera, a choroid, and a
retina, the method comprising: (a) inserting a flexible cannula
between the sclera and the choroid; (b) advancing a needle relative
to the cannula, thereby penetrating the choroid with a distal tip
of the needle, wherein the needle includes a preformed curve,
wherein the curve guides the needle toward a targeted region of the
choroid; and (c) administering the therapeutic agent to a region
between the choroid and the retina via the needle.
Example 20
[0095] The method of Example 19, wherein the act of advancing the
needle includes: (i) advancing the needle to a first longitudinal
position relative to the cannula, wherein the needle defines a
first exit angle relative to the cannula at the first longitudinal
position, and (ii) advancing the needle further distally to a
second longitudinal position relative to the cannula, wherein the
needle defines a second exit angle relative to the cannula at the
second longitudinal position, wherein the second exit angle is
greater than the first exit angle.
VI. MISCELLANEOUS
[0096] It should be understood that any of the versions of the
instruments described herein may include various other features in
addition to or in lieu of those described above. By way of example
only, any of the devices herein may also include one or more of the
various features disclosed in any of the various references that
are incorporated by reference herein.
[0097] It should be understood that any one or more of the
teachings, expressions, embodiments, examples, etc. described
herein may be combined with any one or more of the other teachings,
expressions, embodiments, examples, etc. that are described herein.
The above-described teachings, expressions, embodiments, examples,
etc. should therefore not be viewed in isolation relative to each
other. Various suitable ways in which the teachings herein may be
combined will be readily apparent to those of ordinary skill in the
art in view of the teachings herein. Such modifications and
variations are intended to be included within the scope of the
claims.
[0098] It should be appreciated that any patent, publication, or
other disclosure material, in whole or in part, that is said to be
incorporated by reference herein is incorporated herein only to the
extent that the incorporated material does not conflict with
existing definitions, statements, or other disclosure material set
forth in this disclosure. As such, and to the extent necessary, the
disclosure as explicitly set forth herein supersedes any
conflicting material incorporated herein by reference. Any
material, or portion thereof, that is said to be incorporated by
reference herein, but which conflicts with existing definitions,
statements, or other disclosure material set forth herein will only
be incorporated to the extent that no conflict arises between that
incorporated material and the existing disclosure material.
[0099] Versions described above may be designed to be disposed of
after a single use, or they can be designed to be used multiple
times. Versions may, in either or both cases, be reconditioned for
reuse after at least one use. Reconditioning may include any
combination of the steps of disassembly of the device, followed by
cleaning or replacement of particular pieces, and subsequent
reassembly. In particular, some versions of the device may be
disassembled, and any number of the particular pieces or parts of
the device may be selectively replaced or removed in any
combination. Upon cleaning and/or replacement of particular parts,
some versions of the device may be reassembled for subsequent use
either at a reconditioning facility, or by an operator immediately
prior to a procedure. Those skilled in the art will appreciate that
reconditioning of a device may utilize a variety of techniques for
disassembly, cleaning/replacement, and reassembly. Use of such
techniques, and the resulting reconditioned device, are all within
the scope of the present application.
[0100] By way of example only, versions described herein may be
sterilized before and/or after a procedure. In one sterilization
technique, the device is placed in a closed and sealed container,
such as a plastic or TYVEK bag. The container and device may then
be placed in a field of radiation that can penetrate the container,
such as gamma radiation, x-rays, or high-energy electrons. The
radiation may kill bacteria on the device and in the container. The
sterilized device may then be stored in the sterile container for
later use. A device may also be sterilized using any other
technique known in the art, including but not limited to beta or
gamma radiation, ethylene oxide, or steam.
[0101] Having shown and described various embodiments of the
present invention, further adaptations of the methods and systems
described herein may be accomplished by appropriate modifications
by one of ordinary skill in the art without departing from the
scope of the present invention. Several of such potential
modifications have been mentioned, and others will be apparent to
those skilled in the art. For instance, the examples, embodiments,
geometrics, materials, dimensions, ratios, steps, and the like
discussed above are illustrative and are not required. Accordingly,
the scope of the present invention should be considered in terms of
the following claims and is understood not to be limited to the
details of structure and operation shown and described in the
specification and drawings.
* * * * *