U.S. patent application number 12/072652 was filed with the patent office on 2008-06-26 for method and device for subretinal drug delivery.
This patent application is currently assigned to The Johns Hopkins University. Invention is credited to Eugene DeJuan, Terry Harrison Shelley, Signe Erickson Varner.
Application Number | 20080154204 12/072652 |
Document ID | / |
Family ID | 25392484 |
Filed Date | 2008-06-26 |
United States Patent
Application |
20080154204 |
Kind Code |
A1 |
Varner; Signe Erickson ; et
al. |
June 26, 2008 |
Method and device for subretinal drug delivery
Abstract
Devices and methods for the treatment of the eye are disclosed.
Preferred devices of the invention include a piercing member that
is inserted into the eye to create a pathway for a cannula. The
cannula is slidably mounted to the piercing member and is adapted
to reach a treatment site within the eye at which material is
injected into and/or withdrawn from the eye. The outer diameter of
the piercing member is small enough to allow for self-sealing of
the insertion site of the device upon the device's withdrawal
therefrom. Also disclosed are methods for the utilizing the devices
to treat the eye.
Inventors: |
Varner; Signe Erickson; (Los
Angeles, CA) ; DeJuan; Eugene; (La Canada, CA)
; Shelley; Terry Harrison; (Hampstead, MD) |
Correspondence
Address: |
Edwards Angell Palmer & Dodge LLP
P.O. Box 55874
Boston
MA
02205
US
|
Assignee: |
The Johns Hopkins
University
Baltimore
MD
|
Family ID: |
25392484 |
Appl. No.: |
12/072652 |
Filed: |
February 27, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
09888079 |
Jun 22, 2001 |
|
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12072652 |
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Current U.S.
Class: |
604/158 |
Current CPC
Class: |
A61F 9/0017
20130101 |
Class at
Publication: |
604/158 |
International
Class: |
A61M 5/31 20060101
A61M005/31 |
Claims
1. A device for treating an eye comprising: a piercing member
having a length, an outer diameter, a proximal end, a distal end,
and a lumen extending between the proximal and distal ends, the
distal end being of sufficient sharpness to cause a penetration of
the eye conjunctiva and sclera; and a cannula having a proximal
end, a distal end, a lumen extending between the proximal and
distal ends, and an outer diameter, wherein the cannula is slidably
disposed within the lumen of the piercing member and wherein the
distal end of the cannula is extendable beyond the distal end of
the piercing member; wherein the outer diameter of the piercing
member is sized to allow the length of the piercing member to be
advanced through the penetration, and for self sealing of the
penetration upon removal of the piercing member from the eye.
2. The device of claim 1 wherein the length of the piercing member
is such that the distal end of the piercing member is capable of
accessing any treatment site within the eye when the length of the
piercing member is inserted in the eye.
3. The device of claim 2 wherein the length of the piercing member
is in the range of 22 mm to 30 mm.
4. The device of claim 1 wherein the outer diameter of the piercing
member is 0.5 mm or less.
5. The device of claim 1 wherein a proximal portion of the device
is provided to remain outside of the eye after penetration by the
piercing member, and wherein angling of the proximal portion of the
device outside of the eye provides the distal end of the cannula
with access to multiple treatment sites via the penetration.
6. The device of claim 5 wherein the proximal portion of the device
comprises a handle having a length, a proximal end, a distal end,
and a substantially hollow portion, the distal end of the handle
being mounted to the piercing member.
7. The device of claim 1 wherein the cannula has a length such that
when the cannula is advanced through the lumen of the piercing
member, the proximal end of the cannula is capable of accessing any
treatment site within the eye.
8. The device of claim 1 wherein the outer diameter of the cannula
is in the range of 0.128 mm to 0.0457 mm.
9. The device of claim 1 wherein the cannula comprises
polyimide.
10. The device of claim 6 further comprising a quantity of tubing
having a proximal end, a distal end, and a lumen extending
therebetween, the distal end of the tubing being disposed within
the substantially hollow portion of the handle.
11. The device of claim 10 wherein the quantity of tubing is in
fluid connection with the cannula.
12. The device of claim 10 wherein the proximal end of the tubing
is adapted to be connected to a supply device.
13. The device of claim 10 wherein the proximal end of the tubing
is adapted to be connected to a syringe.
14. The device of claim 1 further comprising a rigid member having
a proximal end, a distal end, and a lumen therebetween, wherein the
rigid member is in connection with the cannula such that
distal-to-proximal movement and proximal-to-distal movement of the
rigid member affects movement of the cannula correspondingly.
15. The device of claim 14 wherein the cannula comprises polyimide
tubing.
16. The device of claim 14 wherein the proximal end of the rigid
member is connected to the distal end of the tubing,
17. The device of claim 16 wherein an epoxy is used to connect the
proximal end of the rigid member to the distal end of the tubing,
and the distal end of the rigid member to the proximal end of the
cannula.
18. The device of claim 1 further comprising a housing disposed in
the substantially hollow portion of the handle, the housing movable
in distal-to-proximal and proximal-to-distal directions.
19. The device of claim 18 wherein the housing that is movable in
distal-to-proximal and proximal-to-distal directions causes
corresponding movement of the cannula in distal-to-proximal and
proximal-to-distal directions.
20. The device of claim 19 wherein the housing is connected to an
actuating element, which can be manipulated by an operator to cause
corresponding movement of the housing.
21. A device for treating an eye comprising: a piercing member
having a length, an outer diameter, a proximal end, a distal end,
the distal end being of sufficient sharpness to cause a penetration
in the eye conjunctiva and sclera; a handle having a length, a
proximal end, a distal end, and a substantially hollow portion, the
distal end of the handle being mounted to the piercing member,
wherein the piercing member and the handle have a lumen
therebetween, defining a pathway between the proximal end of the
handle and distal end of the piercing member; a rigid member and
cannula slidably disposed within the lumen of the piercing member
and the handle, wherein rigid member has a proximal end, a distal
end, and a lumen therebetween, and the cannula has a proximal end,
a distal end, and a lumen therebetween, and the distal end of the
rigid member is connected to the proximal end of the cannula; and a
quantity of tubing having a proximal end, a distal end, and a lumen
extending therebetween, the distal end of the tubing being disposed
within the lumen of the handle and being connected to the proximal
end of the rigid member.
22. A device for treating an eye comprising: a piercing member
having a length, an outer diameter, a proximal end, a distal end,
and a lumen extending between the proximal and distal ends, the
distal end being of sufficient sharpness to cause a penetration in
the eye conjunctiva and sclera wherein the outer diameter of the
piercing member is sized to allow the length of the piercing member
to be advanced through the penetration, and for self sealing of the
penetration upon removal of the piercing member from the eye; a
fluid conduit comprising a cannula having a proximal end, a distal
end, a lumen extending between the proximal and distal ends, and an
outer diameter; and a rigid member having a proximal end, a distal
end, and a lumen therebetween, wherein the cannula is disposed
within the lumen of the rigid member, and wherein the rigid member
and cannula are both slidably disposed within the lumen of the
piercing member, and wherein the distal end of the cannula is
extendable beyond the distal end of the piercing member and the
distal end of the rigid member; wherein distal-to-proximal movement
and proximal-to-distal movement of the rigid member affects
movement of the cannula correspondingly.
Description
[0001] This application is a divisional application of U.S. patent
application Ser. No. 09/888,079, filed Jun. 22, 2001, which is
incorporated by reference herein in its entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention.
[0003] The present invention relates generally to the delivery of
medicaments, and more particularly, to devices and methods for
delivering therapeutic agents directly to intraocular tissue and
for withdrawing materials from within areas of the eye, such as the
vitreous humor. These devices and methods are advantageous for many
reasons, among which is that insertion of such a device into the
eye necessitates forming an insertion site that is small enough to
require no sutures to close, i.e., that is self-sealing, following
post-treatment removal of the device.
[0004] 2. Background
[0005] The delivery of drugs to the eye, especially the retina,
presents many challenges, most of which are owed to the geometry,
delicacy and/or behavior of the eye and its components.
[0006] For example, it is known in the art that ocular absorption
of systemically administered pharmacological agents and medicaments
is limited by the blood ocular barrier, i.e., tight junctions of
the retinal pigment epithelium and vascular endothelial cells. And
although high systemic doses of such medicaments and agents are
capable of penetrating this barrier in relatively small amounts, a
realistic risk of systemic toxicity accompanies such a course of
treatment.
[0007] Topical delivery of pharmacological agents and medicaments,
although involving fewer risks, has proven to be an equally
ineffective treatment method. Not only do the complex
hydrophobic/hydrophilic properties of the cornea and sclera hamper
absorption of topically delivered agents, but data also indicates
that it is not unusual for up to 85% of topically-applied agents to
be removed by the eye's blink mechanism/reflex.
[0008] Intravitreal injection of a drug is an effective means of
delivering the drug to the posterior segment of the eye in high
concentrations, but it necessarily requires follow-up injections in
order to maintain an adequate therapeutic concentration. This, in
turn, presents problems because each additional intraocular
injection carries with it a realistic risk of infection, hemorrhage
and/or retinal detachment.
[0009] Moreover, even if intravitreal injection techniques were not
otherwise problematic, such techniques have also proven inadequate
for performing cell transplantation and gene therapy, which
require, respectively, subretinal placement of cells and subretinal
delivery of gene vectors.
[0010] Several specific prior art techniques for subretinal
delivery of agents are known, e.g., those described in U.S. Pat.
Nos. 5,273,530 and 5,409,457. Another such approach is discussed in
Investigative Ophthalmology and Visual Science 30:1684 (1989),
which details a microspatula device for administering cells to the
eye through a trans-scleral or trans-corneal incision. Yet another
instrument employed by those in the art is a glass pipette, which
is used to replace cells in the retina by being introduced the eye
anteriorly through an incision via the scleral route (Investigative
Ophthalmology and Visual Science 28:1131(1987)).
[0011] Still other systems for subretinal drug injection, and for
gene delivery are described in Human Gene Therapy 11:449 (2000) and
Investigative Ophthalmology and Visual Science 35:2535 (1994). And
yet another instrument known in the art to serve this purpose is a
glass micro cannula.
[0012] A common feature of these techniques/instruments is that
they necessarily require the creation of a surgical incision at the
outset of a procedure, and/or the use of sutures following
completion of the procedure. This, in turn, increases the duration,
cost, and realistic risks of corneal ulceration, cataract
formation, intraocular infection, and/or vitreous loss that
accompany these procedures.
SUMMARY OF THE INVENTION
[0013] The present invention provides novel devices and methods for
the delivery of agents to the eye. More particularly, the present
invention relates to methods and devices for introducing materials
(e.g., therapeutic agents/medicaments such as genes, proteins,
cells, small molecule pharmaceuticals such as steroids and the
like, and sterile solutions) into the subretinal space of the eye.
The present device may also be used to effectuate the removal of
intravitreal fluid from the eye.
[0014] The devices and methods of the invention also are employed
to provide a localized deposit of a pharmaceutical agent within the
eye, particularly subretinally. For instance a steroidal
composition can be administered subretinally, wherein the steroid
resides as a solid (e.g. from an initial suspension administration)
and diffuses or otherwise is absorbed by the patient over time.
[0015] In an exemplary aspect of the present invention, the device
includes a piercing member that has adequate sharpness to penetrate
the sclera of a patient's eye. The piercing member may be connected
to a handle or gripping element, which facilitates grasping of the
device prior to and during use thereof.
[0016] The device further includes a cannula, which, in one aspect
of the invention, is slidably disposed within a passageway defined
within the device, and which, in another aspect of the invention,
is connected to, and positioned within a rigid member disposed
within this passageway. In the former aspect of the invention, the
cannula is directly connected to a distal end of a quantity of
tubing, while in the latter aspect, the rigid member is connected
to the distal end of the tubing.
[0017] In both aspects of the invention, the proximal end of the
quantity of tubing is attached to an externally located
injection/removal device. This device is adapted to supply and/or
withdraw fluid through the cannula, a distal end of which protrudes
from the piercing element and into proximity of a treatment/target
site within the eye.
[0018] In accordance with an exemplary method of the present
invention, the piercing member is advanced into and through the
sclera transconjunctively. The device is then advanced towards a
target/treatment site (e.g. the retina) until the distal end of the
cannula pierces the site.
[0019] Thereafter, the external device connected to the proximal
end of the tubing is activated to either inject material (e.g., an
agent/medicament) into the target site or to remove material
therefrom. Upon completion of the injection and/or removal of
material, the device is withdrawn from the target/treatment site,
and then from the patient's eye by reversing the steps of its
insertion.
[0020] During withdrawal of the device, the piercing member is
removed from the eye. Preferably, the piercing member is small
enough in size that the insertion site fashioned by the piercing
member is self-sealing (i.e., requiring no sutures to close)
following post-treatment removal of the piercing member
therethrough.
[0021] In a preferred aspect of the invention, the device delivers
an agent directly into the subretinal space of the patient's eye.
In such an embodiment, the device is directed towards the retina
such that the distal end of the cannula is advanced into, but not
beyond, the subretinal space. Accuracy of placement of the device
can be ensured/verified by techniques known in the art, e.g., by
injecting agent through the cannula until the formation of a
retinal detachment is observed. Injection of agent into this
dome-shaped retinal detachment also enables the delivered agent to
enjoy a prolonged residence time within the subretinal space. This,
in turn, allows the agent to provide a greater therapeutic effect,
without adversely affecting either intraocular pressure or
neighboring retinal cells.
[0022] The present subretinal injection device is a self-contained
system. Specifically, no separate surgical cannula systems are
required during use of a device in accordance with the present
invention. This allows for ease of handling of the device, which,
coupled with the fact that the insertion site is self-sealing upon
removal of the piercing member of the device, allows devices in
accordance with the present invention to be uniquely suited for
office-based procedures, which are comparatively less expensive,
shorter in duration, and carry with them fewer risks than
treatments necessitated by prior art systems and devices.
[0023] Moreover, because the insertion site is self-sealing upon
removal of the piercing member, use of this device is a preferred
treatment method as compared to currently known intraretinal
transplantation procedures, which require the creation of a
surgical incision prior to the treatment, and then the suturing of
the incision following completion of the treatment. Specifically,
in intraretinal transplantation techniques, a pars plana incision
is required to insert a glass micropipette or similar instrument
through the globe into the subretinal space. Upon completion of
such techniques, scleral and conjunctival sutures, neither of which
is required in accordance with the present invention, must be used
to close the incision.
[0024] Moreover, once an eye has been entered, an operator can
utilize the device of the present invention to treat multiple
target sites simply by varying the angle of the entry of the
device, thus avoiding the need for creation of multiple entry
sites. Even in the event, however, that multiple entry sites were
required, each entry site would be self-sealing as described
above.
[0025] Further, because agents are delivered directly to the
subretinal space by the device of the present invention, it follows
that higher concentrations of the agent are delivered to the
choroidal vessels and retinal pigment epithelial cells as compared
to intravitreal injection and intraocular implants that introduce
drugs into the vitreous humor. Injection into the subretinal space
may also provide for a more sustained delivery of the
agent/medicament to the retinal cells, thus avoiding a more rapid
clearance rate from the vitreous. In addition, this type of local
delivery may reduce the risk of elevated intraocular pressure
associated with prior devices, which provide sustained drug
delivery to the vitreous.
[0026] Other aspects of the invention are disclosed infra.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] FIG. 1 is a side view of an exemplary embodiment of a device
in accordance with the present invention;
[0028] FIG. 2 is a side view of an alternate embodiment of the
device of FIG. 1 in which the cannula is unsupported by a rigid
member;
[0029] FIG. 3A is a schematic view of the device of FIG. 2
following puncture of the sclera of the eye by the piercing member
of the device;
[0030] FIG. 3B is a schematic view of the device of FIG. 2/3A
following piercing of the retina by the cannula of the device.
[0031] FIG. 4A is a schematic view of the device of FIG. 2/3A
depicting use of the device to treat multiple treatment sites by
varying the angle of the portion of the device that lies outside of
the eye.
[0032] FIG. 4B is a schematic view of the device of FIG. 2/4A
following piercing of the retina by the cannula of the device.
DETAILED DESCRIPTION OF THE INVENTION
[0033] As stated above, new devices and methods are provided for
delivery of agents to the eye.
[0034] Referring now to the various figures of the drawings,
wherein like reference characters refer to like parts, there are
depicted in FIGS. 1-4 various views of surgical devices 10, 10' in
accordance with the present invention.
[0035] As shown in FIG. 1, a first exemplary embodiment of the
device 10 of the present invention includes a piercing member 12,
which has a proximal end 14 and a distal end 16, with a lumen
defined therebetween. The distal end 16 of the piercing member 12
is pointed (e.g., beveled) to allow for the piercing member to
pierce and penetrate a target/treatment site as will be described
below.
[0036] In an exemplary embodiment of the present invention, the
piercing member 12 has an outer diameter of about 25 gage (0.5
millimeter) or less and a length, P, in the range of about 6
millimeters to 25 millimeters, preferably in the range of about 15
millimeters to 20 millimeters.
[0037] The piercing member lumen should have a substantially
constant diameter, which generally is in the range of about 0.152
millimeter to 0.305 millimeter.
[0038] The piercing member 12 may be made of a variety of
biocompatible materials, including, but not limited to, polymers,
metals and composites. Generally however, the piercing member 12 is
made of a stainless steel.
[0039] The proximal end 14 of the piercing member 12 is connected,
via a technique known in art (e.g., press fitting, and/or via an
adhesive or an epoxy) to a first connection element 18.
[0040] The first connection element 18 has a proximal end 20 and a
distal end 22 and a lumen defined therebetween. The first
connection element lumen should have a diameter that is
substantially identical to that of the piercing member lumen such
that, upon connection of the proximal end 16 of the piercing member
12 to the distal end 22 of the first connection element 18, these
lumen are substantially longitudinally aligned to create a fluid
tight passageway.
[0041] The first connection element 18 may be made of a variety of
biocompatible materials, including, but not limited to, polymers,
metals and composites. Generally, the element 18 is made of
titanium, stainless steel, nitinol or, preferably, delrin.
[0042] Optionally, but preferably, a seal 24 is connected to the
first connection element 18, and substantially surrounds at least a
portion of the first connection member lumen in order to further
enhance the integrity of the fluid tight passageway. The seal 24
may be slidably connected to the first connection element 18 and/or
may be connected via techniques known in the art, e.g., via an
adhesive or an epoxy. The seal 24 can be made of a variety of
materials, but is generally made of silicone.
[0043] The fluid tight passageway is sized to accommodate a rigid
member 26, which adds physical stability to the device 10. The
rigid member 26 has a proximal end 28 and a distal end 30, and a
lumen defined therebetween. The distal end 30 of the rigid member
26 extends distal to the distal end 16 of the piercing member,
while the proximal end 28 of the rigid member extends proximate to
the seal 24.
[0044] A cannula 44 is disposed within the rigid member 26.
Preferably, the cannula 44 is physically connected to the rigid
member 26 (e.g., via adhesive, sealant, or epoxy or via other
techniques known in the art) such that any distal-to-proximal or
proximal-to-distal movement of the rigid member effects
corresponding movement of the cannula, and such that any
distal-to-proximal movement of the cannula effects corresponding
movement of the rigid member.
[0045] The cannula 44 has a length, C, such that, when disposed
within the rigid member 26, a distal portion 46 of the cannula is
distal to the distal end 30 of the rigid member, while a proximal
end 48 of the cannula extends proximal to the distal end 34 of the
tubing 32.
[0046] It is understood, however, that the length, C, of the
cannula 44 may be shorter or longer than depicted in FIG. 1. For
example, the distal portion 46 of the cannula may extend further
beyond the distal end 30 of the rigid member 26, and/or the
proximal end 48 of the cannula may extend further proximately
within the tubing or beyond the proximal end 42 of the tubing.
[0047] The length, C, of the cannula 44 is generally in the range
of about 35 millimeters to 75 millimeters with its distal portion
46 generally having a length in the range of about 1 millimeter to
3 millimeters.
[0048] Generally, the outer diameter of the rigid member is about
28 gage (0.32 mm) or less, while the outer diameter of the cannula
44 in the range of about 38 gage (0.128 millimeter) to 45 gage
(0.0457) millimeter.
[0049] Both the rigid member 26 and the cannula 44 can be made of a
variety of biocompatible materials, including, but not limited to,
polymers, metals and composites. In an exemplary embodiment of the
present invention, the cannula 20 is made of polyimide tubing,
while the rigid member 26 is made of either polyimide, titanium,
nitinol, or, preferably, stainless steel.
[0050] As shown in FIG. 1, the rigid member 26 extends into a
quantity of tubing 32 such that the proximal end 28 of the rigid
member is proximal to the distal end 34 of the tubing. In an
exemplary embodiment of the present invention, the tubing 32 and
the rigid member 26 also are physically connected to each other
(e.g., via an adhesive, a sealant, an epoxy or via other techniques
known in the art) such that any distal-to-proximal or
proximal-to-distal movement of the tubing effects corresponding
movement of the rigid member (and, therefore, of the cannula as
well), and such that any distal-to-proximal movement of either the
rigid member or the cannula effects corresponding movement of the
tubing.
[0051] Preferably, a second connection element 36 surrounds a
distal portion 38 of the tubing 32 and a proximal portion 40 of the
rigid member 26 in order to maintain the connection between the
tubing and rigid member. The second connection element is connected
to the tubing 32 and rigid member by a suitable technique known in
the art, e.g., press fitting and/or via use of an adhesive or an
epoxy.
[0052] The second connection element 36 may be made of a variety of
biocompatible materials, including, but not limited to, polymers,
metals and composites. Generally, the second connection element 36
is made of titanium, polyimide, nitinol, stainless steel or,
preferably, delrin.
[0053] The tubing 32 includes a proximal end 42, which is in
communication with an external supply or withdrawal device (not
shown) either directly or via a connection element (e.g., a luer
fitting). This connection allows for material (e.g., fluid, air,
etc.) to be supplied into, or withdrawn from the tubing, each as
will be discussed below.
[0054] Exemplary materials of which the tubing may be formed
include, but are not limited to, a polymer, with preferred
materials being silicon and polyimide.
[0055] Referring now to FIG. 2, it depicts an alternate embodiment
of the device 10 of FIG. 1. The device 10' is similar in both
structure and operation to the device 10 of FIG. 1, but includes a
handle 50 and does not utilize a rigid member 26.
[0056] The device 10' of FIG. 2 includes a piercing member 12'
substantially as described above except that the length of the
piercing member is preferably in the range of about 22 millimeters
to 30 millimeters.
[0057] The proximal end 14' of the piercing member 12' is connected
to the distal end 52 of a handle 50, which has a proximal end 54
that is connected to a quantity of tubing 32'. By virtue of its
connection to both the piercing member 12' and the tubing 32', the
handle 50 is not only effective to facilitate initial and continued
grasping of the device 10', but also to stabilize and provide
support to the device 10'.
[0058] Each of the handle 50, the piercing member 12' and the
tubing 32' has a lumen defined therebetween, thus defining a
pathway between the distal end 16' of the piercing member and the
proximal end 42' of the tubing.
[0059] A cannula is disposed within, and, preferably, connected to
the lumen 60 defined within the tubing 32'. The tubing 32' and
cannula 44' may be connected as is generally known in the art,
e.g., via an adhesive, a sealant or an epoxy. By virtue of this
connection, distal-to-proximal and proximal-to-distal movement of
the tubing 32' will result in corresponding movement of the cannula
44', and vice versa.
[0060] The cannula 44' generally has identical length and outer
diameter parameters to the cannula 44 of FIG. 1, and generally is
made of the same material as well.
[0061] The handle 50 also includes an actuating element 56 that
sits within a slot (not shown) or other opening. The actuating
element 56 is in communication with a housing 58, which is in
communication with the distal end 34' of the tubing 32' as shown in
FIG. 2. By virtue of this arrangement, distal-to-proximal or
proximal-to-distal movement of the actuating element 56 within the
slot causes substantially corresponding movement of the housing,
which, in turn, causes substantially corresponding movement of the
tubing and, therefore, of the cannula 44' as well.
[0062] Exemplary materials from which the handle 50 and housing 58
may be made include, but are not limited to, biocompatible
materials such as polymers (e.g., acetal, polyphenylene sulfide,
polypropylene, ABS plastic), metals (e.g., stainless steel), and
composites. Preferably, the handle 50 is made of acetal. The
housing 58 may also be made of teflon or nylon. In an exemplary
embodiment of the present invention, the handle 50 and the housing
58 are made of the same material.
[0063] The devices of FIGS. 1 and 2 are used to treat one or more
target/treatment sites, each of which is generally located within
an eye. Although the description of FIGS. 3A-B and 4A-B below refer
to use of the device of FIG. 2, these descriptions also are
applicable to use of the device of FIG. 1. Also, all common
elements of the devices 10, 10' of FIGS. 1 and 2 will be referred
to in these descriptions by their FIG. 2 reference numbers.
[0064] Referring now to FIG. 3A, in preparation for its use, the
device 10' gains access to the vitreous humor 102 of a human eye
100. This occurs by placing enough pressure onto the device 10'
such that the sharp distal end 18' of the piercing member 12'
penetrates the sclera 104 of the eye 100, thus creating a
continuous passageway (not shown) between the device and the
vitreous humor 102 of the eye 100.
[0065] The piercing member 12' has a length, P (see FIG. 1) such
that once its proximal end 16' is in contact with a portion of the
outer periphery of the sclera 104, it is ensured that the distal
end 18 of the piercing instrument is within the vitreous humor 102
of the eye 100. Once inserted as such, the piercing member 12' can
be angled by gently tilting any portion of the device 10' that lies
outside of the eye 100. This allows the device 10' to treat
multiple target sites within the eye 38 without necessitating
multiple, separate insertions of the device into the eye.
[0066] It is understood that although the process of inserting the
piercing member 12' into the vitreous humor 102 is depicted in FIG.
3 as occurring while the cannula 44' is partially inserted within
the device 10, the process may occur either with or without the
cannula being entirely or partially within the device.
[0067] Once a passageway into the eye 100 is created as such, the
cannula 44' and attached tubing 32' (or, in the case of the device
10 of FIG. 1, the rigid member 26 with attached cannula 44
positioned therewithin) is advanced into and through the device 10'
and to a treatment/target site. In FIGS. 3B and 4B, the target site
is the retina 110 of the eye 100, but it is understood that the
target site may be any portion of the eye.
[0068] In an embodiment in which the retina 110 is the target site,
the cannula 44' is guided through the device 10' until a distal
portion 46' of the cannula emerges from the guiding member 12', and
into the vitreous humor 102.
[0069] The cannula 44' is further advanced within the eye 100 until
the distal portion 46' of the cannula enters the retina 110. An
operator of the device 10' is able to determine that the distal
portion 46' of the cannula 44' has entered, but not traveled
completely through, the retina 48 by virtue of techniques generally
known in the art.
[0070] For example, once an operator estimates that the distal
portion 46' of the cannula is approaching the retina, s/he can
inject an agent through the cannula 44'. In order to simplify this
estimation, the cannula 44' can include one or more markings that
serve as visual and/or tactile indicators of the relative position
of the cannula with respect to the retina. If, following this
injection, the formation of a retinal detachment is observed, the
operator can safely deduce that the distal portion 46' of the
cannula 44' has entered, and still remains within, the retina 110
and can halt the distal advancement of the cannula.
[0071] Once proper positioning of the distal portion 46' of the
cannula 44' at/within the treatment/target site 110 is ensured, the
device may be utilized either to deliver or withdraw material from
the eye 100. This occurs by activation of an externally located
supply or withdrawal device (not shown) connected to the proximal
end 42' of the tubing 32'. Preferably, this externally located
device is connected to the tubing 32' by a connection device (not
shown), e.g., a luer fitting or other connection device known in
the art.
[0072] In an embodiment in which material is supplied to a
treatment site, the material is infused into the proximal end 42'
of the tubing 32' via an externally located supply device. The
material travels through the tubing 32', wherein a quantity of the
material is forced into the proximal end 48' of the cannula 44',
through which it travels until it exits the distal portion 46' of
the cannula.
[0073] In an embodiment in which material is withdrawn from a
treatment site, an aspiration force is supplied through the tubing
32'. A sufficient amount of this force enters the proximal end 48'
of the cannula 44' to enable material to be drawn into the distal
portion 46' of the cannula 44' from the treatment site. This
material then travels though the cannula 44', out its proximal end
48', into the tubing 32', and out the proximal end 42' of the
tubing to an externally located collection device (not shown).
[0074] In an embodiment wherein material is delivered to the retina
through an externally located supply device (e.g., a syringe), such
material is generally a therapeutic agent or medicament, but may be
any entirely or partially liquid-based or airborne material.
Exemplary medicaments/agents include, but are not limited to, small
molecule therapeutics, genes, proteins, or cells.
[0075] Among the uses for these agents/medicaments that are
supplied to the retina 10 are for treatment of such
problems/disorders as retinal detachment, vascular occlusions,
proliferative retinopathy, diabetic retinopathy, inflammations such
as uveitis, choroiditis and retinitis, degenerative disease,
vascular diseases and various tumors including neoplasms.
[0076] It is understood that the amount of agent/medicament
required to be delivered to the treatment site will vary depending
on the treatment circumstances and will be readily calculable by
one of ordinary skill in the art without undue experimentation.
[0077] In an exemplary embodiment in which materials are removed
via the device 10', the treatment site may be the vitreous humor
102 of the eye 100. For example, portions of the vitreous humor 102
may be removed through the device 10' during a vitrectomy--a
procedure often used to treat a variety of eye diseases, ocular
injuries and complicated retinal detachments.
[0078] In accordance with an exemplary method of the present
invention, the piercing member 12' is advanced into and through the
sclera 104 (e.g., transconjunctively), thereby penetrating the eye
100. The cannula 44' (which is connected to the rigid member 26 in
the embodiment of FIG. 1, and connected to the tubing 32' in the
embodiment of FIG. 2) is then advanced through the device 10', then
into and through the vitreous humor 102 to a target site, (e.g. the
retina 110), such that the distal portion 46' of the cannula 44'
pierces the target site.
[0079] An infusion or aspiration device (not shown) connected to
the proximal end 42' of the tubing 32' is then activated to either
inject material into the target site or to remove material
therefrom as described above.
[0080] Upon completion of the injection and/or removal step, the
cannula 44' is withdrawn from the eye 100 by reversing the steps of
its insertion, after which the piercing member 12' is removed from
the eye. Preferably, the piercing member has a small enough outer
diameter, e.g., about 25 gage (0.4547 millimeters) or less, that
the incision made by the piercing member to gain entry into and
through the eye 100 is self-sealing, i.e., requiring no sutures for
post-treatment closure.
[0081] In a particularly preferred embodiment, the device 10' is
used to deliver an agent directly into the subretinal space 110 of
a patient's eye 100. Once the distal portion 46' of the cannula 44'
is properly positioned within the subretinal space 110, medicament
is injected therein, thus raising a dome-shaped retinal detachment
(not shown) that allows for the delivered medicament to enjoy a
prolonged residence time within the subretinal space. This, in
turn, allows the medicament to provide a greater therapeutic
effect, without adversely affecting intraocular pressure or
neighboring retinal cells, both of which are problems that plague
procedures in which drugs are administered directly into the
vitreous humor 102.
[0082] The present subretinal injection device 10' is a
self-contained system, i.e., no additional devices other than those
discussed in accordance with the embodiments described above must
be employed during use of the device. Moreover, the insertion site
of the piercing member 12' is self-sealing, also as discussed
above.
[0083] These features of the present invention allow the device 10'
to be uniquely suited to office-based procedures (i.e., procedures
that are not required to take place in a hospital setting). Such
office-based procedures are comparatively less expensive, shorter
in duration, and carry with them less risk than treatments
necessitated by prior art systems and devices.
[0084] Moreover, because the area of entry of the device 10' is
self-sealing upon removal of the device, use of this device is a
preferred treatment method as compared to intraretinal
transplantation, which requires surgically opening the eye.
Specifically, in intraretinal transplantation techniques, a pars
plana incision is required to insert a glass micropipette or
similar instrument through the globe and into the subretinal space.
Upon completion of the procedure, scleral and conjunctival sutures
are required to close the incision. As indicated above, this
results in a prolonged procedure and/or an increased risk of
infection, problems which are avoided due to the insertion site for
the piercing member 12' of the present invention being
self-sealing.
[0085] Another advantage of a device 10' of the present invention
is that an operator may use it to treat multiple treatment sites
simply by varying the angle of the portion of the device that lies
outside of the eye 100, for example, as depicted in FIGS. 3A-4B,
thus avoiding the need for creation of multiple entry sites. Even
in the event, however, that multiple entry sites were required,
each entry site would be self-sealing as described above.
[0086] Further, because the agents are delivered directly to the
subretinal space by the device 10' of the present invention, it
follows that higher concentrations of the agent/medicament are
delivered to the choroidal vessels and retinal pigment epithelial
cells as compared to intravitreal injection and intraocular
implants that introduce drugs into the vitreous humor. Moreover,
the local delivery accomplished by the present device 10' and
methods may also reduce the risk of elevated intraocular pressure
associated with prior devices that provide sustained drug delivery
to the vitreous humor.
[0087] The present device further provides a method for direct
intraretinal injection of therapeutics. Properly designed
formulations delivered in such a manner result in sustained local
delivery to retinal tissues, while reducing the risk of affecting
intraocular pressure that accompanies intravitreal implants.
[0088] The present invention also includes kits (not shown) that
comprise one or more devices 10' in accordance with the invention.
Such kits also may include equipment (e.g., one or more containers,
and aerosol canisters) for use with the device(s) 10', and/or
written instructions for use of the device(s) and/or the
equipment.
[0089] The invention also includes kits that comprise one or more
devices of the invention, preferably packaged in sterile condition.
Kits of the invention may include, e.g., one or more piercing
members with contained cannula, preferably packaged in sterile
condition, and/or written instructions for use of the device and
other components of the kit.
[0090] The foregoing description of the invention is merely
illustrative thereof, and it is understood that variations and
modifications can be effected without departing from the scope or
spirit of the invention as set forth in the following claims. All
documents mentioned herein are incorporated by reference herein in
their entirety.
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