U.S. patent application number 17/537810 was filed with the patent office on 2022-05-26 for treatment of the ear.
The applicant listed for this patent is Cochlear Limited. Invention is credited to Marcus Andersson, Jonathon Kirk, Daniel Smyth, Claudiu G. Treaba, Kristien Johanna Maria Verhoeven.
Application Number | 20220161009 17/537810 |
Document ID | / |
Family ID | |
Filed Date | 2022-05-26 |
United States Patent
Application |
20220161009 |
Kind Code |
A1 |
Verhoeven; Kristien Johanna Maria ;
et al. |
May 26, 2022 |
TREATMENT OF THE EAR
Abstract
Presented herein are implantable systems and methods for
long-term delivery of treatment substance to a recipient.
Inventors: |
Verhoeven; Kristien Johanna
Maria; (Mechelen, BE) ; Smyth; Daniel;
(Mechelen, BE) ; Kirk; Jonathon; (Centennial,
CO) ; Treaba; Claudiu G.; (New York, NY) ;
Andersson; Marcus; (Goteborg, SE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Cochlear Limited |
Macquarie University |
|
AU |
|
|
Appl. No.: |
17/537810 |
Filed: |
November 30, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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16547952 |
Aug 22, 2019 |
11213662 |
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17537810 |
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15450112 |
Mar 6, 2017 |
10406334 |
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16547952 |
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14315825 |
Jun 26, 2014 |
9616207 |
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15450112 |
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International
Class: |
A61M 31/00 20060101
A61M031/00; A61M 5/142 20060101 A61M005/142; A61M 5/148 20060101
A61M005/148; A61F 11/00 20060101 A61F011/00; A61M 5/168 20060101
A61M005/168 |
Claims
1. An apparatus, comprising: a reservoir configured to be implanted
at least under skin of a recipient, wherein the reservoir is
configured to have a treatment substance positioned therein; a
delivery tube having a proximal end fluidically coupled to the
reservoir and a distal end; and at least one resiliently flexible
portion configured to deform in response to application of a user
applied external force applied through the skin of the recipient so
as to advance a portion of the treatment substance through the
delivery tube to the distal end of the delivery tube.
2. The apparatus of claim 1, wherein the at least one resiliently
flexible portion comprises a portion of the reservoir.
3. The apparatus of claim 1, further comprising: a check valve
fluidically coupling the reservoir to the delivery tube.
4. The apparatus of claim 3, wherein the check valve comprises: a
magnetically activated check valve fluidically coupling the
reservoir to the delivery tube, wherein the magnetically activated
check valve is configured to open in response to an externally
applied magnetic field.
5. The apparatus of claim 1, further comprising an expansion tube
disposed between the reservoir and the delivery tube, and wherein
the at least one resiliently flexible portion comprises a portion
of the expansion tube.
6. The apparatus of claim 1, further comprising: a secondary
reservoir connected between the reservoir and the delivery
tube.
7. The apparatus of claim 1, further comprising: an implanted
magnetic positioning member located adjacent the at least one
resiliently flexible portion.
8. The apparatus of claim 1, further comprising: one or more
fixation mechanisms configured to retain various components of the
apparatus at a selected implanted location in the recipient.
9. The apparatus of claim 8, wherein at least one fixation
mechanism comprises an elongate wire extending through a section of
the delivery tube.
10. The apparatus of claim 8, wherein at least one fixation
mechanism comprises an elongate wire mesh disposed around a section
of the delivery tube.
11. The apparatus of claim 8, wherein at least one of the one or
more fixation mechanisms comprises: an implantable delivery tube
positioning mechanism comprising a first extension arm configured
to be secured to tissue of the recipient and a second extension arm
configured to retain a portion of the delivery tube, wherein the
first and second extension arms are connected by a joint that
permits adjustment of the second extension arm relative to the
first extension arm.
12. The apparatus of claim 1, further comprising a delivery device
disposed at the distal end of the delivery tube.
13. The apparatus of claim 1, wherein the at least one resiliently
flexible portion forms part of the apparatus that is configured to
have the treatment substance disposed therein.
14. A method, comprising: implanting, in a recipient, an apparatus
comprising an implantable reservoir, a delivery tube, and at least
one resiliently flexible portion, wherein the implantable reservoir
is configured to have a treatment substance disposed therein,
wherein the delivery tube has a proximal end fluidically coupled to
the implantable reservoir and a distal end, and wherein the at
least one resiliently flexible portion is implanted adjacent skin
of the recipient; and receiving, through the skin of the recipient,
a user applied external force to cause the at least one resiliently
flexible portion to deform and propel a portion of the treatment
substance from the implantable reservoir to the distal end of the
delivery tube for delivery to the recipient.
15. The method of claim 14, wherein the resiliently flexible
portion comprises part of the implantable reservoir, and wherein
receiving the user applied external force comprises: receiving a
user applied external force delivered to a resiliently flexible
portion of the implantable reservoir.
16. The method of claim 15, wherein the implantable reservoir is
fluidically coupled to the delivery tube via a check valve, and
wherein the user applied external force propels a portion of the
treatment substance through the check valve into the delivery tube
for delivery to the recipient.
17. The method of claim 14, wherein the apparatus comprises an
expansion tube disposed between the implantable reservoir and the
delivery tube, and wherein receiving the user applied external
force delivered to the at least one resiliently flexible portion
comprises: receiving a user applied external force delivered to a
resiliently flexible portion of the expansion tube.
18. The method of claim 14, wherein the proximal end of the
delivery tube is fluidically coupled to the implantable reservoir
via a magnetically activated check valve, and wherein the method
further comprises: opening the magnetically activated check valve
in response to positioning of an external magnet in a proximity to
the magnetically activated check valve.
19. The method of claim 14, wherein the apparatus comprises an
implantable flushing reservoir configured to be selectively
fluidically coupled to the delivery tube, and wherein the method
further comprises: receiving, through the skin of the recipient, a
user applied external force delivered to at least one resiliently
flexible portion of the implantable flushing reservoir, wherein the
user applied external force causes the at least one resiliently
flexible portion of the of the implantable flushing reservoir to
deform; and in response to the user applied external force,
transferring a portion of a flushing solution disposed in the
implantable flushing reservoir to the delivery tube.
20. The method of claim 14, wherein the apparatus comprises a
delivery device disposed at the distal end of the delivery tube,
and wherein the method comprises: administering the treatment
substance to a target location within the recipient via the
delivery device.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation application of U.S.
patent application Ser. No. 16/547,952, filed Aug. 22, 2019, which
is a continuation application of U.S. patent application Ser. No.
15/450,112, filed Mar. 6, 2017, which is a continuation application
of U.S. patent application Ser. No. 14/315,825, filed Jun. 26,
2014, now U.S. Pat. No. 9,616,207. The contents of these
applications are hereby incorporated by reference herein in the
entirety.
BACKGROUND
Field of the Invention
[0002] The present invention relates generally to delivery of
treatment substances to the ear of an implantable auditory
prosthesis recipient.
Related Art
[0003] Individuals suffer from a variety of hearing problems, such
as tinnitus, Meniere's disease, vertigo, hearing loss, etc. Hearing
loss, for example, which may be due to many different causes, is
generally of two types, conductive and/or sensorineural. Conductive
hearing loss occurs when the normal mechanical pathways of the
outer and/or middle ear are impeded, for example, by damage to the
ossicular chain or ear canal. Sensorineural hearing loss occurs
when there is damage to the inner ear, or to the nerve pathways
from the inner ear to the brain.
[0004] Individuals who suffer from conductive hearing loss
typically have some form of residual hearing because the hair cells
in the cochlea are undamaged. As such, individuals suffering from
conductive hearing loss typically receive an auditory prosthesis
that generates motion of the cochlea fluid. Such auditory
prostheses include, for example, acoustic hearing aids, bone
conduction devices, and direct acoustic stimulators.
[0005] In many people who are profoundly deaf, however, the reason
for their deafness is sensorineural hearing loss. Those suffering
from some forms of sensorineural hearing loss are unable to derive
suitable benefit from auditory prostheses that generate mechanical
motion of the cochlea fluid. Such individuals can benefit from
implantable auditory prostheses that stimulate nerve cells of the
recipient's auditory system in other ways (e.g., electrical,
optical and the like).
SUMMARY
[0006] In one aspect, an apparatus is provided. The apparatus
comprises an implantable reservoir configured to have a treatment
substance disposed therein, an implantable delivery tube having a
proximal end fluidically coupled to the reservoir and a distal end
positioned adjacent a target location within a recipient, and a
passive activation mechanism configured to transfer a portion of
the treatment substance in the reservoir to the delivery tube for
delivery to the target location.
[0007] In another aspect, an apparatus is provided. The apparatus
comprises an at least partially implantable elongate delivery tube
configured to have a treatment substance disposed therein, wherein
the delivery tube is configured to be positioned in a recipient
such that a distal end of the delivery tube is adjacent a target
location within the recipient, and a delivery device disposed at
the distal end of the delivery tube configured to transfer the
treatment substance in the delivery tube to the target
location.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] Embodiments of the present invention are described herein in
conjunction with the accompanying drawings, in which:
[0009] FIG. 1 is a schematic diagram illustrating the anatomy of a
recipient at a location in which a delivery system herein may be
implanted;
[0010] FIG. 2A illustrates a delivery system in accordance with
embodiments presented herein implanted in a recipient;
[0011] FIG. 2B illustrates a first portion of the delivery system
of FIG. 2A;
[0012] FIG. 2C illustrates a cross-sectional view of a second
portion of the delivery system of FIG. 2A;
[0013] FIGS. 3A and 3B illustrate a reservoir in accordance with
embodiments presented herein;
[0014] FIG. 4 illustrates another reservoir implanted in a
recipient's middle ear cavity in accordance with embodiments of the
present invention;
[0015] FIG. 5A illustrates a delivery system in accordance with
embodiments presented herein that utilizes an external magnet to
force a treatment substance from a reservoir;
[0016] FIG. 5B illustrates another delivery system in accordance
with embodiments presented herein that utilizes an external magnet
to force a treatment substance from a reservoir;
[0017] FIG. 6 illustrates another delivery system in accordance
with embodiments presented herein;
[0018] FIG. 7 illustrates another delivery system in accordance
with embodiments presented herein;
[0019] FIG. 8A illustrates a further delivery system in accordance
with embodiments presented herein;
[0020] FIG. 8B illustrates a first portion of the delivery system
of FIG. 8A;
[0021] FIG. 8C illustrates another portion of the delivery system
of FIG. 8A;
[0022] FIG. 9 illustrates another delivery system in accordance
with embodiments presented herein;
[0023] FIGS. 10A-10C illustrate arrangements for securing
components of a delivery system within a recipient;
[0024] FIG. 11 illustrates a delivery tube positioning mechanism in
accordance with embodiments presented herein;
[0025] FIGS. 12A and 12B illustrate a delivery tube in accordance
with embodiments presented herein;
[0026] FIGS. 13A and 13B illustrate another delivery tube in
accordance with embodiments presented herein;
[0027] FIG. 14 is a schematic diagram illustrating another delivery
system in accordance with embodiments presented herein; and
[0028] FIG. 15 is a schematic diagram illustrating a further
delivery system in accordance with embodiments presented
herein.
DETAILED DESCRIPTION
[0029] Presented herein are implantable systems and methods for
long-term delivery of substances (e.g., biological or bioactive),
chemicals, pharmaceutical agents, nanoparticles, ions, drugs, etc.
(generally and collectively referred to herein as "treatment
substance") to a target location within a recipient of a treatment
substance delivery system and/or implantable auditory (hearing)
prosthesis (e.g, bone conduction device, direct acoustic
stimulator, cochlear implant, etc.), The target location may be,
for example, the recipient's middle ear, inner ear, vestibular
system, round window, oval window, cochleostomy, etc. Before
describing illustrative embodiments of the treatment substance
delivery systems and methods presented herein, a brief description
of the human anatomy of a recipient's ear is first provided with
reference to FIG. 1.
[0030] As shown in FIG. 1, a recipient's ear comprises an outer ear
101, a middle ear 105 and an inner ear 107. In a fully functional
ear, outer ear 101 comprises an auricle 110 and an ear canal 102.
An acoustic pressure or sound wave 103 is collected by auricle 110
and channeled into and through ear canal 102. Disposed across the
distal end of ear canal 102 is a tympanic membrane 104 which
vibrates in response to sound wave 103. This vibration is coupled
to oval window or fenestra ovalis 112, which is adjacent round
window 121, through the bones of the middle ear 105. The bones of
the middle ear 105 comprise the malleus 108, the incus 109 and the
stapes 111, collectively referred to as the ossicles 106. The
ossicles 106 are positioned in the middle ear cavity 113 and serve
to filter and amplify the sound wave 103, causing oval window 112
to articulate (vibrate) in response to the vibration of tympanic
membrane 104. This vibration of the oval window 112 sets up waves
of fluid motion of the perilymph within cochlea 140. Such fluid
motion, in turn, activates tiny hair cells (not shown) inside of
cochlea 140. Activation of the hair cells causes appropriate nerve
impulses to be generated and transferred through the spiral
ganglion cells (not shown) and auditory nerve 114 to the brain
(also not shown) where they are perceived as sound
[0031] The human skull is formed from a number of different bones
that support various anatomical features. Illustrated in FIG. 1 is
the temporal bone 115 which is situated at the side and base of the
recipient's skull 124. For ease of reference, the temporal bone 115
is referred to herein as having a superior portion 118 and a
mastoid portion 120. The superior portion 118 comprises the section
of the temporal bone 115 that extends superior to the auricle 110.
That is, the superior portion 118 is the section of the temporal
bone 115 that forms the side surface of the skull. The mastoid
portion 120, referred to herein simply as the mastoid 120, is
positioned inferior to the superior portion 118. The mastoid 120 is
the section of the temporal bone 115 that surrounds the middle ear
105.
[0032] As shown in FIG. 1, semicircular canals 125 are three
half-circular, interconnected tubes located adjacent cochlea 140.
Vestibule 129 provides fluid communication between semicircular
canals 125 and cochlea 140. The three canals are the horizontal
semicircular canal 126, the posterior semicircular canal 127, and
the superior semicircular canal 128. The canals 126, 127 and 128
are aligned approximately orthogonally to one another.
Specifically, horizontal canal 126 is aligned roughly horizontally
in the head, while the superior 128 and posterior canals 127 are
aligned roughly at a 45 degree angle to a vertical through the
center of the individual's head.
[0033] Each canal is filled with a fluid called endolymph and
contains a motion sensor with tiny hairs (not shown) whose ends are
embedded in a gelatinous structure called the cupula (also not
shown). As the orientation of the skull changes, the endolymph is
forced into different sections of the canals. The hairs detect when
the endolymph passes thereby, and a signal is then sent to the
brain. Using these hair cells, horizontal canal 126 detects
horizontal head movements, while the superior 128 and posterior 127
canals detect vertical head movements.
[0034] It may be advantageous to have an extended delivery solution
for use in the delivery of treatment substances to a target
location of a recipient. In general, extended treatment substance
delivery refers to the delivery of treatment substances over a
period of time (e.g., continuously, periodically, etc.), The
extended delivery may be activated during or after surgery and can
be extended as long as is needed. The period of time may not
immediately follow the initial implantation of the auditory
prosthesis. As such, embodiments of the present invention are
directed to different features that facilitate extended delivery of
treatment substances. More specifically, certain embodiments are
directed to passive actuation (drive) mechanisms that eliminate the
need for an implanted active (i.e., powered) pump and power source
to deliver treatment substances to a target location. Additional
embodiments are directed to optional fixation mechanisms that
retain various components of a delivery system at a selected
implanted location. Further embodiments are directed to accretion
prevention (anti-accretion) mechanisms that prevent the buildup of
undelivered particles within the system that can inhibit subsequent
delivery of treatment substances.
[0035] FIG. 2A illustrates an implantable delivery system 200
having a passive actuation mechanism in accordance with embodiments
presented herein. The delivery system 200 is sometimes referred to
herein as an inner ear delivery system because it is configured to
deliver treatment substances to the recipient's inner ear (e.g.,
the target location is the interior of the recipient's cochlea
140). FIG. 2B illustrates a first portion of the delivery system
200, while FIG. 2C is a cross-sectional view of a second portion of
the delivery system 200.
[0036] Delivery system 200 of FIGS. 2A-2C comprises a reservoir
202, a valve 204, a delivery tube 206, and a delivery device 208
(FIG. 2C). The delivery system 200 may include, or operate with, an
external magnet 210. For ease of illustration, the delivery system
200 is shown separate from any implantable auditory prostheses.
However, it is to be appreciated that the delivery system 200 could
be used with, for example, cochlear implants, direct acoustic
stimulators, bone conduction devices, etc. In such embodiments, the
implantable components (e.g., reservoir, valve, delivery tube,
etc.) of delivery system 200 could be separate from or integrated
with the other components of the implantable auditory
prosthesis.
[0037] In the embodiment of FIGS. 2A-2C, the reservoir 202 is
positioned within the recipient underneath a portion of the
recipient's skin/muscle/fat, collectively referred to herein as
tissue 219. The reservoir 202 may be positioned between layers of
the recipient's tissue 219 or may be adjacent to a subcutaneous
outer surface 229 of the recipient's skull. For example, the
reservoir 202 may be positioned in a surgically created pocket at
the outer surface 229 (i.e., adjacent to a superior portion 118 of
the temporal bone 115).
[0038] The reservoir 202 is, prior to or after implantation, at
least partially filled with a treatment substance for delivery to
the inner ear 107 of the recipient. The treatment substance may be,
for example, in a liquid form, a gel form, and/or comprise
nanoparticles or pellets. In certain arrangements, the treatment
substance may initially be in a crystalline/solid form that is
subsequently dissolved. For example, a reservoir could include two
chambers, one that comprises a fluid (e.g., artificial perilymph or
saline) and one that comprises the crystalline/solid treatment
substance. The fluid may be mixed with the crystalline/solid
treatment substance to form a fluid or gel treatment substance that
may be subsequently delivered to the recipient.
[0039] In certain embodiments, the reservoir 202 includes a needle
port (not shown) so that the reservoir 202 can be refilled via a
needle injection through the skin. In other embodiments, the
reservoir 202 may be explanted and replaced with another reservoir
that is, prior to or after implantation, at least partially filled
with a treatment substance. In accordance with certain embodiments,
the reservoir 202 may have a preformed shape and the reservoir is
implanted in this shape. In other embodiments, the reservoir 202
may have a first shape that facilitates implantation and a second
shape for use in delivering treatment substances to the recipient.
For example, the reservoir 202 may have a rolled or substantially
flat initial shape that facilitates implantation. The reservoir 202
may then be configured to expand after implantation. Such
embodiments may be used, for example, to insert the reservoir
through a tympanostomy into the middle ear or ear canal, through an
opening in the inner ear, or to facilitate other minimally invasive
insertions.
[0040] The delivery tube 206 includes a proximal end 212 and a
distal end 214. The proximal end 212 of the delivery tube 206 is
fluidically coupled to the reservoir 202 via the valve 204. As
shown in FIG. 2C, the distal end 214 of the delivery tube 206 is
fluidically coupled to the recipient's round window 121. A delivery
device 208 disposed within the distal end 214 of the delivery tube
206 is positioned abutting the round window 121. As described
further below, the delivery tube 206 may be secured within the
recipient so that the distal end 214 remains located adjacent to
the round window 121.
[0041] FIGS. 2A-2C illustrate embodiments that utilize a passive
actuation mechanism to produce a pumping action to transfer a
treatment substance from the reservoir 202 to the delivery device
208 at the distal end 214 of the delivery tube 206. More
specifically, in these illustrative embodiments, the reservoir 202
is compressible in response to an external force 216. That is, at
least one part or portion of the reservoir 202, such as wall 220 or
a portion thereof, is formed from a resiliently flexible material
that is configured to deform in response to application of the
external force 216. In certain embodiments, the positioning of the
reservoir 202 adjacent the superior portion 118 of the mastoid 115
provides a rigid surface that counters the external force 216. As a
result, a pressure change occurs in the reservoir 202 so as to
propel (push) a portion of the treatment substance out of the
reservoir through valve 204.
[0042] FIGS. 2A and 2B illustrate a specific arrangement in which
the reservoir 202 includes a resiliently flexible wall 220. It is
to be appreciated that the reservoir 202 may be formed from various
resiliently flexible parts and rigid parts. It is also to be
appreciated that the reservoir 202 may have a variety of shapes and
sizes (e.g., cylindrical, square, rectangular, etc.) or other
configurations. For example, in one embodiment the reservoir 202
could further include a spring mounted base that maintains a
pressure in the reservoir 202 until the reservoir is substantially
empty. Other mechanisms for maintaining a pressure in the reservoir
may be used in other arrangements.
[0043] In certain embodiments, the external force 216 is applied
manually using, for example, a user's finger. The user (e.g.,
recipient, clinician, caregiver, etc.) may press on the tissue 219
adjacent to the reservoir 202 to create the external force 216. In
certain embodiments, a single finger press may be sufficient to
propel the treatment substance through valve 204. In other
embodiments, multiple finger presses may be used to create a
pumping action that propels the treatment substance from the
reservoir 202.
[0044] In other embodiments, the external force 216 is applied
through a semi-manual method that uses an external actuator 217
(FIG. 2B). That is, the external actuator 217 may be pressed onto
the soft tissue 219 under which the reservoir 202 is located. The
movement (e.g., oscillation/vibration) of the actuator 217 deforms
the reservoir 202 to create the pumping action that propels the
treatment substance out of the reservoir.
[0045] In certain embodiments, internal and/or external magnets
and/or magnetic materials may be used in the arrangements of FIGS.
2A and 2B to ensure that the actuator 217 applies force at an
optimal location of the reservoir 202. For example, the reservoir
202 may include a magnetic positioning member 213 located at or
near an optimal location for application of an external force from
the actuator 217. The actuator 217 may include a magnet 215
configured to magnetically mate with the magnetic positioning
member 213. As such, when actuator 217 is properly positioned, the
magnet 215 will mate with the magnetic positioning member 213 and
the force from the actuator 217 will be applied at the optimal
location.
[0046] In other embodiments, a remote control, remotely placed
actuator (subcutaneous or otherwise) may be alternatively used. For
example, in a further arrangement, the implant includes implanted
electronics 253 (shown using dotted lines in FIG. 2B). These
implanted electronics 253 may be configured to, for example,
control the valve 204 and/or include an actuation mechanism that
can force treatment substance from the reservoir 202. In certain
embodiments, the implanted electronics 253 may be powered and/or
controlled through a transcutaneous link (e.g., RF link). As such,
the implanted electronics 253 may include or be electrically
connected to an RF coil, receiver/transceiver unit, etc.
[0047] In accordance with certain embodiments, the implanted
electronics 253 may include or be connected to a sensor that is
used, at least in part, to assist in control of delivery of the
treatment substance to the recipient. For example, a sensor (e.g.,
a temperature sensor, a sensor to detect infection or bacteria
growth, etc.) may provide indications of when a treatment substance
should be delivered and/or when delivery should be ceased for a
period of time. A sensor may also be configured to determine an
impact of the treatment substance on the recipient (e.g., evaluate
effectiveness of the treatment substance).
[0048] As noted, the treatment substance is released from the
reservoir 202 through the valve 204. The valve 204 may be a check
valve (one-way valve) that allows the treatment substance to pass
there through in one direction only. This assures that released
treatment substances do not back-flow into the reservoir 202. In
certain embodiments, the valve 204 is a valve that is configured to
open in response to the pressure change in the reservoir 202 (e.g.,
a ball check valve, diaphragm check valve, swing check valve or
tilting disc check valve, etc.). The valve 204 may be a stop-check
valve that includes an override control to stop flow regardless of
flow direction or pressure. That is, in addition to closing in
response to backflow or insufficient forward pressure (as in a
normal check valve), a stop-check value can also be deliberately
opened or shut by an external mechanism, thereby preventing any
flow regardless of forward pressure. The valve 204 may be a
stop-check value that is controlled by an external electric or
magnetic field generated by, for example, the external magnet 210,
an electromagnet, etc. In the embodiments, of FIGS. 2A and 2B, the
valve is responsive to a magnetic field generated by external
magnet 210. As such, the valve 204 will temporarily open when the
external magnet 210 is positioned in proximity to the valve 204 and
will close when the external magnet 210 is removed from the
proximity of the valve 204. In certain embodiments, variable magnet
strengths of external magnets may be used to control the dosage of
the treatment substance. Additionally, an electromagnet may be used
in place of the external magnet 210.
[0049] The use of a stop-check valve may prevent unintended dosing
of the treatment substance when, for example, an accidental
external force acts on the reservoir 202. The reservoir 202 is
formed such that an increase in pressure of the reservoir 202
without an accompanying treatment substance release will not damage
(i.e., rupture) the reservoir.
[0050] It is to be appreciated that the use of a magnetically
activated stop-check valve is merely exemplary and that other types
of valves may be used in alternative embodiments. For example, in
alternative embodiments the valve 204 may be actuated (i.e.,
opened) in response to an electrical signal (e.g., piezoelectric
valve). The electrical signal may be received from a portion of an
auditory prosthesis (not shown) that is implanted with the delivery
system 200 or the electrical signal may be received from an
external device (e.g., an RF actuation signal received from an
external sound processor, remote control, etc.). In other
embodiments, manually applied (e.g., finger) force be also able to
open the valve 204.
[0051] Once the treatment substance is released through valve 204,
the treatment substance flows through the delivery tube 206 to the
delivery device 208. The delivery device 208 operates as a transfer
mechanism to transfer the treatment substance from the delivery
tube 206 to the round window 121. The treatment substance may then
enter the cochlea 140 through the round window 121 (e.g., via
osmosis). The delivery device 208 may be, for example, a wick, a
sponge, permeating gel (e.g., hydrogel), etc.
[0052] In accordance with further embodiments presented herein, the
reservoir 202 may include a notification mechanism that transmits a
signal or notification indicating that the reservoir 202 is
substantially empty and/or needs refilled. For example, one or more
electrode contacts (not shown) may be present and become
electrically connected when the reservoir is substantially empty.
Electronic components associated with or connected to the reservoir
202 may accordingly transmit a signal indicating that reservoir
needs filled or replaced.
[0053] FIGS. 2A-2C illustrate a specific example in which the round
window 121 is the target location. As noted above, the round window
121 is an exemplary target location and other target locations are
possible in accordance with embodiments presented herein.
[0054] FIGS. 2A-2C illustrate an embodiment in which the reservoir
202 is positioned adjacent to the outer surface 229 of the
recipient's skull so that an external force may be used to propel
the treatment substance from the reservoir. FIGS. 3A and 3B
illustrate another embodiment where an external force is not
utilized to propel the treatment substance from the reservoir 202.
More specifically, in the embodiments of FIGS. 3A-3B the reservoir
202 is positioned between a recipient's muscle 330 (e.g.,
temporalis (temporal muscle), jaw, etc.) and hard tissue 332 (e.g.,
bone, teeth, etc.). As shown in FIG. 3A, the muscle 330 may be in a
relaxed state where little or no pressure is placed on the
reservoir 202. As shown in FIG. 3B, the muscle 330 may
alternatively be in a contracted state that compresses the
reservoir 202. The compression of the reservoir 202 in response to
the muscle contraction propels the treatment substance from the
reservoir 202 into the delivery tube 206 via the valve 204. In
certain circumstances, the muscle 330 may be contracted through
mastication. As noted, the valve 204 may be a check valve or a
stop-check valve (e.g., a magnetically operated valve).
[0055] FIG. 4 illustrates a further embodiment where an external
force may not be needed to propel a treatment substance from an
implantable reservoir. More specifically, in delivery system 400 of
FIG. 4, a reservoir 402 is positioned in the recipient's middle ear
cavity 113. The reservoir 402 is, at least in part, formed from a
resiliently flexible material that is deformable in response to
pressurization of the middle ear cavity 113. FIG. 4 illustrates an
example in which the reservoir 402 includes first and second
opposing walls 420(1) and 420(2) that may deform in response to
pressurization of the middle ear cavity 113. Deformation of the
walls 420(1) and 420(2) pressurizes the interior of the reservoir
402 so as to propel the treatment substance through the valve 404
and into the delivery tube 406. Similar to the embodiments of FIGS.
2A-2B, the valve 404 may be a check valve or a stop-check valve
(e.g., a magnetically operated valve).
[0056] In certain examples, ear equalization techniques can be used
to pressurize the middle ear cavity 113 and deform the flexible
reservoir 402. For example, the Valsalva maneuver (i.e., where the
recipient pinches his/her nostrils closed and blows gently through
the nose), the Frenzel maneuver (i.e., where the recipient performs
a gentle Valsalva maneuver by breathing against pinched nostrils
and swallowing at the same time), etc. may be used.
[0057] FIG. 4 illustrates an embodiment in which the reservoir 402
includes first and second opposing walls 420(1) and 420(2) that may
deform in response to pressurization of the middle ear cavity 113.
The reservoir 402 is secured within the middle ear cavity such that
the pressure may act on both walls 420(1) and 420(2). In an
alternative embodiment, the reservoir 402 may secured such that one
wall of the reservoir 402 abuts hard tissue. In such embodiments,
the reservoir wall that abuts the hard tissue may be compressible
or substantially rigid.
[0058] FIG. 5A illustrates an embodiment where magnetic attraction
is used to force a treatment substance from an implantable
reservoir. More specifically, in the embodiment of FIG. 5A a
magnetic element 534 is implanted abutting the outer surface 229 of
the recipient's skull. The magnetic element 534 may be formed from
a ferromagnetic or ferrimagnetic material. The ferromagnetic or
ferrimagnetic material may be magnetized (i.e., a permanent magnet)
or non-magnetized. FIG. 5A illustrates a specific embodiment in
which the magnetic element 534 is a permanent magnet. The magnetic
element 534 may be (optionally) secured to the superior portion 118
of recipient's temporal bone 115 using, for example, a bone screw
(not shown) or another fixation mechanism (e.g., adhesive).
Alternatively, the magnetic element 534 may be held in place by the
recipient's tissue 219.
[0059] As shown, the reservoir 202 is implanted so as to abut an
externally-facing surface 525 of the magnetic element 534 (i.e., a
surface facing away from the recipient's temporal bone 115). The
reservoir 202 may be secured to the magnetic element 534 and/or the
recipient's temporal bone using one or more fixation mechanisms
described further below or may be held in place by the recipient's
tissue 219.
[0060] In the embodiment of FIG. 5A, an external magnet 536 may be
placed adjacent to the recipient's tissue 219 that at least
partially covers the reservoir 202. The poles of the external
magnet 536 and the magnetic element 534 are oriented so that the
external magnet 536 and the magnetic element 534 will be
magnetically attracted to one another when in proximity to one
another. As shown by arrows 538 in FIG. 5A, the mutual attraction
between the external magnet 536 and the magnetic element 534
compresses the recipient's tissue 219 adjacent to the reservoir
202. The compression of the tissue, in turn, compresses the wall
220 of the reservoir 220. The positioning of the reservoir 202
abutting the magnetic element 435 and the superior portion 118 of
the mastoid 115 provides a rigid surface that counters the
compression of the tissue 219. As a result, a pressure change
occurs in the reservoir 202 so as to propel a portion of the
treatment substance out of the reservoir through valve 204.
[0061] As noted, the valve 204 may be a check valve or a stop-check
valve (e.g., a magnetically operated valve). In embodiments in
which the valve 204 is a magnetically operated valve, the external
magnet 536 may be configured so as to compress the reservoir 202
and additionally open valve 204.
[0062] The magnetic element 534 and external magnet 536 may have a
variety of shapes and sizes (e.g., cylindrical, square,
rectangular, etc.). In certain embodiments, the magnetic element
534 and external magnet 536 have corresponding generally annular
shapes to enhance the alignment of the magnetic elements with one
another.
[0063] FIG. 5B illustrates another embodiment where magnetic
attraction is used to force a treatment substance from an
implantable reservoir. More specifically, in the embodiment of FIG.
5B a reservoir 502 comprises a first end plate 513 connected to a
second plate 515 by a substantially flexible outer wall 519. The
end plates 513 and 515 may be, for example, circular, oval, square,
rectangular, etc. so as to, along with flexible outer wall 519,
form a closed body in which a treatment substance may be disposed.
One or both of the end plates 513 and 515 may be formed from
ferromagnetic or ferrimagnetic material (magnetized or
non-magnetized) such that when an external magnet 537 is in
proximity to the reservoir 502, the treatment substance may be
forced through valve 204. For example, in one such embodiment the
end plates 513 and 515 may be configured such that the presence of
the magnet 537 causes plate 513 to be forced away from the magnet
537 (as shown by arrows 521), while the end plate 515 is pulled
towards the magnet 537 (as shown by arrows 523). This "squeezing"
action produced by the presence of external magnet 537 forces the
treatment substance through valve 204.
[0064] FIGS. 2A through 5B illustrate embodiments in which drugs
that are forced from an implantable reservoir pass through a valve
and directly into a delivery tube. FIG. 6 illustrates an embodiment
where a secondary reservoir 640 is added to enable extended
treatment substance release. More specifically, in the embodiment
of FIG. 6, when the treatment substance is released from reservoir
202, the treatment substance passes through valve 204 and into a
connector tube 642. The distal end 643 of the connector tube 642 is
connected to the secondary reservoir 640 such that application of
the external force 216 propels the treatment substance from
reservoir 202 into the secondary reservoir 640. A valve 644 at the
output of the secondary reservoir 640 may be configured to release
the treatment substance from the secondary reservoir to the
delivery tube 206 at a predetermined rate (e.g., at certain time
periods). As such, the arrangement of FIG. 6 can utilize the
secondary reservoir 640 to deliver the treatment substance to the
delivery device 208 (FIG. 2C) over a period of time without the
need for application of additional external forces 216.
[0065] FIG. 6 illustrates the use of a secondary reservoir and a
primary reservoir positioned adjacent to the outer surface 229 of
the recipient's skull. It is to be appreciated that a secondary
reservoir may also be used in other embodiments presented herein
(e.g., with a primary reservoir positioned in the middle ear
cavity).
[0066] FIG. 7 illustrates another embodiment where the external
force is applied to a section of tubing rather than a reservoir.
More specifically, FIG. 7 illustrates a delivery system 700 that
comprises a reservoir 702, a valve 704, an expansion tube 705, a
delivery tube 706, a secondary valve 744, and a delivery device
(not shown). The delivery system 700 may include, or operate with,
an external magnet 710.
[0067] In the embodiment of FIG. 7, the reservoir 702 and the
expansion tube 705 are positioned underneath the recipient's tissue
219 adjacent to outer surface 229 of the recipient's skull. The
reservoir 702 is at least partially filled with a treatment
substance for delivery to the inner ear 107 of the recipient. The
reservoir 702 may include a needle port (not shown) so that the
reservoir can be refilled via a needle injection through the skin
or the reservoir 702 may be explanted and replaced with another
reservoir that is configured to be at least partially filled with a
treatment sub stance.
[0068] The expansion tube 705 is a tubing section formed from a
resiliently flexible (e.g., elastomer) element configured to
compress in response to application of an external force 216
applied, for example, manually or semi-manually as described above.
The positioning of the expansion tube 705 adjacent the superior
portion 118 of the mastoid 115 provides a rigid surface that
counters the external force 216. As a result, that application and
subsequent removal of the external force 216 causes rapid
pressurization and depressurization of the expansion tube 705 so as
to pull the treatment substance from reservoir 702 through the
valve 704. As a result, the expansion tube 705 expands as it is
substantially or partially filled with the treatment substance.
[0069] It is to be appreciated that the positioning of expansion
tube 705 adjacent the superior portion 118 of the mastoid 115 is
merely illustrative. The expansion tube 705 may be positioned to
other natural or surgical implanted semi-rigid elements so as to
enable rapid pressurization and depressurization of the expansion
tube 705.
[0070] The expansion tube 705 may fill up to a certain volume in
response to the repeated application and removal of the external
force 216. The valve 744 at the output of the expansion tube 705
may be configured to release the treatment substance from the
secondary reservoir to the delivery tube 706 at a predetermined
rate (e.g., at certain time periods). As such, the arrangement of
FIG. 7 can utilize the expansion tube 705 to deliver the treatment
substance to the delivery device over a period of time without the
need for application of additional external forces 216.
[0071] As noted, the treatment substance is released from the
reservoir 702 through the valve 704. The valve 704 may be a check
valve that allows the treatment substance to pass there through in
one direction only. This assures that released treatment substances
do not back-flow into the reservoir 702. In certain embodiments,
the valve 704 is a valve that is configured to open in response to
the pressure change in the expansion tube 705. In certain
embodiments, the valve 704 is a stop-check valve that includes an
override control to stop flow regardless of flow direction or
pressure. For example, the valve 704 may be a stop-check value that
is controlled by the external magnet 710. In such embodiments, the
valve 704 will temporarily open when the external magnet 710 is
positioned in proximity to the valve 704 and will close when the
external magnet 710 is removed from the proximity of the valve 704.
The use of a stop-check valve may prevent unintended dosing of the
treatment substance when, for example, an accidental external force
acts on the expansion tube 705.
[0072] It is to be appreciated that the use of magnetically
activated stop-check valve is merely exemplary and that other types
of valves may be used in alternative embodiments. For example, in
alternative embodiments the valve 704 may be actuated (i.e.,
opened) in response to an electrical signal. The electrical signal
may be received from a portion of an auditory prosthesis (not
shown) that is implanted with the delivery system 700 or the
electrical signal may be received from an external device (e.g., an
RF actuation signal received from an external sound processor,
remote control, etc.).
[0073] FIGS. 2A-7 illustrate embodiments that utilize an
implantable reservoir and a passive actuation mechanism to transfer
treatment substances from the reservoir to a target location. In
alternative embodiments, treatment substances are delivered to a
recipient's middle ear/inner ear using a substantially external
system where the reservoir and actuation unit (e.g., pump) need not
be implanted in the recipient. More specifically. FIGS. 8A-8C
illustrate a delivery system 800 comprising an external component
850, a delivery tube 806, and delivery device 808. The external
component 850 is a behind-the-ear component that is configured to
be worn on the outer ear 101 of the recipient.
[0074] As shown in FIG. 8B, the external component 850 comprises a
reservoir 802 that is configured to be at least partially filled
with a treatment substance. The external component 850 also
comprises a valve 804 (e.g., check valve), a pump 852 and a power
source (e.g., battery) 854. In operation, the pump 852 propels the
treatment substance in the reservoir 802 through the valve 804 and
into the delivery tube 806.
[0075] The delivery tube 806 has a proximal end 812 (FIG. 8B) that
is fluidically coupled to the valve 804, and a distal end 814 (FIG.
8C) that is fluidically coupled to the round window 121. As shown
in FIGS. 8A and 8C, the delivery tube 806 extends from the external
component 850 and into the recipient's ear canal 102. The delivery
tube 806 also extends through the recipient's tympanic membrane 104
to the round window 121. In particular, the delivery tube 806
passes through a surgically formed opening within the tympanic
membrane 104. A surgically placed grommet 856 seals the opening in
the tympanic membrane 104 around the delivery tube.
[0076] Once the treatment substance is released through valve 804,
the treatment substance flows through the delivery tube 806 to the
delivery device 808 (passing through the ear canal 102 and the
tympanic membrane 104). The delivery device 808 operates as a
transfer mechanism to transfer the treatment substance from the
delivery tube 806 to the round window 121. The treatment substance
may then enter the cochlea 140 through the round window 121 (e.g.,
via osmosis). The delivery device 808 may be, for example, a wick,
a sponge, permeating gel (e.g., hydrogel), etc.
[0077] External components, such as behind-the-ear components, are
used with a number of implantable auditory prostheses. It is to be
appreciated that the external component 850 of FIGS. 8A and 8B may
also include the components of an external component used with an
implantable auditory prosthesis (e.g., sound processor, sound input
element, etc.). That is, external component 850 may be integrated
with the components of an external component of an implantable
auditory prosthesis.
[0078] FIG. 9 illustrates another delivery system 900 comprising an
external component 950, a delivery tube 906, and a delivery device
(not shown). The external component 950 is an in-the-ear component
positioned in the pinna 110 or ear canal 102 of the recipient.
[0079] The external component 950 comprises a reservoir 902 that is
configured to be at least partially filled with a treatment
substance. The external component 950 also comprises a valve 904
(e.g., check valve), a pump 952, and a power source 954. In
operation, the pump 952 propels the treatment substance in the
reservoir 902 through the valve 904 and into the delivery tube
906.
[0080] The delivery tube 906 has a proximal end 912 that is
fluidically coupled to the valve 904 and a distal end (not shown)
that is fluidically coupled to the round window 121. The delivery
tube 906 extends from the external component 950 through the
recipient's tympanic membrane 104 to the round window 121. In
particular, the delivery tube 906 passes through a surgically
formed opening within the tympanic membrane 104. A surgically
placed grommet 956 seals the opening in the tympanic membrane 104
around the delivery tube.
[0081] Once the treatment substance is released through valve 904,
the treatment substance flows through the delivery tube 906 to a
delivery device (not shown) by passing through the tympanic
membrane 104. The delivery device may be substantially similar to
delivery device 808 of FIG. 8 and operates as a transfer mechanism
to transfer the treatment substance from the delivery tube 906 to
the round window 121.
[0082] Delivery systems in accordance with embodiments presented
herein are intended for delivery of treatment substances to a
target location within a recipient. As noted, the target location
may be, for example, the recipient's middle ear, inner ear, round
window, oval window, through a cochleostomy, on/at a cochleostomy,
etc. In certain examples, the target location may be a portion of
the inner ear that enables the treatment substance to travel to a
further location such as, for example, the auditory brainstem or
brain. In accordance with certain arrangements, the delivery
systems may include one or more fixation mechanisms that retain
various components of the delivery systems at a selected implanted
location to ensure that the treatment substance is properly
delivered to the target location. FIGS. 10A-13B illustrate fixation
mechanisms that may be used in accordance with embodiments
presented herein.
[0083] FIGS. 10A-10D illustrate mechanisms for securing components
of an implantable delivery system to tissue of a recipient. More
specifically, FIG. 10A illustrates a reservoir 1002(A) that
includes first and second anchor loops 1057(1) and 1057(2). The
anchor loops 1057(1) and 1057(2) may be integrated with the
reservoir 1002 or attached to the reservoir using, for example, a
bonding agent (e.g., bone cement or other biocompatible adhesive).
In certain embodiments, the anchor loops 1057(1) and 1057(2) are
formed from a resiliently flexible material (e.g., a similar
material used to form the reservoir 1002(A)). In other embodiments,
the anchor loops 1057(1) and 1057(2) are formed from a
substantially rigid material (e.g., titanium).
[0084] The anchor loops 1057(1) and 1057(2) each include an
aperture 1058. The reservoir 1002 is configured to be positioned
adjacent to the recipient's tissue. Bone screws 1059 or other
fasteners may then be inserted through the apertures 1058 and into
the tissue. In this way, the bone screws secure the reservoir
1002(A) in position. In alternative embodiments, the anchor loops
1057(1) and 1057(2) may be replaced with pads or other members that
enable the reservoir 1002(A) to be secured to the recipient using,
for example, a bonding agent (e.g., bone cement or other
biocompatible adhesive), sutures, etc.
[0085] FIG. 10B illustrates another reservoir 1002(B) with a first
fastening bracket 1060(1) and a second fastening bracket 1060(2).
The first fastening bracket 1060(1) includes an anchor loop 1061(1)
at a first end of the bracket and an anchor loop 1062(1) at a
second end of the bracket. The second fastening bracket 1060(2)
includes an anchor loop 1061(2) at a first end of the bracket and
an anchor loop 1062(2) at a second end of the bracket. Each of the
anchor loops 1061(1), 1061(2), 1062(1), and 1062(2) include an
aperture 1063.
[0086] The reservoir 1002(B) is configured to be positioned
adjacent to the recipient's tissue. The fastening brackets 1060(1)
and 1060(2) are configured to fit around the reservoir 1002(B) and
bone screws 1059 (FIG. 10A) or other fasteners may then be inserted
through the apertures 1058 and into the tissue. In this way, the
brackets 1060(1) and 1060(2) secure the reservoir 1002(B) in
position. In alternative embodiments, the anchor loops 1061(1),
1061(2), 1062(1), and 1062(2) may be replaced with pads or other
members that enable the reservoir 1002(B) to be secured to the
recipient using, for example, a bonding agent (e.g., bone cement or
other biocompatible adhesive), sutures, etc.
[0087] For ease of illustration, FIGS. 10A and 10B illustrate
anchor loops and brackets, respectively, with reference to
implantable reservoirs. It is to be appreciated that these fixation
mechanisms may be used with other implantable components of a
delivery system to facilitate attachment of those components to a
recipient's tissue.
[0088] FIG. 10C illustrates a fixation mechanism for the distal end
of a delivery tube 1006 of a delivery system. In this embodiment,
the delivery tube 1006 includes surface features 1064 that are
configured to facilitate attachment of a bonding agent (e.g., bone
cement or other biocompatible adhesive) to the surface of the
delivery tube or to allow natural retention of the tube by body
tissue, fibrotic response, etc. The bonding agent then secures the
distal end of the delivery tube 1006 to the recipient's tissue.
[0089] The surface features 1064 (i.e., the fixation mechanism) may
have a number of different configurations. In one embodiment, the
surface features comprise a plurality of recesses in the form of
spaced grooves or troughs and/or ridges. The grooves/ridges may
have different shapes and configurations. For example,
grooves/ridges may have cross-sectional shapes that are
rectangular, triangular, trapezoidal, etc. It is also to be
appreciated that grooves in alternative embodiments may have
geometries that include different undercut regions. For example,
alternative grooves may be T-shaped, J-shaped, dovetailed,
frustoconical, etc. The undercut regions may function to create a
mechanical lock, or an interlock between a bonding agent and the
surface of the delivery tube 1006.
[0090] In another embodiment, the surface features 1064 comprise a
collection of depressions and/or protrusions. The protrusions may
have a number of different shapes (e.g., parabolic, square,
rectangular, arcuate, etc.).
[0091] In a still other embodiment, the surface features 1064
comprise include a plurality of recesses in the form of pores. The
pores may have irregular shapes that potentially result in
mechanical locking. That is, the irregular shape of the pores may
cause the bonding agent and/or tissue to undergo one or more turns
when the bonding agent fills the pore
[0092] For ease of illustration, FIG. 10C illustrates surface
features in/on the surface of a delivery tube. It is to be
appreciated that these and other surface features may be used in/on
the surfaces of other implantable components of a delivery system
to facilitate attachment of a bonding agent thereto for subsequent
securement to tissue.
[0093] FIG. 11 illustrates a delivery tube positioning mechanism
1170 that may be used in accordance with embodiments presented
herein to locate the distal end of a delivery tube (not shown in
FIG. 11) adjacent to a target location (e.g., the round window
121). Delivery tube positioning mechanism 1170 comprises two
sub-components, namely extension arm 1171 and extension arm
1175.
[0094] Sub-component 1171 includes arm 1172 which is an integral
part of housing 1146 (where the cross-hatching of housing 1146 seen
in FIG. 11 corresponds to the wall of the housing). Arm 1172 may be
part of the same casting forming at least part of housing 1146
(i.e., the arm 1172 and at least a portion of the housing 1146 form
a monolithic component), although in an alternate exemplary
embodiment, arm 1172 may be a separate component that is attached
to the housing 1146 (e.g., via laser welding). In an exemplary
embodiment, the casting may be made partially or totally out of
titanium. In this regard, it is noted that the delivery tube
positioning mechanism 1170 may be partially or totally formed from
titanium, and the housing 1146 may be formed from a different
material. Sub-component 1171 also includes flange 1173 which forms
a female portion of ball joint 1174.
[0095] The delivery tube positioning mechanism 1170 further
includes subcomponent 1175. Sub-component 1175 comprises the male
portion of the ball joint 1174, in the form of a ball 1176, arm
1177, trolley 1178 and delivery tube support 1179. Delivery tube
support 1179 is depicted as being in the form of a collar, and
receives and otherwise holds a delivery tube therein. For ease of
illustration, the delivery tube has been omitted from FIG. 11.
[0096] Ball joint 1174 permits the ball 1176 of sub-component 1175
to move within the female portion, thereby permitting sub-component
1175 to articulate relative to sub-component 1171. This
articulation permits the delivery tube to likewise articulate. Ball
joint 1174 also enables the delivery tube to be positioned at an
adjustably fixed location relative to the target location. In an
exemplary embodiment, the ball joint 1174 permits the location of
the delivery tube to be adjustable in two degrees of freedom,
represented by arrows 1 and 2 (first and second degrees of freedom,
respectively), in FIG. 11. In some embodiments, the joint may
permit the location of the delivery tube to be adjustable in only
one degree of freedom or in more than two degrees of freedom.
[0097] While delivery tube positioning mechanism 1170 is depicted
with a ball joint 1174, other types of joints may be utilized. By
way of example, the joint may comprise a malleable portion of a
structural component of the delivery tube positioning mechanism
1170 that permits the delivery tube to be positioned as just
detailed or variations thereof. In an exemplary embodiment, the
joint is an elastically deformable portion or plastically
deformable portion or is a combination of elastically deformable
and plastically deformable portions so as to enable the adjustment
of the location of the delivery tube in the at least one degree of
freedom.
[0098] The collar 1179 has an exterior surface 1179(1) and an
interior surface 1179(2), configured to receive the delivery tube.
The interior diameter of the collar, formed by interior surface
1179(2) is approximately the same as the outer diameter of the
cylindrical body of the delivery tube.
[0099] As noted, delivery tube support 1179 secures the delivery
tube to the delivery tube positioning mechanism 1170. This
removable securement may be, in some embodiments, sufficient to
prevent the delivery tube from substantially moving from the
retained location in the delivery tube support 1179. In an
exemplary embodiment, interlock between the delivery tube support
1179 and the delivery tube is provided by an interference fit
between inner surface 1179(1) and the delivery tube. In an
alternate embodiment, interlock between the delivery tube support
1179 and the delivery tube is implemented as corresponding mating
threads on inner surface 1179(1) and the delivery tube.
[0100] In another embodiment, O-rings or the like may be used to
secure the delivery tube within the delivery tube support 1179.
Grooves on the delivery tube and/or on the collar may be included
to receive the O-ring. Alternatively, compression of the O-ring
between the delivery tube and the collar provides sufficient
friction to retain the delivery tube in the delivery tube support
1179.
[0101] In a further embodiment, delivery tube support 1179 or the
delivery tube includes a biased extension that is adjusted against
the bias to insert the delivery tube into the support. The
extension may engage a detent on the opposing surface to interlock
the delivery tube and the support. Other embodiments include
protrusions and corresponding channels on opposing surfaces of the
delivery tube and the delivery tube support 1179. An exemplary
embodiment includes a spring-loaded detent that interfaces with a
detent receiver of the opposing surface to hold the delivery tube
in the delivery tube support 1179. Adhesive may be used to
interlock the delivery tube in the delivery tube support 1179.
[0102] The trolley 1178, which is rigidly connected to delivery
tube support 1179, is configured to move linearly in the direction
of arrow 3 parallel to the longitudinal direction of extension of
arm 1177. In this exemplary embodiment, arm 1177 includes tracks
with which trolley 1178 interfaces to retain trolley 1178 to arm
1177. These tracks also establish trolley 1178 and arm 1177 as a
telescopic component configured to enable the adjustment of the
location of delivery tube support 1179, and thus the delivery tube
when received therein, in at least one degree of freedom (i.e., the
degree of freedom represented by arrow 3). It is noted that other
embodiments may permit adjustment in at least two or at least three
degrees of freedom. Thus, when the trolley component is combined
with the aforementioned joint 1174, the delivery tube positioning
mechanism 1170 enables the location of the delivery tube to be
adjustable in at least two or at least three degrees of
freedom.
[0103] Movement of the trolley 1178 along arm 1177 may be
accomplished via a jack screw mechanism where the jack screw is
turned via a screw driver or a hex-head wrench. Movement of the
trolley 1178 may also or alternatively be achieved via application
of a force thereto that overcomes friction between the trolley 1178
and the arm 1177. Any device, system or method that permits trolley
1178 to move relative to arm 1172 may be used in some embodiments
detailed herein and variations thereof.
[0104] It may be seen that arm 1172 of delivery tube positioning
mechanism 1170 includes screw hole 1180. Screw hole 1180 is
configured to receive a bone screw (not shown in FIG. 11) for
securing of the delivery tube positioning mechanism 1170 to the
recipient's tissue. While screw hole 1180 is depicted as being
located on (in) arm 1172, in other embodiments, screw holes may be
located elsewhere on the delivery tube positioning mechanism
1170.
[0105] In certain embodiments, the fixation mechanisms used to
retain a distal end of a delivery tube in place at a target
location are the physical properties of the delivery tube. For
example, FIGS. 12A and 12B are cross-sectional views illustrating a
delivery tube 1206 that is conformable, but also has sufficient
rigidity to provide stability and to remain in a selected position
and configuration. FIG. 12A illustrates a lateral cross-sectional
view of the delivery tube 1206, while FIG. 12B illustrates an
elongate cross-sectional view of the delivery tube 1206.
[0106] The delivery tube 1206 comprises a carrier 1282 that forms a
lumen 1283. A treatment substance is delivered from a reservoir to
a target location through the lumen 1283. The carrier 1282 may be
formed from, for example, a biocompatible elastomer (e.g., silicone
rubber) or similar substantially comfortable/pliable material. The
carrier 1282 has material properties so as to prevent egress of a
treatment substance from the lumen 1283 as well as to prevent the
ingress of bodily fluids.
[0107] The delivery tube 1206 also comprises a stiffening element
1284 extending along all or part of the elongate length of the
delivery tube. In the embodiments of FIGS. 12A and 12B, the
stiffening element 1284 is an elongate wire (e.g., platinum,
titanium, etc.) embedded in the carrier 1382. In other embodiments,
the stiffening element 1284 may be formed from a polymer material.
In general, the carrier 1282 and stiffening element 1284 are
conformable to a selected configuration (e.g., location, position,
orientation, etc.). The stiffening element 1284 has mechanical
properties (e.g., rigidity, malleability, etc.) such that the
delivery tube 1206 remains in the selected configuration.
[0108] FIGS. 13A and 13B illustrate another delivery tube 1306 that
is conformable, but also has sufficient rigidity to provide
stability and to remain in a selected position. The delivery tube
1306 comprises a carrier 1382 surrounded by a stiffening sheath
1384. FIG. 13A illustrates a lateral cross-sectional view of the
delivery tube 1306, while FIG. 13B is a side view from which part
of the stiffening sheath 1384 has been omitted.
[0109] The carrier 1382 forms a lumen 1383 that carries a treatment
substance from a reservoir to a target location. The carrier 1282
may be formed from, for example, a biocompatible elastomer or
similar substantially conformable/pliable material. The carrier
1382 has material properties so as to prevent egress of a treatment
substance from the lumen 1383 as well as to prevent the ingress of
bodily fluids.
[0110] The stiffening sheath 1384 substantially surrounds the
carrier 1382 and extends along all or part of the elongate length
of the delivery tube. In the embodiments of FIGS. 13A and 13B, the
stiffening sheath is a mesh (e.g., titanium, wire, polymer, etc.).
In general, the carrier 1382 and stiffening sheath 1384 are
conformable to a selected configuration. The stiffening sheath 1384
has mechanical properties (e.g., rigidity, malleability, etc.) such
that the delivery tube 1306 remains in the selected
configuration.
[0111] It is to be appreciated the embodiments of FIGS. 12A-13B are
illustrative and other stiffening elements or mechanisms may be
used to form a delivery tube with physical properties that assist
in retention of the distal end of the delivery tube at a target
location. For example, the carrier of the delivery tube may be
formed from a flexible material that protects against external
force (e.g., using shape memory materials).
[0112] One potential issue with certain delivery systems is the
accretion (build-up) of undelivered treatment substance particles
within the system. For example, if the delivery of a treatment
substance is started and is then stopped for a period of time
(e.g., in cases of pain relief or to combat infections), portions
of the treatment substance may remain in the system outside of the
reservoir. These undelivered portions of the treatment substance
outside of the reservoir may precipitate (e.g., crystalize) and
potentially clog the system at the delivery tube, the delivery
device, etc. so as to inhibit subsequent delivery of the treatment
substance. As noted above, certain embodiments presented herein are
directed to accretion prevention (anti-accretion) mechanisms that
prevent the buildup of precipitated particles within a delivery
system that can inhibit subsequent treatment substance delivery.
FIG. 14 illustrates an example delivery system 1400 that includes a
flushing module 1475 that operates as an anti-accretion
mechanism.
[0113] The delivery system 1400 is similar to the arrangement of
FIG. 5 where a magnetic attraction is used to propel a treatment
substance from an implantable reservoir. More specifically, the
delivery system 1400 comprises a magnetic element 1434 implanted
abutting a first section of the outer surface 229 of the
recipient's skull. The magnetic element 1434 may be formed from a
ferromagnetic or ferrimagnetic material and may be magnetized
(i.e., a permanent magnet) or non-magnetized. FIG. 14 illustrates
an embodiment in which the magnetic element 1434 is a permanent
magnet. The magnetic element 1434 may be secured to the superior
portion 118 of recipient's temporal bone 115 using, for example, a
bone screw (not shown) or another fixation mechanism (e.g.,
adhesive).
[0114] As shown, a treatment substance reservoir 1402 is implanted
so as to abut an externally-facing surface 1425 of the magnetic
element 1434 (i.e., a surface facing away from the recipient's
temporal bone 115). The treatment substance reservoir 1402 may be
secured to the magnetic element 1434 and/or the recipient's
temporal bone using one or more fixation mechanisms described
elsewhere herein. The treatment substance reservoir 1402 is at
least partially filled with a treatment substance.
[0115] The flushing module 1475 comprises a second magnetic element
1444 implanted abutting a second section of the outer surface 229
of the recipient's skull. The magnetic element 1444 may be formed
from a ferromagnetic or ferrimagnetic material and may be
magnetized or non-magnetized. FIG. 14 illustrates an embodiment in
which the magnetic element 1444 is a permanent magnet. The magnetic
element 1444 may be secured to the superior portion 118 of
recipient's temporal bone 115 using, for example, a bone screw (not
shown) or another fixation mechanism.
[0116] As shown, a flushing reservoir 1452 is implanted so as to
abut an externally-facing surface 1455 of the magnetic element 1444
(i.e., a surface facing away from the recipient's temporal bone
115). The treatment substance reservoir 1402 may be secured to the
magnetic element 1434 and/or the recipient's temporal bone using
one or more fixation mechanisms described elsewhere herein. As
described further below, the flushing reservoir 1452 is at least
partially filled with a flushing solution (e.g., saline).
[0117] The treatment substance reservoir 1402 is fluidically
coupled to the proximal end of a connector tube 1456 via a one-way
valve 1458. Similarly, the flushing reservoir 1452 is fluidically
coupled to a proximal end of connector tube 1466 via a one-way
valve 1468. The connector tubes 1456 and 1466 terminate at a
three-port valve 1470. That is, the valve 1470 has a first port
connected to the connector tube 1456, a second port connected to
the connector tube 1466, and third port connected to a delivery
tube 1406.
[0118] In general, the valves 1458 and 1468 allow a treatment
substance or flushing solution, respectively, to pass from the
respective reservoirs to the valve 1470. The valve 1470 is
configured to allow either the treatment substance or the flushing
solution to pass to the delivery tube 1406. The valve 1470 is
configured to prevent the treatment substance from passing into the
connector tube 1466 and to prevent the flushing solution from
passing into the connector tube 1456.
[0119] It is to be appreciated that the use of a three-port valve
1470 is merely illustrative and that other valves may be used in
alternative embodiments. For example, in certain embodiments, the
three-port valve 1470 may be replaced with separate one-way valves
positioned at the distal end of each of the connector tunes 1456
and 1466.
[0120] In the embodiment of FIG. 14, an external magnet 1436 may be
placed adjacent to the recipient's tissue 219 that covers the
treatment substance reservoir 1402. The poles of the external
magnet 536 and the magnetic element 1434 may be oriented so that
the external magnet and the magnetic element will be magnetically
attracted to one another when in proximity to one another. The
mutual attraction between the external magnet 1436 and the magnetic
element 1434 compresses the recipient's tissue 219 adjacent to the
treatment substance reservoir 1402. The compression of the tissue,
in turn, compresses the reservoir 1402. The positioning of the
reservoir 1402 abutting the magnetic element 1434 and the superior
portion 118 of the mastoid 115 provides a rigid surface that
counters the compression of the tissue 219. As a result, a pressure
change occurs in the treatment substance reservoir 1402 so as to
force a portion of the treatment substance out of the reservoir
through valve 1458. Once the magnet 1436 is removed, the flow of
treatment substance from the reservoir 1402 terminates.
[0121] The valve 1458 may be a check valve or a stop-check valve
(e.g., a magnetically operated valve). In embodiments in which the
valve 1458 is a magnetically operated valve, the external magnet
1436 may be configured so as to compress the treatment substance
reservoir 1402 and additionally open valve 1458.
[0122] Additionally, the external magnet 1436 may be placed
adjacent to the recipient's tissue 219 that covers the flushing
reservoir 1452 so as to activate the flushing module 1475. More
specifically, the poles of the external magnet 1436 and the
magnetic element 1444 may be oriented so that the external magnet
and the magnetic element will be magnetically attracted to one
another when in proximity to one another. The mutual attraction
between the external magnet 1436 and the magnetic element 1444
compresses the recipient's tissue 219 adjacent to the flushing
reservoir 1452. The compression of the tissue, in turn, compresses
the reservoir 1452. The positioning of the reservoir 1452 abutting
the magnetic element 1444 and the superior portion 118 of the
mastoid 115 provides a rigid surface that counters the compression
of the tissue 219. As a result, a pressure change occurs in the
flushing reservoir 1452 so as to force a portion of the flushing
solution out of the reservoir through valve 1468. Once the magnet
1436 is removed, the flow of the flushing solution from the
reservoir 1452 terminates.
[0123] The valve 1468 may be a check valve or a stop-check valve
(e.g., a magnetically operated valve). In embodiments in which the
valve 1468 is a magnetically operated valve, the external magnet
1436 may be configured so as to compress the reservoir 1452 and
additionally open valve 1452.
[0124] The activation of the flushing module 1475 to release the
flushing solution may occur after delivery of a treatment
substance. The flushing solution is designed to clean the
downstream portions of the delivery system, including the delivery
tube 1406 and the delivery device 1408. That is, the flushing
solution substantially removes any remaining treatment substance
from the system so that the treatment substance does not
precipitate and accrete within the system.
[0125] In the embodiment of FIG. 14, the same external magnet 1436
is used to activate both the treatment substance delivery and the
flushing mechanisms. In certain arrangements, the flushing
reservoir 1452 is implanted a certain distance away from the
reservoir 1402 such that activation of the treatment substance
delivery mechanism does not affect the flushing module 1475, and
vice versa. However, in another arrangement shown in FIG. 14, the
treatment substance delivery and the flushing mechanisms are
responsive to different poles of the magnet 1436.
[0126] A magnet, such as magnet 1436, is an object that produces a
magnetic field that interacts with other magnetic fields. Magnets
have two poles, typically referred to as the "north pole" and the
"south pole." The magnetic field may be represented by field lines
that start at a magnet's north pole and end at the magnet's south
pole. The magnetic force (attraction) between to magnetic objects
is caused by the magnet's magnetic field and points in the
direction of the field lines. For example, if two magnets are next
to each other and their north poles are facing towards one another
(or conversely if their south poles are facing towards one
another), the field lines move away from each other and thus the
magnets repel one another. In contrast, if two magnets are next to
each other and a north pole of one magnet faces the south pole of
the other magnet, the magnets will be attracted to one another.
[0127] The embodiment of FIG. 14 makes use of the opposing poles of
the magnets to ensure that only one of the treatment substance
delivery or the flushing mechanism is activated at any one time.
More specifically, the magnetic element 1434 may be implanted such
that either the north or the south pole of the magnetic element
1434 faces the tissue of the 219 of the recipient. The magnetic
element 1444 is implanted such that the opposing pole faces the
tissue 219 of the recipient (i.e., if the magnetic element 1434 has
a north pole facing the tissue, the magnetic element 144 has a
south pole facing the tissue). Similarly, in embodiments using
magnetic valves, the valves 1458 and 1468 may be similarly
responsive to different magnet poles.
[0128] The opposing surfaces 1437(1) and 1437(2) of the external
magnet may be selected positioned adjacent the recipient's tissue
219 to activate either the treatment substance delivery or the
flushing mechanisms. The opposing surfaces 1437(1) and 1437(2) may
also be labeled so that user can easily identify how the external
magnet 1436 should be placed to activate each mechanism.
[0129] In an alternative embodiment of FIG. 14, the flushing
reservoir 1452 could also or alternatively be coupled to the
treatment substance reservoir 1402 so as to flush both the
treatment substance reservoir 1402 and the delivery tube 1406.
Alternatively, a double valve or other mechanism may be present to
enable selective and independent flushing of the treatment
substance reservoir 1402 and the delivery tube 1406.
[0130] Accretion prevention (anti-accretion) mechanisms in
accordance with embodiments presented herein may further include
different shapes/configurations for the delivery device 1408 that
prevent accretion. For example, the delivery device 1408 may
include grooves, a sharp bevel, and/or a sponge/del device that is
held below a groove in the tube to absorb any treatment substance
that might be residually in the delivery tube 1406.
[0131] FIG. 15 is a cross-sectional view of part of another
delivery system 1500 configured to prevent accretion resulting from
treatment substance precipitation. In this embodiment, the delivery
system 1500 is similar to the arrangements of FIGS. 8A-8C or FIG.
9, but further includes a replaceable delivery tube 1506 that
passes through the recipient's tympanic membrane 104.
[0132] More specifically, a replaceable delivery tube 1506 has a
proximal end that is fluidically coupled to a valve or reservoir
and a distal end 1514 that is fluidically coupled to the round
window 121. A delivery device 1508 is positioned in the distal end
1514 adjacent to the round window 121. Additionally, an elongate
fixed sheath 1590 is extends from the valve or reservoir and to
distal end 1594 that is attached to the round window 121 and/or
another area of the recipient.
[0133] The delivery tube 1506 and the outer fixed sheath 1590
extend through the recipient's tympanic membrane 104 to the round
window 121. In particular, the delivery tube 1506 and the outer
fixed sheath 1590 pass through a surgically formed opening within
the tympanic membrane 104. A surgically placed grommet 1556 is
disposed around the fixed sheath 1590 so as to seal the opening in
the tympanic membrane 104 around the fixed sheath 1590.
[0134] As shown, the fixed sheath 1590, and not the delivery tube
1506, is affixed to the tympanic membrane 104 (via the grommet
1556) and the recipient's inner ear 107. Additionally, the delivery
tube 1506 is slideably engaged with the fixed sheath 1590. As a
result, the delivery tube 1506 may be removed from the recipient's
ear canal without damaging the tympanic membrane 104 or the inner
ear 107. A replacement delivery tube 1506 may then be inserted.
Periodic replacement of the delivery tube 1506 (and the delivery
device 1508 therein) prevents accretion of precipitated treatment
substance particles.
[0135] Embodiments have been primarily described above with
reference to the coupling of the distal end of the delivery tube to
a recipient's inner ear (e.g., round window) for delivery of the
treatment substances to the cochlea. It is to be appreciated that
treatment substances may be delivered to other regions of the
recipient's ear. For example, the distal end of the delivery tube
can be attached to or formed as a pouch or a sheet to envelope or
cover a component of another device (e.g., a cochlear implant,
direct acoustic stimulator, etc.) that has been infected or
implanted in high risk location.
[0136] It is also to be appreciated that other locations and/or
configurations for the various components disclosed herein are
possible. For example, in one alternative arrangement a reservoir,
valve, etc. may be positioned inside the recipient's cochlea.
[0137] Additionally, embodiments have been primarily described with
reference to the use of a single reservoir for a treatment
substance. It is to be appreciated that other embodiments may use
two different reservoirs for different treatment substances.
Alternatively, one reservoir may be subdivided in two sections for
independent delivery of two different treatment substances. In one
such embodiment, the two reservoirs or sub-reservoirs may be
activated independently or a single push could activate both of the
reservoirs or sub-reservoirs simultaneously.
[0138] It is to be appreciated that embodiments presented herein
are not mutually exclusive and can be combined in various manners
and arrangements.
[0139] The invention described and claimed herein is not to be
limited in scope by the specific preferred embodiments herein
disclosed, since these embodiments are intended as illustrations,
and not limitations, of several aspects of the invention. Any
equivalent embodiments are intended to be within the scope of this
invention. Indeed, various modifications of the invention in
addition to those shown and described herein will become apparent
to those skilled in the art from the foregoing description. Such
modifications are also intended to fall within the scope of the
appended claims.
* * * * *