Patent Publication Number: US-2020297924-A1

Title: Bioactive agent distribution

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to U.S. Provisional Application No. 62/562,076, entitled T BIOACTIVE AGENT DISTRIBUTION, filed on Sep. 22, 2017, naming Daniel SMYTH of Mechelen, Belgium as an inventor, the entire contents of that application being incorporated herein by reference in its entirety. 
    
    
     BACKGROUND 
     Hearing loss, which may be due to many different causes, is generally of two types: conductive and sensorineural. Sensorineural hearing loss is due to the absence or destruction of the hair cells in the cochlea that transduce sound signals into nerve impulses. Various hearing prostheses are commercially available to provide individuals suffering from sensorineural hearing loss with the ability to perceive sound. One example of a hearing prosthesis is a cochlear implant. 
     Conductive hearing loss occurs when the normal mechanical pathways that provide sound to hair cells in the cochlea are impeded, for example, by damage to the ossicular chain or the ear canal. Individuals suffering from conductive hearing loss may retain some form of residual hearing because the hair cells in the cochlea may remain undamaged. 
     Individuals suffering from hearing loss typically receive an acoustic hearing aid. Conventional hearing aids rely on principles of air conduction to transmit acoustic signals to the cochlea. In particular, a hearing aid typically uses an arrangement positioned in the recipient&#39;s ear canal or on the outer ear to amplify a sound received by the outer ear of the recipient. This amplified sound reaches the cochlea causing motion of the perilymph and stimulation of the auditory nerve. Cases of conductive hearing loss typically are treated by means of bone conduction hearing aids. In contrast to conventional hearing aids, these devices use a mechanical actuator that is coupled to the skull bone to apply the amplified sound. 
     In contrast to hearing aids, which rely primarily on the principles of air conduction, certain types of hearing prostheses commonly referred to as cochlear implants convert a received sound into electrical stimulation. The electrical stimulation is applied to the cochlea, which results in the perception of the received sound. 
     It is also noted that the electrode array of the cochlear implant generally shows utilitarian results if it is inserted in a cochlea. 
     SUMMARY 
     In accordance with an exemplary embodiment, there is a device comprising a drug delivery device configured to simultaneously interface with a scala tympani and a scala vestibuli of a cochlea. 
     In accordance with another exemplary embodiment, there is a device, comprising a prosthesis configured to circulate perilymph within a cochlea. 
     In accordance with another exemplary embodiment, there is a device, comprising a means for interfacing with a cochlea and a means for distributing a therapeutic substance within a cochlea. 
     In accordance with another exemplary embodiment, there is a method, comprising driving an effective amount of a therapeutic substance to an apical region of the cochlea. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments are described below with reference to the attached drawings, in which: 
         FIG. 1  is a perspective view of an exemplary hearing prosthesis; 
         FIGS. 2A-2H  are views of exemplary electrode arrays to which the teachings detailed herein can be applicable; 
         FIGS. 3A and 3B  are side and perspective views of an electrode assembly extended out of an embodiment of an insertion sheath of the insertion tool illustrated in  FIG. 2 ; 
         FIGS. 4A-4E  are simplified side views depicting an exemplary insertion process of the electrode assembly into the cochlea; 
         FIGS. 5-7  present an exemplary embodiment of an exemplary therapeutic substance delivery system; 
         FIG. 8  presents another exemplary embodiment of an exemplary therapeutic substance delivery system; 
         FIGS. 9-12  functionally depict a principle of operation according to an exemplary embodiment; 
         FIG. 13-19  functionally conceptually depict exemplary usage of an exemplary embodiment; 
         FIGS. 20-21  depict another exemplary embodiment; 
         FIGS. 22-26  variously depict other exemplary embodiments; 
         FIGS. 27 and 28  variously depict other exemplary embodiments in use; 
         FIGS. 29-31  variously depict other exemplary embodiments; 
         FIGS. 32-36  variously depict other exemplary embodiments; 
         FIGS. 37-41B  depict other exemplary embodiments; 
         FIG. 42  depicts an exemplary pump that can utilitarian value with respect to some embodiments; and 
         FIGS. 43-45  variously depict other exemplary embodiments. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  is a perspective view of an exemplary cochlear implant  100  implanted in a recipient having 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 . Acoustic pressure or sound waves  103  are 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  that vibrates in response to sound waves  103 . This vibration is coupled to oval window or fenestra ovalis  112  through the three bones of the middle ear  105 , collectively referred to as the ossicles  106 , and comprising the malleus  108 , the incus  109 , and the stapes  111 . Ossicles  106  filter and amplify the vibrations delivered by tympanic membrane  104 , causing oval window  112  to articulate, or vibrate. This vibration sets up waves of fluid motion of the perilymph within cochlea  140 . Such fluid motion, in turn, activates hair cells (not shown) inside the cochlea which in turn causes nerve impulses to be generated which are transferred through spiral ganglion cells (not shown) and auditory nerve  114  to the brain (also not shown) where they are perceived as sound. 
     The exemplary cochlear implant illustrated in  FIG. 1  is a partially-implanted stimulating medical device. Specifically, cochlear implant  100  comprises external components  142  attached to the body of the recipient, and internal or implantable components  144  implanted in the recipient. External components  142  typically comprise one or more sound input elements for detecting sound, such as microphone  124 , a sound processor (not shown), and a power source (not shown). Collectively, these components are housed in a behind-the-ear (BTE) device  126  in the example depicted in  FIG. 1 . External components  142  also include a transmitter unit  128  comprising an external coil  130  of a transcutaneous energy transfer (TET) system. Sound processor  126  processes the output of microphone  124  and generates encoded stimulation data signals which are provided to external coil  130 . 
     Internal components  144  comprise an internal receiver unit  132  including a coil  136  of the TET system, a stimulator unit  120 , and an elongate stimulating lead assembly  118 . Internal receiver unit  132  and stimulator unit  120  are hermetically sealed within a biocompatible housing commonly referred to as a stimulator/receiver unit. Internal coil  136  of receiver unit  132  receives power and stimulation data from external coil  130 . Stimulating lead assembly  118  has a proximal end connected to stimulator unit  120 , and extends through mastoid bone  119 . Lead assembly  118  has a distal region, referred to as electrode assembly  145 , a portion of which is implanted in cochlea  140 . 
     Electrode assembly  145  can be inserted into cochlea  140  via a cochleostomy  122 , or through round window  121 , oval window  112 , promontory  123 , or an opening in an apical turn  147  of cochlea  140 . Integrated in electrode assembly  145  is an array  146  of longitudinally-aligned and distally extending electrode contacts  148  for stimulating the cochlea by delivering electrical, optical, or some other form of energy. Stimulator unit  120  generates stimulation signals each of which is delivered by a specific electrode contact  148  to cochlea  140 , thereby stimulating auditory nerve  114 . 
       FIG. 2A  depicts a conceptual side view of a portion of electrode array  146 , depicting four electrode contacts  148  evenly spaced along a longitudinal axis of the electrode array  146 . It is noted that in some alternate embodiments, the electrode is not evenly spaced.  FIG. 2B  depicts a conceptual cross-sectional view through one of the electrode contacts  148 , which also depicts the carrier  149  of the electrode contact  148 . In an exemplary embodiment, the carrier  149  is made of silicone. Not depicted in the figures are electrical leads and stiffener components that are sometimes embedded in the carrier  149 . The embodiment of  FIG. 2B  represents an electrode array  146  that has a generally rectangular cross-section.  FIG. 2C  depicts an alternate embodiment where the electrode array  146  has a generally circular cross-section. It is also noted that in some exemplary embodiments, the cross-section is oval shaped. Thus, the embodiment of  FIGS. 2A-2C  is a species of the genus of an electrode array having a generally continuously curving cross-section. Any electrode array of any cross-section or any configuration can be utilized with the teachings detailed herein. 
     The electrode contacts  148  depicted in  FIGS. 2A-2C  are so-called flat contacts. In this regard, the surface of the electrode contact that faces the wall of the cochlea/the faces away from the longitudinal axis of the electrode array  146  is flat. Conversely, as seen in  FIGS. 2D-2H , in some alternate embodiments, the electrode contacts  148  are so-called half band electrodes. In some exemplary embodiments, a band of contact material is “smashed” or otherwise compressed into a “half band,” as seen in the figures. It is noted that by “half band,” this does not mean that the electrode contact must necessarily span half of the outside diameter of the electrode array, as is the case in  FIGS. 2G and 2H . The term is directed towards the configuration of the electrode itself as that term has meaning in the art. Any electrode contact that can have utilitarian value according to the teachings detailed herein can be utilized in at least some exemplary embodiments. 
     As can be seen from  FIGS. 2A-2H , the positioning of the electrode contacts relative to the carrier  149  can vary with respect to alignment of the outer surface of the carrier with the outer surface of the contact. For example,  FIGS. 2A, 2E, and 2F  depict the outer surface of the contacts  148  as being flush with the outer surface of the carrier  149 . Conversely,  FIGS. 2C and 2G  depict the contact  148  as being recessed with respect to the outer surface of the carrier  149 , while  FIG. 2H  depicts the contact  148  as being proud relative to the outer surface of the contact  149 . It is noted that these various features are not limited to the specific contact geometry and/or the specific carrier geometry depicted in the figures, and that one or more features of one exemplary embodiment can be combined with one or more features of another exemplary embodiment. For example, while  FIG. 2H  depicts a half band contact as being proud of the carrier  149  having a generally circular cross-section, a flat electrode such as that depicted in  FIG. 2A  can be proud of the carrier as well. 
       FIGS. 3A and 3B  are side and perspective views, respectively, of representative electrode assembly  145 . As noted, electrode assembly  145  comprises an electrode array  146  of electrode contacts  148 . Electrode assembly  145  is configured to place electrode contacts  148  in close proximity to the ganglion cells in the modiolus. Such an electrode assembly, commonly referred to as a perimodiolar electrode assembly, is manufactured in a curved configuration as depicted in  FIGS. 3A and 3B . When free of the restraint of a stylet or insertion guide tube, electrode assembly  145  takes on a curved configuration due to it being manufactured with a bias to curve, so that it is able to conform to the curved interior of cochlea  140 . As shown in  FIG. 3B , when not in cochlea  140 , electrode assembly  145  generally resides in a plane  350  as it returns to its curved configuration. That said, it is noted that the teachings detailed herein and/or variations thereof can be applicable to a so-called straight electrode array, which electrode array does not curl after being free of a stylet or insertion guide tube etc., but instead remains straight. It is noted that when in the cochlea, the electrode assembly  145  takes on a conical shape with respect to plane  350  in that it can be described as winding upward away from the plane  350  about an axis normal thereto, owing to the shape of the cochlea (more on this below). 
     The perimodiolar electrode assembly  145  of  FIGS. 3A and 3B  is pre-curved in a direction that results in electrode contacts  148  being located on the interior of the curved assembly, as this causes the electrode contacts to face the modiolus when the electrode assembly is implanted in or adjacent to cochlea  140 . 
     It is also noted that while the embodiments of  FIGS. 2A-3B  have been presented in terms of a so-called non-tapered electrode array (where the cross-sections of the array on a plane normal to the longitudinal axis at various locations along the longitudinal axis (e.g., in between each electrode (or a majority of the electrodes), in the middle of each electrode (or a majority of the electrodes) etc.) have generally the same cross-sectional area and shape), in an alternate embodiment, the teachings detailed herein can be applicable to a so-called tapered electrode, where the cross-sectional areas on planes taken normal to the longitudinal axis decrease with location towards the distal end of the electrode array. 
       FIGS. 4A-4E  depict an exemplary insertion regime of an electrode assembly according to an exemplary embodiment. As shown in  FIG. 4A , the combined arrangement of an insertion guide tube  300  and electrode assembly  145  is substantially straight. This is due in part to the rigidity of insertion guide tube  300  relative to the bias force applied to the interior wall of the guide tube by pre-curved electrode assembly  145 . 
     As noted, in some embodiments, the electrode assembly  145  is biased to curl and will do so in the absence of forces applied thereto to maintain the straightness. That is, electrode assembly  145  has a memory that causes it to adopt a curved configuration in the absence of external forces. As a result, when electrode assembly  145  is retained in a straight orientation in guide tube  300 , the guide tube prevents the electrode assembly from returning to its pre-curved configuration. In the embodiment configured to be implanted in scala tympani of the cochlea, electrode assembly  145  is pre-curved to have a radius of curvature that approximates and/or is less than the curvature of medial side of the scala tympani of the cochlea. Such embodiments of the electrode assembly are referred to as a perimodiolar electrode assembly, and this position within cochlea  140  is commonly referred to as the perimodiolar position. In some embodiments, placing electrode contacts in the perimodiolar position provides utility with respect to the specificity of electrical stimulation, and can reduce the requisite current levels thereby reducing power consumption. 
     As shown in  FIGS. 4B-4D , electrode assembly  145  may be continually advanced through insertion guide tube  300  while the insertion sheath is maintained in a substantially stationary position. This causes the distal end of electrode assembly  145  to extend from the distal end of insertion guide tube  300 . As it does so, the illustrative embodiment of electrode assembly  145  bends or curves to attain a perimodiolar position, as shown in  FIGS. 4B-4D , owing to its bias (memory) to curve. Once electrode assembly  145  is located at the desired depth in the scala tympani, insertion guide tube  300  is removed from cochlea  140  while electrode assembly  145  is maintained in a stationary position. This is illustrated in  FIG. 4E . 
       FIG. 5  depicts an exemplary drug delivery device, the details of which will be provided below. It can be utilitarian to have a prompt and/or 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. Embodiments of the teachings herein can facilitate extended delivery of treatment substances, as well as facilitating prompt delivery of such substances. 
       FIG. 5  illustrates an implantable delivery system  200  that can be utilized with the teachings detailed herein, and otherwise modified as detailed by way of example below. The delivery system has a passive actuation mechanism. However, it is noted that the delivery system  200  can also or instead have an active actuation system. 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&#39;s inner ear (e.g., the target location is the interior of the recipient&#39;s cochlea  140 ).  FIG. 6  illustrates a first portion of the delivery system  200 , while  FIG. 7  is a cross-sectional view of a second portion of the delivery system  200 . 
     Delivery system  200  of  FIGS. 5-7  comprises a reservoir  202 , a valve  204 , a delivery tube  206 , and a delivery device  208  ( FIG. 7 ). 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 , and any of the other delivery systems detailed herein and/or variations thereof, could be used with, for example, cochlear implants, such as that presented in  FIG. 1 , direct acoustic stimulators, middle ear implants, bone conduction devices, etc. The implantable components (e.g., reservoir, valve, delivery tube, etc.) of delivery system  200  (or any other delivery system detailed herein) could be separate from or integrated with the other components of the implantable auditory prosthesis. Additionally, the delivery system  200  can include, or operate with, an external magnet  210 , which is separate from or part of the implantable auditory prostheses, for purposes of, e.g., controlling operation of valve  204 . 
     The reservoir  202  is positioned within the recipient underneath a portion of the recipient&#39;s skin/muscle/fat, collectively referred to herein as tissue  219 . The reservoir  202  may be positioned between layers of the recipient&#39;s tissue  219  or may be adjacent to a subcutaneous outer surface  229  of the recipient&#39;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 ). 
     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. 
     The reservoir  202  includes a needle port (not shown) so that the reservoir  202  can be refilled via a needle injection through the skin. 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. The reservoir  202  may have a preformed shape and the reservoir is implanted in this shape. 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 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. Reservoir  202  may have other shapes as needed to operate with hearing prostheses, as will be detailed below by way of example and not by way of limitation. 
     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. 7 , the distal end  214  of the delivery tube  206  is fluidically coupled to the recipient&#39;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 . 
       FIGS. 5-7  illustrate a system that utilizes 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 this system, 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 some implementations of the system of  FIG. 5 , positioning of the reservoir  202  adjacent the superior portion of the mastoid provides a surface that is sufficiently rigid to counter 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 . 
       FIGS. 5 and 6  illustrate a specific arrangement in which the reservoir  202  includes a resiliently flexible wall  220 . It is to be appreciated that the reservoir  202  can 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, 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. 
     External force is applied on the tissue  219  adjacent to the reservoir  202  to create the external force. As will be described below, in some embodiments, an external vibratory device of a passive transcutaneous bone conduction device that vibrates to evoke a hearing percept is pressed onto the soft tissue  219  under which the reservoir  202  is located. The movement (e.g., oscillation/vibration) of the actuator causes deformations the reservoir  202  to create the pumping action that propels the treatment substance out of the reservoir. 
     Internal and/or external magnets and/or magnetic materials may be used in the arrangements of  FIGS. 5 and 6  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. 
     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. 6 ). 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 . 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. 
     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). 
     As noted, the treatment substance (sometimes herein referred to as therapeutic 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 therethrough in one direction only. This assures that released treatment substances do not back-flow into the reservoir  202 . 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 system of  FIGS. 5 and 6 , the valve is responsive to a magnetic field generated by external magnet  210 . As such, the valve  204  will 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 . 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 . 
     The use of a stop-check valve can 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. 
     The use of a magnetically activated stop-check valve is merely exemplary and that other types of valves may be used. For example, 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 some instances, manually applied (e.g., finger) force be also able to open the valve  204 . 
     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. 
     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. 
       FIGS. 5-7  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.  FIGS. 5-7  also illustrate that the reservoir  202  is positioned adjacent to the outer surface  229  of the recipient&#39;s skull so that an external force may be used to propel the treatment substance from the reservoir. 
       FIG. 8  illustrates an implantable delivery system  800  that is different than system  200  in at least one way in that the delivery system  800  circulates fluid into and out of the cochlea  140  so as to disperse a therapeutic substance therein. As with system  200 , system  800  can utilize a passive or an active actuation system. Any device, system, and/or method that will induce circulation of the fluid into and out of the cochlea can be utilized in at least some embodiments. Here, the system  800  includes a mixer housing  802 , some more specific features of which will be described in greater detail below. As can be seen, a delivery tube  206  and a return tube  806  extend from the mixer housing  802 . Like reference numbers will be utilized with respect to system  200 . A valve  205  alternately opens and closes fluid communication between the proximal end  213  of return tube  806 . In an exemplary embodiment, an impeller system is utilized to generate the circulatory flow. By way of example only and not by way of limitation, located in housing  802  can be an impeller driven by electric motor that drives fluid into delivery tube  206  and/or located in housing  802  can be an impeller driven by electric motor that drives fluid out of tube  806 . Some additional details of these features will be described in greater detail below. 
     In the embodiment of  FIG. 8 , the housing  802  positioned within the recipient underneath a portion of the recipient&#39;s skin/muscle/fat, collectively referred to herein as tissue  219 , and can be positioned as reservoir  202  is positioned above. As will be detailed below, the housing  802  can be positioned elsewhere, and, with respect to a modified embodiment of the housing  802 , the housing  802  can be positioned in the middle ear. 
     Any treatment substance as detailed above with respect to reservoir  202  can be utilized or otherwise contained in housing  802  for mixing with the perilymph from the cochlea. Indeed, any one or more features detailed above with respect to reservoir  202  can be present with respect to housing  802  in at least some embodiments (and vice versa). 
     As seen, the proximal end  213  of the return tube  806  is fluidically coupled to the housing  802  via the valve  205 , which can correspond to valve  204  and have the same functionality thereof or different functionality (e.g., preventing flow out of the housing  802  instead of into the housing  802 ). In an alternate embodiment, there is no valve  205 , and the tube is directly connected to the housing and/or the valve  205  is away from the housing (there are two tube segments, with the valve in the middle). As shown in  FIG. 8 , the distal end  215  of the return tube  806  is fluidically coupled to the recipient&#39;s oval window  122 . Unlike the embodiment of  FIG. 5 , there is no delivery device  208  disposed within the distal end  214  of the delivery tube  206  which is positioned abutting the oval window  122 . Instead, the delivery tube  206  is in fluid communication with the interior of the cochlea. As described further below, the return tube  806  may be secured within the recipient so that the distal end  215  remains located adjacent to the oval window  122 . 
     In some embodiments, as will be described in greater detail below, the distal ends of the tubes can be configured to penetrate through the oval and round windows into the cochlea to establish fluid communication between the respective ducts of the cochlea and the respective tubes by way of direct fluid flow (as opposed to, for example, osmosis or diffusive flow). Accordingly, in an exemplary embodiment, the delivery devices at the ends of the tubes are valves or the like and/or are flanged ports that couple to the cochlea. In some embodiments, the delivery devices extend through the round and oval windows in a manner that seals the round and oval windows between the inner circumference thereof and the delivery devices. Again, additional features of such will be described in greater detail below. That said, it is noted that while some embodiments are directed towards the utilization of intrusive mechanical coupling devices to secure the delivery system to the cochlea, in some alternate embodiments, nonintrusive coupling devices, such as clamps, glues, etc. can be utilized. It is noted that in some embodiments, the tubes are intentionally positioned to avoid contact with any structure of the cochlea or even the human at the tip of the tubes and/or along their length back to the opening into the cochlea. That is, the tube extends like a quasi-cantilever beam in the cochlea, supported by the opening into the cochlea/wall between the middle ear and the inner ear. This can have utilitarian value with respect to minimizing any deleterious effect on hearing (e.g., due to contact with the membranes and/or walls in the cochlea duct(s)—thus, in an exemplary embodiment, the method of insertion avoids the aforementioned insertion as well—that it, the tip and the length behind the tip never contacts the inside of the cochlea—in some embodiments, no part of the device in the cochlea contacts the tissue therein save for the location at the opening, for at least 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 40, 50, 60, 70, 80, 90, 100 days, weeks, months or years). 
     The embodiment of  FIG. 8  permits the circulation of a fluid into and out of the cochlea, where, a therapeutic substance is entrained or otherwise mixed into the fluid that is circulated into and out of the cochlea. Additional details of the entrainment/mixing of the therapeutic substance are detailed below. However, for the moment, focus will be upon the circulation of fluid, where it is to be understood that in at least some exemplary embodiments, the circulation of fluid can include the therapeutic substance therein, while in other embodiments, the circulation of fluid does not include the therapeutic substance therein (i.e., it is at least substantially all perilymph) and/or the circulation of fluid may include a therapeutic substance therein, but at the particular time frame of interest, there is no therapeutic substance being added to the fluid. 
     It is noted that in an exemplary embodiment, the system is configured to be located in part, in the middle ear and, in part, at a retroaurical position (e.g., the reservoir can be located at that position), and/or, in part, in the cochlea. 
     With respect to the circulation of fluid,  FIG. 9  depicts a high-level conceptual view of this concept, where arrow  401  represents fluid flow from tube  206  through the round window  121  into the cochlea in general, and into the tympanic duct in particular. The fluid travels along fluid flow path  421  until it reaches the apical portion of the cochlea, and then transitions into the vestibular duct (e.g., for example, at the heliotrema) and then travels along fluid flow path  422  and then exits through the oval window  122 , and thus into tube  806 , as represented by arrow  402 . 
       FIG. 10  presents a functional conceptual view of the principle of operation of the circulation of fluid through the cochlea, with respect to a functional view of a cochlea,  140 X. In  FIG. 10 , the delivery tube  206  delivers fluid, which can include the active substances detailed herein or does not include such substances. The delivery of fluid into the cochlea is represented by arrow  401 , which represents fluid being directed through the round window  121 X. The fluid flow in the cochlea constitutes two parts. The first being the fluid flow in the tympanic duct  421 X, and the second being the fluid flow in the vestibular duct  422 X. These flows being bifurcated by structure of the cochlea that bifurcates these two ducts, conceptually represented by  441 X. As can be seen, once the fluid flow reaches the apical portion of the cochlea, the fluid begins its return trip back to the delivery system  800 . The fluid exits the cochlea  140 X at the oval window  122 X, as represented by arrow  402 . 
     It is briefly noted that while the embodiments presented above have focused upon fluid flow where the fluid enters the cochlea at the round window and exits the cochlea at the oval window, in an alternative embodiment, this is reversed. In this regard, tube  206  can be utilized to deliver fluid through the oval window  122  and tube  806  can be utilized as the return of fluid through round window  121 , as respectively represented by arrows  4002  and  4001  in  FIG. 11 . Note further that in some exemplary embodiments, the system  800  is configured to reverse the direction of fluid flow through the respective tubes, depending on the temporal period of use of the system. In this regard,  FIG. 12  conceptually represents a scenario where the direction of fluid flow is reciprocally changed over time, as represented by arrows  40001  and  40002 . In this regard, tube  206  can be a delivery tube in some instances, and a return tube in other instances, and tube  806  can be a return tube in some instances, and a delivery tube and other instances. It is noted that this reversal of fluid can occur after a period of, for example, at least after 1 minute, 1.5 minutes, 2 minutes, 2.5 minutes, 3 minutes, 3.5 minutes, 4 minutes, 5 minutes, 6 minutes, 7 minutes, 8 minutes, 9 minutes, 10 minutes, 11 minutes, 12 minutes, 13 minutes, 14 minutes, 15 minutes, 20 minutes, 25 minutes, 30 minutes, 40 minutes, 50 minutes, 60 minutes, 70 minutes, 80 minutes, 90 minutes, 100 minutes, 110 minutes, 120 minutes, 2.5 hours, 3 hours, 3.5 hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 11 hours, 12 hours, 15 hours, 20 hours, 24 hours, or more, of fluid flow in one direction. In at least some exemplary embodiments, the reversal of flow occurs in a cyclic period that does not evoke a hearing percept or otherwise did not evoke a distracting hearing percept in the recipient to the extent that the recipient retains any residual hearing. 
     In some embodiments, fluid entering the cochlea, unless a flow is created, will be moved through cochlea by diffusion only, rather than by a traditional concept of flow. By way of example, if a molecule is placed in the base of tympani, the movement of the molecule will be random, but it may eventually find the way to the base of vestibuli. If one places a statistically significant number of molecules therein, some of them will arrive at vestibuli base at some point, but the arrival time will still be random. If there is a concentration gradient, this will eventually be removed, by the process of diffusion. Some embodiments utilize diffusion, while others use flow, while others use a combination of such. 
     It is noted that some embodiments include a surgical technique where, in the event that cochlea fluid has escaped, CSF is replaced in the cochlea. As will be explained in greater detail below, the CSF can be removed and replaced with cochlea fluid, which might have been captured at the escape time (the escape could have been controlled, and guided into a temporary container). Also, the introduction of CSF can create a longitudinal flow between the cochlea aqueduct and the site of the perforation 
       FIG. 13  presents an exemplary functional somatic of fluid circulation into and out of the cochlea and into and out of system  800  according to an exemplary embodiment. As can be seen, in this embodiment, tubes  206  and  806  extend into the cochlea. In this regard, in an exemplary embodiment, there is no discrete interfacing component per se. In this exemplary embodiment, the tubes  806  and  206  are sized and dimensioned so as to fill the space of the oval and round windows and/or the space of the hole therein (which may not take up the entire space of the oval and round window—it is the surgical opening that is filled) so that the fluid in the cochlea cannot escape or otherwise does not leak out in substantial amounts. That is, while the embodiment of  FIG. 13  depicts an opening between the tubes  806  and  206  and the structure of the cochlea  140 X, in at least some exemplary embodiments, there is no opening. However, as will be described in greater detail below, in some embodiments, separate interfacing components are located at the distal ends of the tubes that interface with the cochlea and provide a seal between the windows and the components of the delivery system. Any arrangement that can enable utilitarian fluid circulation into and out of the cochlea can be utilized in at least some exemplary embodiments. 
     It is also noted that while the embodiment of  FIG. 13  and the embodiments depicted so far present utilization of the round and oval windows as the entry and exit ports, in some alternate embodiments, one or more cochleostomys are utilized to provide fluid communication between the delivery system  800  and the cochlea. By way of example only and not by way of limitation, in an exemplary embodiment, the round window is utilized to place the delivery system into fluid communication with the tympanic duct, and a cochleostomy to the vestibular duct is utilized so as to maintain the oval window membrane. Alternatively, by way of example only and not by way of limitation, the oval window is utilized to place the delivery system into fluid communication with the vestibular duct, and a cochleostomy to the tympanic duct is utilized so as to maintain the round window membrane. Still further, by way of example only and not by way of limitation, respective cochleostomys to the tympanic duct and the vestibular duct are utilized to respectively bypass the round and oval windows and maintain the membranes thereof in place. Any arrangement that can be utilized to access the inside of the cochlea to establish fluid flow herein can be utilized in at least some exemplary embodiments. 
     Still with reference to  FIG. 13 , it can be seen that the fluid flow out of the cochlea from the oval window becomes fluid flow  1422  and travels down the return tube  806  to the housing  802 . The fluid flow then reverses direction and becomes fluid flow  1421  and travels out of the housing  802  and then travels down delivery tube  2062  to the cochlea, where the fluid flow becomes  421 X upon reintroduction into the cochlea. 
     In an exemplary embodiment, mixing housing  802  can include a powered pump or the like that induces the circulation flow. Accordingly, in at least some exemplary embodiments, the system is an active system. Some additional details of this will be described below. That said, in an alternative embodiment, the system is a passive system, where the circulation is established via any one or more of the scenarios detailed above with respect to system  200 . By way of example only and not by way of limitation, housing  802  can include a flexible portion where the recipient can repeatedly press thereupon so as to pump the fluid into and out of the cochlea. Again, some additional details will be described below. It is noted that in some embodiments, there is a flow limiting device, such as a flow limiting valve, that limits flow into the cochlea and/or out of the cochlea to a safe and/or utilitarian level. In an exemplary embodiment, the flow limiter limits flow to a rate of no more than 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.25, 2.5, 2.75, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20 ul/hour, at least for embodiments where there is no replacement fluid being affirmatively introduced (e.g., something more than natural diffusion/introduction of CFS). In an exemplary embodiment, the device is configured to limit flow into and/or out of the cochlea to ensure that the difference between the normal amount and the actual amount of fluid therein, for a 25 to 75 percentile human factors engineering human of the age of which the implant is provided, which human can be a citizen of the United States, the EU, UK, the Federal Republic of Germany, the Republic of France, the Republic of Italy, and/or Japan and/or the People&#39;s Republic of China, to a flow rate that would reduce and/or increase the volume of fluid at any given time by no more than 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.25, 2.5, 2.75, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20 percent of that which was present before the commencement of flow. 
     There can be utilitarian value with respect to simply circulating fluid into and out of the cochlea, irrespective of whether the fluid contains therein a therapeutic substance, such as an active drug. That said, in some embodiments, there is utilitarian value with respect to circulating a fluid through the cochlea that includes an active drug or other therapeutic substance. In this regard,  FIG. 14  depicts an exemplary embodiment where an active therapeutic substance  1422  is entrained or otherwise injected into the fluid flow flowing into and out of the cochlea. More specifically, in the embodiment of  FIG. 14 , mixing housing  802  includes a reservoir and mixing system  1422  that releases an active substance  1424  into the fluid flow flowing into and out of the cochlea. In an exemplary embodiment, reservoir and mixing system  1422  includes a reservoir and a piston and valve arrangement that meters one or more doses of therapeutic substance out of the reservoir and mixing system  1422  into the fluid flow, and thus the mixing system  1422  can be considered an injection system. In an alternate embodiment, the reservoir and mixing system  1422  entails a porous chamber containing an active substance and the system  1422  permits the active substance to leach out of the system  1422  into the fluid flow. In alternative embodiment, the reservoir and mixing system  1422  entails a porous chamber containing an active substance, but the system  800  is configured such that the fluid flow flows into and out of the system  1422 , at least a portion of the active substance dissolves into the fluid flow, which then leaves the system  1422  and exits out housing  802  into tube  206  for delivery to the cochlea. In an alternative embodiment, the reservoir and mixing system  1422  is a system that mechanically dispenses solid pellets containing an active substance out of a housing via a conveyor belt into the fluid flow stream, where the pellets dissolve while in fluid flow  1421  while in tube  206 . Any arrangement of introducing an active substance into the fluid flow circulating into and out of the cochlea can be utilized in at least some exemplary embodiments. It is noted that this is but an example, and other embodiments can utilize a different delivery regime. 
     Still with reference to  FIG. 14 , it can be seen that the active substance  1424  is entrained or otherwise next with the circulating fluid flow in housing  802 . The active substance  1424  travels down tube  206  with flow  1421 . The former is represented by the wide triangles, and the latter is represented by the long triangles.  FIG. 14  conceptually depicts how the active substance gradually is removed from the fluid flow as the fluid flow travels through the cochlea. As can be seen, the wide triangles progressively become smaller and smaller with distance from the introduction point into the cochlea. This represents the tissue of the cochlea absorbing the therapeutic substance as the fluid flow travels through the cochlea. In at least some exemplary embodiments, the ratio of therapeutic substance to the non-therapeutic or otherwise non-active substance of the fluid flow is such that by the time the fluid exits the cochlea or otherwise enters return tube  806 , there is little to no therapeutic substance left in the fluid flow because it has been absorbed by the tissue. In an exemplary embodiment, the absorption is uniform such that all areas of the cochlea absorb about the same amount of therapeutic substance. That said in some alternate embodiments, the absorption is not uniform such that some areas of the cochlea absorb more of the therapeutic substance than other areas. By way of example only and not by way of limitation, in an exemplary embodiment, such as where an electrode array of a cochlear implant has been inserted into the tympanic duct, and/or where the actuator of a direct acoustic cochlear stimulator (DACS) has been inserted into the tympanic duct, more therapeutic substance can be absorbed at those locations than in the vestibular duct. That said, in some alternate embodiments of the aforementioned implant regimes, the absorption of the therapeutic substance is uniform. 
     It is also noted that in at least some exemplary embodiments, the amount of therapeutic substance that is introduced into the fluid flow is such that the ratio of therapeutic substance to the non-therapeutic substance/non-active substances of the fluid flow remains substantially unchanged over the single circulation into and out of the cochlea. In this regard, in an exemplary embodiment, the amount of therapeutic substance that is added to the fluid flow is so large that for a given circulation, the tissue of the cochlea can only absorb so much of the therapeutic substance. Such an exemplary scenario is depicted in  FIG. 15 , where the sizes of the wide arrows do not change. This is not to say that the ratio does not change with respect to the single circulation into and out of the cochlea. The ratio does change because the tissue does absorb some of the drug, but only a relatively small amount relative to the amount of drug in the fluid. 
     Note also that while the embodiments detailed above have been directed towards the ratio of therapeutic substance to non-therapeutic substance/non-active substance in the fluid flow, in an exemplary embodiment, the ratio may not change because the tissue absorbs both the therapeutic substance and the non-therapeutic substance that creates the fluid flow. Alternatively, and/or in addition to this, the ratio may change but only because the amount of active substance that is absorbed is different than the amount of an active substance that is absorbed. 
     With respect to the embodiment of  FIG. 15 , in at least some exemplary scenarios, the fluid flow is circulated a number of times (this concept can be also applicable to the embodiment of  FIG. 14  as well). Each time that the fluid flow is circulated, a certain amount of the therapeutic substance is absorbed by the tissue of the cochlea. Thus, each circulation can provide a new “dose” of therapeutic substance to the tissue. Indeed, in this regard, the depiction of  FIG. 15  can represent a “slug” of therapeutic substance that is only located in a portion of the total fluid flow, where the slug moves into and out of the cochlea with circulation. In this regard, in an exemplary embodiment, with respect to a single circulation, the slug may only be present in the cochlea for half the time, three quarters of the time, one quarter of the time, etc. It is noted that by the term “slug,” it is not meant a solid object. Instead, it is analogous to, for example, a dye marker in the ocean or the like. That said, in some alternate embodiments, the slug can be a solid object. Any arrangement of providing a therapeutic substance in a limited amount with respect to the overall fluid flow can utilize in at least some exemplary embodiments. 
       FIGS. 16, 17, 18, and 19  conceptually depict movement of a limited slug through the cochlea with respect to a given partial circulation. As can be seen, the slug of therapeutic substance  1424  moves through the cochlea with fluid circulation to the cochlea. In at least some exemplary embodiments, as the slug of therapeutic substance  1424  travels in the cochlea, the local tissue of the cochlea absorbs some of the therapeutic substance. 
     In an exemplary embodiment, the circulation occurs only partially, at least with respect to a given temporal period. By way of example only and not by way of limitation, in an exemplary embodiment, the circulation can begin so that the slug is moved out of tube  206  into the cochlea, and then out of the cochlea into tube  806 . In an exemplary embodiment, the circulation continues until the slug again reaches housing  802 . At this point, in an exemplary embodiment, the circulation is stopped for a given period of time. In an exemplary embodiment, the given period of time is a period of time for the efficacy of the therapeutic substance that has been absorbed by the tissue to be lowered so that another dose of therapeutic substance has utilitarian value. By way of example only and not by way of limitation, six hours after the slug has been passed through the cochlea, and the circulation has been shut down, the circulation is reactivated, and the slug is again passed to the cochlea, thus treating the tissue, and upon the slug returning to the housing  802 , the circulation is shut down again for another period of time and so on. 
     It is noted that in an exemplary embodiment, the system  800  can be such that the slug can be recaptured by reservoir and mixing system  1422  and thus taken out of the fluid flow. In an exemplary embodiment, this can have utilitarian value with respect to embodiments where the fluid flow continues even without the therapeutic substance in the fluid. That said, in an exemplary embodiment, this can have utilitarian value with respect to embodiments where, for example, not all of the slug has mixed with the fluid, but some of the slug has mixed with the fluid, and some of the slug that has mixed with the fluid has not been absorbed by the tissue. In this regard, the slug can be recaptured by system  1422  and removed from the fluid flow, such that additional therapeutic substance is no longer being imputed into the fluid flow, but the fluid flow is continued to be circulated such that the therapeutic substance that has been dissolved or otherwise mixed with the fluid flow can be repeatedly circulated through the cochlea. In an exemplary embodiment, whether by sensor or by estimation or by empirical analysis, or by statistical analysis, upon a determination that the therapeutic substance that was mixed with the fluid flow has been substantially absorbed by the cochlea and/or otherwise the amount of therapeutic substance mixed with the fluid flow is no longer sufficient for efficacy, the slug can then be again introduced into the fluid flow and then removed, but the fluid flow can continue circulating. Corollary to this is that in an exemplary embodiment, instead of a slug per se, the system  1422  periodically releases an active substance into the fluid flow, which would not necessarily result in a discrete slug, but would instead result in a quasi-uniform distribution of therapeutic substance into the fluid flow, and then halts the release of active substance in the fluid flow while the fluid flow continue circulating into and out of the cochlea. This can have utilitarian value with respect to metering or otherwise providing control doses of the active substance. Any arrangement of introducing or otherwise managing the amount of therapeutic substance in the fluid flow can be utilized at least some exemplary embodiments. 
     As noted above, some exemplary embodiments of the therapeutic substance delivery system can correspond to a device that is configured so as to fit entirely into the middle ear and/or into the middle and inner ear.  FIG. 20  depicts such an exemplary embodiment, where delivery system  2000  is a compact device that includes a housing  2002  having inlet and outlet ducts  2806  and  2206  respectively (or vice versa, or, in embodiments where the flow can be reversed, inlet/outlet ducts  2806  and  2206 ). In an exemplary embodiment, the components of the delivery system  2000  that are located outside of the cochlea proper (where the outer surface of the cochlea that faces the middle ear is part of the cochlea) are all configured to be located entirely in the middle ear cavity. In this regard, instead of the elongate and/or flexible tubes of the system  800  detailed above, here, the ducts of the system  2000  are relatively short (0.1-20 mm in length) and/or relatively stiff. As with the embodiments of the system  800  above, the ducts  2806  and/or  2206  can be placed in fluid communication with the oval and round windows respectively or variously can be placed into fluid communication with the cochlea via separate cochleostomys associated with the respective ducts. 
     Accordingly, in an exemplary embodiment, the device is configured to be entirely located, collectively, in a middle ear and/or an inner ear of an adult human. 
       FIG. 21  functionally depicts system  2000  interfacing with cochlea  140 X, and also the fluid flow resulting from operation of the system  2000 , along with the entrainment of the therapeutic substance  1424  in housing  2002 . 
     As noted above, there can be utilitarian value with respect to the therapeutic substance delivery systems being able to close the openings into the cochlea. In this regard,  FIG. 22  depicts an exemplary embodiment of a delivery system  2200 , which includes a series of O-rings  2210  extending about ducts  2806  and  2206 . In an exemplary embodiment, the O-rings are compressible and fill up the holes through the wall of the cochlea through which tubes  2806  and  2206  extend, thereby establishing a leak-proof or at least a substantially leak-proof seal between the system  2200  and the wall of the cochlea. In an exemplary embodiment, the O-rings  2210  are sized and dimensioned to completely fill the round window and/or the oval window. In an alternate exemplary embodiment, the O-rings  2210  are sized and dimensioned to completely fill the holes established via a cochleostomy. 
       FIG. 23  depicts an exemplary embodiment of a delivery system  2300  which utilizes an adapter  2220  to take up a space between the outer diameter of the tube  2206  and the wall of the cochlea through which tube  2206  extends. In this regard, the outer diameter of  2206  is relatively small relative to the passageway into the cochlea (e.g. through the round or oval window or through the resulting cochleostomy). At least some exemplary embodiments of O-rings  2210  do not have sufficient size to completely fill the hole between the tube  2206  and the wall of the cochlea. Accordingly, adapter  2220  takes up the difference in the space. The embodiment of  FIG. 23  makes clear that different connections can be utilized with respect to the same delivery system.  FIG. 23  also makes clear that different size tubes can be utilized. In the embodiment of  FIG. 23 , it can be seen that the return  2806  has a larger diameter than the input tube  2206 . This can have utilitarian value with respect to ensuring that the limiting factor to fluid flow is the input path into the cochlea as opposed to the output path out of the cochlea, thus decreasing the possibility of a deleterious pressure rise within the cochlea. That said, in some alternate embodiments, the diameter of the input to can be larger than the diameter of the output tube. Any arrangement that can have utilitarian value with respect to coupling the delivery system to the cochlea and/or establishing fluid flow through the cochlea in a utilitarian and safe manner can be utilized in at least some exemplary embodiments. 
       FIG. 24  presents an alternate embodiment of a delivery system, delivery system  2400 , that utilizes a flange  2420  that abuts the outside of the cochlea. In an exemplary embodiment, flange  2420  includes an adhesive that bonds to the outside of the cochlea and thus establishes a seal between the cochleostomy and/or the window and the middle ear. In an exemplary embodiment, the flange  2420  remains entirely outside the cochlea. That said, in an alternate embodiment, the flange  2420  can be of a configuration where the flanged can be collapsed or otherwise deformed to fit inside the cochlea and then expand inside the cochlea and thus abut the inside wall of the cochlea to establish a seal. Still further, in an exemplary embodiment, there can be an outer flange and an inner flange which sandwich the wall of the cochlea to establish a seal on the inside and the outside. In an exemplary embodiment, this can be an interference fit vis-à-vis the flanges. Indeed, in this regard, the tubes  2806  and/or  2206  can be interference fitted through the holes through the cochlea to establish a seal. The embodiment of  FIG. 24  also provides an alternative embodiment that seals the tubes relative to the cochlea. In this regard, groove  2410  is located on tube  2206 . In an exemplary embodiment, groove  2410  is sized and dimensioned so as to essentially snapfit into the hole into the cochlea. Owing to the resiliency of the material of tube  2206 , the groove  2410  establishes a seal between the inside of the cochlea and the middle ear. In a sense, groove  2410  operates based on a similar principle of operation of the dual flanges  2420  just described above, except where is the flange extends outward away from the tube, the groove  2410  extends inward from the outer surface of the tube. 
       FIG. 25  presents yet another alternate embodiment of a seal arrangement. Here, there is groove  2510 . In this embodiment, groove  2510  is configured such that there are relatively sharp edges or otherwise pointed edges at the outer radial position of tube  2206 , this owing to the fact that the width of the groove  2510  grows larger with respect to distance from the outer circumference of tube  2206 . Because the relatively sharp edges or otherwise pointed edges at the outer periphery of the groove  2510 , the outer periphery of group  2510  digs into the tissue that establishes the cochlea wall through which tube  2206  extends. In an exemplary embodiment, the groove  2510  is sized and dimensioned so as to establish a seal. Note further that in an exemplary embodiment, an O-ring can be located in groove  2510  or groove  2410  for that matter, which O-ring can be resilient, which can further enhance sealing. 
     As can be seen, system  2500  further includes an alternate embodiment of a flanged  2520  that includes spiked anchors at the outer periphery thereof. In an exemplary embodiment, the spikes dig into the wall of the cochlea that separates the cochlea from the middle ear so as to dig in or otherwise hold the flange  2520  against the outer wall of the cochlea. It is noted that in an exemplary embodiment, an O-ring  2560  can be located inboard of the flange  2520  which can abut the outer wall of the cochlea and/or or fit in the hole through which tube  2806  extends to further seal the cochlea (the ring  2530  can be a stepped ring so that a portion thereof fits into the hole, and a portion thereof fits outside the hole on the outer surface of the outside wall the cochlea. It is also noted that while the embodiment of  FIG. 25  depicts the anchors facing inboard, alternatively and or in addition to this, the anchors can face outboard, such as in the embodiment where the collapsible flange expands after being inserted in the cochlea, and then the system  2500  is pulled back a bit so that the anchors can dig into the outer wall of the cochlea from the inside. 
     It is noted that the embodiment of  FIG. 25  along with some of the other embodiments just detailed depicts different embodiments for the respective tubes to establish the respective seals. It is noted that in some embodiments, both tubes can utilize the same seals while in other embodiments the tubes can utilize different seals. Any of the seals can be mixed and matched or any of the features of the seals can be mixed and matched and otherwise combined providing that such is enabled by the art and such has utilitarian value. 
     Thus, in an exemplary embodiment, the device is configured to extend from an outside of the cochlea to at least an interior of the cochlea and secure itself to the cochlea at a location proximate the location of extension to the at least an interior of the cochlea. By way of example only and not by way limitation, barbed spikes on flange  2520  can be located within 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 millimeters of the cochleostomy (from the geometric center or the geometric edge). 
       FIG. 26  depicts yet an alternate embodiment of a delivery system  2600  that utilizes a shroud  2610  extends about the respective tubes. As can be seen, no part of the system  2600  extends into the cochlea. In an exemplary embodiment, an adhesive or the like is located on the outer edges of the shrouds  2610 . Thus, in an exemplary embodiment, the device is configured to extend from an outside of the cochlea to at least a location proximate an opening into an interior of the cochlea and secure itself to the cochlea at a location at or proximate the location into an interior of the cochlea. 
     In view of the above, it can be seen that in an exemplary embodiment, there is a device, such as a prosthesis, that includes a drug delivery device, such as by way of example only and not by way of limitation, systems  800 ,  2000 ,  2200 ,  2300 ,  2400 ,  2500 , and/or  2600  configured to simultaneously interface with a scala tympani and a scala vestibuli of a cochlea. Still further, it can be seen that in some embodiments, the device is configured to induce complete circuit circulation from the scala tympani to the scala vestibuli and/or vice versa, thereby distributing drug within the cochlea. In this regard, it is noted that in at least some exemplary embodiments of the delivery system  200  detailed above, in some instances, the therapeutic drug or other therapeutic substance delivered to the cochlea congregate or otherwise pool at the basal portion of the cochlea, or at least a substantial amount thereof, relative to the amount that reaches the apical portion. In this regard, with respect to the turns of the cochlea, it is possible that in at least some exemplary scenarios, the amount of drug that reaches the area after the X° turn of the cochlea with respect to the given duct into which the therapeutic substance is initially delivered may be Y less than that which reaches tissue before the X° turn. In an exemplary embodiment, X is 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 325, 350, 375, 400, 425, 450, 475, or 500. In an exemplary embodiment, Y is 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 96, 97, 98, 99, or 100%. Thus, it can be understood that in at least some exemplary embodiments, Y can be very much. This can have less than maximum utilitarian results in that portions of the cochlea may not be efficaciously treated by the therapeutic substance, such as the portions beyond the X° turn. 
     Alternatively, with respect to the embodiments herein that utilize circulation or otherwise induce circulation, because the therapeutic substance is driven with the fluid flow, at least partially, much more of the substance can be delivered to the more apical portion of the cochlea. Moreover, much more of the therapeutic substance can be delivered to the opposite duct relative to the duct into which the therapeutic substance is directly introduced (e.g., if the drug is introduced into the vestibular duct, the duct receiving deficient or otherwise less therapeutic substance would be the tympanic duct, and vice versa). Indeed, in some exemplary scenarios of utilization of the system  200 , little to no therapeutic substance will reach the opposite duct. 
     In at least some of the exemplary embodiments utilizing the circulation, the amount of drug that reaches the area after the X° turn of the cochlea with respect to the given duct into which the therapeutic substance is initially delivered is more than A of that which reaches tissue before the X° turn. In an exemplary embodiment, A is 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 96, 97, 98, 99, or 100%. Thus, it can be understood that in at least some exemplary embodiments, the amount of drug that reaches the area after the turn at issue is substantially or otherwise effectively the same as that which reaches the portion of the cochlea before the turn. Thus, in at least some exemplary embodiments, the teachings herein utilizing circulation can deliver about the same amount of drug to all areas of the cochlea regardless of location, or at least with respect to the area between the inlet and the egress of the fluid flowing into and out of the cochlea. In any event, in at least some embodiments where the device is a therapeutic substance delivery device, the device is configured to drive the therapeutic substance to a juncture of the scala tympani and the scala vestibuli. In an exemplary embodiment, the device is configured to drive the therapeutic substance to a juncture of the scala tympani and the scala vestibuli in an amount that is at least about or is about 99, 98, 97, 96, 95, 94, 93, 92, 91, 90, 89, 88, 87, 86, 85, 84, 83, 82, 81, 80, 75, 70, 65, 60, 55, or 50% of the amount that first enters the cochlea or any value or range of values therebetween in 0.1 percent increments. In an exemplary embodiment, the device is configured to drive the therapeutic substance to a juncture of the scala tympani and the scala vestibuli in an amount that is an effective amount with respect to treating tissue at that juncture. In an exemplary embodiment, the driving starts at the basal region of the cochlea, such as, by way of example only and not by way limitation, at a location at or proximate the round window and/or the oval window. 
     As can be seen above, such as with respect to systems  800 ,  2000 ,  2100 ,  2600 , etc., the device can include a fluid inlet and a fluid outlet respectively configured to be placed into fluid communication with, respectively, the scala tympani or the scala vestibuli, and/or vice versa. Also as can be seen by these exemplary embodiments, the device can be configured to permanently simultaneously interface with a scala tympani and a scala vestibuli of a cochlea so as to enable, respectively, ingress and egress and/or vice versa of perilymph from/to the cochlea during the period of permanent interfacing. By way of example only and not by way of limitation, it is noted that in an exemplary embodiment, the systems detailed herein are configured to “tap” the cochlea to enable the natural perilymph to be flowed out of the cochlea and into the system. In this regard, the fluid flow to which the therapeutic substances are added can be a fluid flow of perilymph. In at least some exemplary embodiments, it is a natural perilymph that is utilized. That said, in some alternate embodiments, the fluid flow can be a combination of a natural perilymph and a perilymph equivalent that is a non-active substance. Any arrangement of fluid that can be combined with an active or otherwise therapeutic substance to enable the teachings detailed herein can be utilized at least some exemplary embodiments. In this regard, by way of example only and not by way of limitation, in an exemplary embodiment, the systems detailed herein can be configured with a reservoir of active substance and separate reservoir of a non-active substance. The reservoir of non-active substance can be utilized to provide additional fluid of the fluid flow, and the reservoir of active substance can be utilized to provide the active substance that is entrained into the fluid flow. In an exemplary embodiment, the system can be configured so as to separately access the separate reservoirs when there is utilitarian value with respect to adding additional non-active substance and/or active substance. In an exemplary embodiment, the system is configured such that the active substance can be mixed with the non-active substance prior to introduction of the mixture into the fluid flow. Alternatively, in some alternate embodiments, the system is configured such that the active substance is mixed directly with the fluid flow and the non-active substance is separately mixed with the fluid flow. Alternatively, in some alternate embodiments, the system is configured such that the active substance and the non-active substance can be mixed simultaneously with the fluid flow. 
     Thus, in an exemplary embodiment, the aforementioned device can be configured to extract perilymph from the cochlea, mix the drug with the extracted perilymph, and insert the mixture into the cochlea. Also, in an exemplary embodiment, the device is configured to move a non-perilymph substance from external to the cochlea to inside the cochlea via the circulation. As noted above, in at least some exemplary embodiments, the non-perilymph substance can be a therapeutic substance such as, by way of example only and not by way of limitation, a drug. That said, in some alternate embodiments, the non-perilymph substance can also be a non-therapeutic substance. 
     It is noted that while the embodiments above have focused on a system that delivers a fluid flow to the cochlea and removes the fluid flow from the cochlea at the basal portion of the cochlea, in an alternative embodiment, the removal and/or delivery can be located at another location. In this regard,  FIG. 27  depicts an exemplary delivery system where the delivery tube  206  extends through the round window  121 X such that flow  421 X extends through only one duct of the cochlea (the tympanic duct in this embodiment, where in alternative embodiments, it could be the vestibular duct). As can be seen, tube  27806  interfaces with the apical portion and/or helicotremaof the cochlea such that the fluid flow exits the cochlea at arrow  402  and becomes fluid flow  1422 , wherein tube  27806  extends to the housing  2702 , which housing can functionally correspond to the housing  802  detailed above, etc. Accordingly, fluid is circulated through the cochlea, but only a portion thereof. It is noted that while the embodiment of  FIG. 27  depicts the tube  27806  interfacing at the apical portion of the cochlea (where, in some embodiments, that tube can be a return tube while in other embodiments, that tube can be a delivery tube), in an alternate embodiment, tube  27806  can interface at a another location of the cochlea prior to the apical portion (i.e., between, with respect to the spiral of the cochlea, the basal portion and the apical portion with respect to a given duct) or after the apical portion. By way of example only and not by way of limitation, in an exemplary embodiment, tube  27806  can interface with the cochlea, such as via a cochleostomy, at a location at about at the turn Z°, where, in an exemplary embodiment, Z is 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 325, 350, 360, 375, 400, 425, 450, 475, 500, 525, 550, 575, 600, 625, 650, 675, 700, 725, 750, 775, 800, 810, 820, 830, 840, 850, 860, 870, 871, 872, 873, 874, 875, 876, 877, 878, 879, 880, 881, 882, 883, 884, 885, 886, 887, 888, 889, 890, 891, 892, 893, 894, 895, 896, 897, 898, 899, or 900, 901, 902, 903, 904, 905, 906, 907, 908, 909, 910, 911, 912, 913, 914, 915, 916, 917, 918, 919, 920, 925, 930, 935, 940, 945, 950, 955, 960, 965, 970, 975, 980, 990, 1000, 1050, 1100, 1150, 1200 degrees or any value or range of values therebetween in 0.25° increments (e.g., 48.5°, 92°, 56 to 293 degrees, etc.—it is noted that on average, there are 2.5 turns of the cochlea, but that is just an average). 
     In an exemplary embodiment, the second cochleostomy where tube  27806  interfaces with the cochlea can be at any location between the apical portion and the basal portion of the cochlea with respect to any of the ducts. In an exemplary embodiment, the second cochleostomy can be located at any location of about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 325, 350, 375, 400, 425, 450, 475, 500, 525, 550, 575, 600, 625, 650, 675, 700, 725, 750, 775, 800, 810, 820, 830, 840, 850, 860, 870, 871, 872, 873, 874, 875, 876, 877, 878, 879, 880, 881, 882, 883, 884, 885, 886, 887, 888, 889, 890, 891, 892, 893, 894, 895, 896, 897, 898, 899, or 900 degrees from the apical portion of the cochlea to the basal portion of the cochlea or any value or range of values therebetween in 0.25° increments (e.g., 77.25°, 92°, 56 to 293.75 degrees, etc.). 
     Accordingly, in an exemplary embodiment, one or more of a first turn and/or second turn cochleostomy can be utilized to access the cochlea. It is also noted that in an exemplary embodiment, utilization of an access location of the cochlea at a location away from the basal location can utilize the fact that the fluid flow can flow downstream or otherwise downward with respect to gravity, corollary to this is that in at least some exemplary embodiments, some scenarios of use and thus some embodiments can include devices to enable at least partial removal of perilymph of fluid from the cochlea and then the introduction of fluid at a “higher” location, and because there is less perilymph in the cochlea, including no perilymph or substantially no perilymph, the fluid introduced at the higher location with the therapeutic substance will flow downward. Accordingly, in an exemplary embodiment, there is a method that includes at least partially reducing or otherwise removing perilymph from the cochlea, including emptying the cochlea of perilymph, and then introducing/reintroducing the perilymph including the therapeutic substance into the cochlea at a higher location and allowing the fluid containing the therapeutic substance to flow downward, thus exposing various locations of the cochlea to the therapeutic substance. 
     In any event, in at least some exemplary embodiments, flow can be achieved via a single port. By way of example only and not by way of limitation, in a modified embodiment of system  200 , the delivery tube  206  can be both a delivery the tube and a return tube. In an exemplary embodiment, modified system  200  can be configured to suck perilymph out of the cochlea. In an exemplary embodiment, the perilymph is partially or completely sucked out of the cochlea or otherwise removed from the cochlea, then entrained with a therapeutic substance, and then reintroduced into the cochlea, where the therapeutic substance is generally evenly dispersed within the fluid that is reintroduced into the cochlea, or at least otherwise contains an effective distribution of therapeutic substance such that most if not all of the portions of the cochlea will be treated with a therapeutic substance. 
     In an exemplary embodiment, there is of a reservoir that is part of the device that receives perilymph that is extracted from the cochlea. In an exemplary embodiment, the implant is configured to extract perilymph from the cochlea at a relatively low rate, that permits the backfill through natural introduction of CFS (cerevial spinal fluid). Upon taking a desired amount of perilymph out of the cochlea, and entraining or otherwise mixing the therapeutic substance therein, the cochlea is then refilled with the perilymph from the reservoir, and the CFS is thus expelled, in whole or in part, from the cochlea. In an exemplary embodiment, the inflow of perilymph at one end of the cochlea can expel the CFS out the other end. The end result may be that at the end of the reinsertion of the perilymph, 70, 75, 80, 85, 90, or 95 percent of the fluid in the cochlea is perilymph, and the remaining is CFS (so as to reduce the likelihood that the perilymph will be expelled out the exit). That is, in an exemplary embodiment, perilymph is siphoned from the cochlea, and then replaced in the cochlea. That said, in an exemplary embodiment, CFS can be the medium that is introduced into the cochlea, such as in a scenario where the perilymph has been depleted (e.g., a so called “gusher” occurs during surgery). That is, in an exemplary embodiment, CFS in what is used to refill the cochlea. Indeed, in an exemplary embodiment, CFS can be affirmatively introduced to the cochlea, as opposed to relying on natural diffusion. This can enable an increase in the flow rates of perilymph into and/or out of the cochlea beyond those detailed above. 
     It is also noted that in some embodiments, the tube  206  can also interface the cochlea at a location other than the basal portion. In an exemplary embodiment, any of the aforementioned turns can be a location where a cochleostomy can be present and the tube  206  can interface there with. Any location of accessing the cochlea that can enable the circulation can be utilized in at least some exemplary embodiments. 
     Thus, in view of the above, the aforementioned device can be configured to interface with at least one of the scala tympani or the scala vestibuli at a location at or above a first turn, a 1.25 turn, a 1.5 turn, a 1.75 turn, a second turn, a 2.25 turn or a 2.5 turn of the cochlea. 
     With respect to the teachings detailed herein with respect to a prosthesis configured to circulate perilymph within a cochlea, in an exemplary embodiment, such a prosthesis can be as seen above, a drug delivery system or the like. It is briefly noted that in at least some exemplary embodiments, the prosthesis can also include components configured to evoke a hearing percept, such as by way of example only and not by way limitation, a cochlear implant and/or a direct acoustic cochlear stimulator, etc. Some additional details of such will be described in greater detail below. 
     Still consistent with the teachings detailed above, in an exemplary embodiment, the prosthesis includes a device that is configured extract perilymph from the cochlea, mix a non-perilymph substance with the extracted perylimph (e.g., a therapeutic substance, such as by way of example only and not by way of limitation, a perilymph soluble drug), and insert the mixture into the cochlea. 
     As noted above, in at least some exemplary embodiments, the circulation systems detailed herein can include a pump configured to drive the circulation of the perilymph. In an exemplary embodiment, this can be an impeller. In an exemplary embodiment this can be a turbine. In an exemplary embodiment, these components can be driven by an electrical source of the like. In an exemplary embodiment, these components can be driven by manual force input along the lines of that detailed above with respect to system  200 . In an exemplary embodiment, these components can be driven via a magnetic field or the like along the lines of that detailed above with respect to system  200 . Any device, system and/or method that will enable the circulation can be utilized at least some exemplary embodiments. 
     It is noted that the embodiment of  FIG. 20  can have utilitarian value with respect to limiting or otherwise minimizing the amount of perilymph that is removed from the cochlea at any given time. In this regard, the embodiments of system  800  can require or otherwise result in more perilymph being removed from the cochlea than that of the embodiment of system  2000 . In this regard, by way of example, this is because tubes  806  and  206  are substantially longer than ducts  2806  and  2206 . Indeed, in an exemplary embodiment, the device is configured such that when the device is attached to a cochlea, the device establishes a fluid path from the scala vestibuli to the scala tympani outside the cochlea in at least substantially the shortest path possible. 
     By way of example only and not by way of limitation, in an exemplary embodiment, the fluid path from a first opening into the cochlea to a second opening into the cochlea is no more than 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30 mm. 
     That said, at least some embodiments are such that the system expands a perilymph containing volume within the recipient beyond that established by the cochlea. In an exemplary embodiment, the volume is expanded by amount of B, where B is about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 25, 30, 35, 40, 45, 50, 55, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, 115, 120, 125, 130, 135, 140, 145, 150, 155, 160, 165, 170, 175, 180, 190, 200, 210, 220, 230, 240, or 250%. In an exemplary embodiment, the volume is expanded by no more than amount of B. In an exemplary embodiment, the volume is expanded by more than an amount of B. It is noted that while this embodiment is disclosed in relation to embodiments that provide therapeutic substance into the cochlea, in some alternate embodiments, such can be utilized independent of such a feature, such as, by way of example only and not by way of limitation, to simply reduce and/or increase pressure inside the cochlea and/or to enable an artificial hearing percept to be evoked utilizing a hearing prostheses. 
     To be clear, embodiments can include a means for interfacing with a cochlea, and a means for distributing a therapeutic substance within a cochlea. In some embodiments, the means for interfacing with the cochlea includes a means for establishing separate fluid communication between the scala tympani and an outside of the cochlea and a scala vestibuli and the outside of the cochlea. In at least some embodiments, the means for distributing the therapeutic substance within the cochlea is also a means for distributing the therapeutic substance effectively equally within the cochlea. In at least some embodiments, the device includes a shunt that establishes fluid communication from the scala tympani to the scala vestibuli of the cochlea. In an exemplary embodiment, the device induces fluid flow from the scala tympani to the scala vestibuli, and/or vice versa, of the cochlea. 
     As noted above, at least some exemplary embodiments of the therapeutic substance delivery systems described herein and/or variations thereof can be utilized in conjunction with a hearing prosthesis. In this regard,  FIG. 28  functionally depicts an exemplary scenario where the delivery system  800  is utilized in conjunction with a cochlear implant, as represented by lead  145  and electrode array  146  being located in cochlea  140 X. In this exemplary embodiment, a separate cochleostomy  120 X is provided in the cochlea to access the scala tympani. This separate cochleostomy is separate from the round window  121 X, as can be seen. That said, in an exemplary embodiment, the same access port can be utilized for both the delivery system  800  and the cochlear implant. In an exemplary embodiment, a seal arrangement and/or coupling arrangement can be provided that separately seals tube  206  relative to the access port and electrode array  146  or related component relative to the access port.  FIG. 29  depicts an exemplary embodiment of a seal-coupling component  2910  in the form of a circular disk, although in other embodiments, the component  2910  approaches a cylindrical like depth (into/out of the page), and in other embodiments, the component  2910  has a cylindrical depth. In an exemplary embodiment, the component  2910  is fit into a circular cochleostomy that provides an access port to the tympanic duct or the vestibular duct. The component  2910  is configured to seal against the cochlea wall with respect to the outer circumference thereof. As can be seen, component  2910  includes two holes  2920  and  2930  which extend completely through the component  2910 . In an exemplary embodiment, holes  2920  and  2930  provide access for the particular tube of the delivery system and the array of the cochlear implant. In an exemplary embodiment, those components have seals that seal the insides of the holes  2920  and  2930  and/or the component  2910  has a seal that seals the holes when the tubes and the array interface therewith or otherwise are placed proximate therewith. In an exemplary embodiment, component  2910  also provides an anchor or the like for the particular tube of the delivery system and/or the cochlear implant. 
     Note also that in an exemplary embodiment, there can be an apparatus that holds both tubes in place and/or also holds the cochlear implant electrode array and/or provides seals for the respective tubes.  FIG. 30  depicts an exemplary embodiment of such an apparatus  3010 . Apparatus  3010  can include the aforementioned disk and/or cylinder and or partial cylinder as noted above, and can also include arm  3040  which extends therefrom to clip  3050  which is configured to hold the other tube in place. In this embodiment, the interference fit established by the disk/cylinder is utilized to hold the apparatus  3010  in place. In an alternate embodiment, a bone screw or the like is utilized with respect to arm  3040 . Moreover, in an exemplary embodiment, there can be a component that is configured to simply hold the tubes and or the electrode array in place, where the sealing features of the respective tubes and/or the associated components therewith and/or the sealing features of the electrode array and/or the associated components therewith are utilized to seal the cochlea.  FIG. 31  depicts such an exemplary embodiment. Here, clip  3050  is connected to an arm  3040  which is configured to be connected to the outer wall of the cochlea via bone screw  3110 . Arm  3040  is also connected to boss  3131  through which hole  3120  is located, through which a tube of the delivery system extends. In this exemplary embodiment, the boss  3131  interference fits with the tube to hold the tube relative to the fixation component. Also as can be seen, a clip  3150  attached to an arm that extends from boss  3131  is also present, which clip can be utilized to hold the cochlear implant electrode array in place. In some embodiments, one or more of these features may not necessarily be present, and in other embodiments, some of the features are substituted for some of the other features (e.g., clips are utilized to hold all components, etc.). 
     While the embodiments detailed above have focused upon the delivery system being a separate component/separate system from the hearing prostheses system, in an exemplary embodiment, the two systems are instead subsystems of a system that includes both. In this regard,  FIG. 32  depicts the cochlear implant electrode array extra-cochlear portion physically attached to the tube  206 . In an exemplary embodiment, both subsystems are implanted at the same time. 
     Note also that while the embodiments detailed above have focused on separate ports into the cochlea to access the cochlea for the respective tubes and the cochlear implant electrode array, an alternate embodiment, the cochlear implant electrode array and the delivery system are combined in a manner that enables access into the cochlea through a single port.  FIG. 33  depict such an exemplary embodiment, where tube  206  is in fluid communication with a conduit within the electrode array  146  (not shown) that extends into the cochlea with the electrode array  146 , which electrode array  146  includes an orifice on a side of the electrode array so as to enable fluid communication between the tube  206  and the tympanic duct. 
     In view of the above, it is to be understood that in at least some exemplary embodiments, there is a method, which includes driving an effective amount of a therapeutic substance to an apical region of the cochlea. In an exemplary embodiment of this method action, by way of example only and not by way of limitation, such can be executed utilizing system  800  as detailed above, where the circulation of fluid containing the therapeutic substance into the tympanic duct or into the vestibular duct, to the apical region, and then into the other of vestbular duct or the tympanic duct, can result in an effective amount of the therapeutic substance being driven thereto. This as opposed to a scenario where, for example, the therapeutic substance is provided into one of the ducts via system  200 , for example, where the therapeutic substance may pool or otherwise remain at the basil portion of the given duct, or, in some alternative scenarios, where natural or even man-made fluid flow resulting from the introduction of the therapeutic substance into the cochlea may drive or otherwise bring a modicum of the therapeutic substance to the apical region, but such will not be an effective amount. 
     In an exemplary embodiment, the action of driving the effective amount of the therapeutic substance to the apical region is executed in a number of times. By way of example and only and not by way of limitation, such is executed with each circulation, where the circulation can occur H times, where H can be one, two, three, four, five, six, seven, eight, nine, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 20, 29, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, or 200, or 225, or 250, or 275, 300, 350, 400, 450 or 500 or more times or any value is a range of values therebetween in 1 increment. It is noted that in an exemplary embodiment, the aforementioned number of circulations can be based on a single dose. That is, in an exemplary embodiment, by way of example only and not by way of limitation, the reservoir and mixing system can “inject” or otherwise entrain a dose of a therapeutic substance into the fluid flow, and then the fluid is circulated H number of times, and then another dose is injected or otherwise entrained into the fluid flow. This can be repeated H number of times in some embodiments. 
     Note also that in some exemplary embodiments, the therapeutic substance can ultimately become diffused evenly or otherwise substantially evenly in the fluid flow, or otherwise can be diffused such that all parts are substantially all parts of the fluid flow contain an amount of therapeutic substance that will be effective in treating the tissue. In an exemplary embodiment, the circulation can occur for a given period of time until the therapeutic substance is effectively distributed in the fluid flow, at which point the circulation can be halted. In an exemplary embodiment, such can be based on empirical and/or statistical data. In this regard, in an exemplary embodiment, a sensor can be provided that can sense the presence and/or determine the amount of therapeutic substance in the fluid flow. Moreover, in an exemplary embodiment, the amount of time it takes for the fluid to completely circulate through the system and through the cochlea can be known, based on, statistical and/or empirical data (e.g., markers can be projected or otherwise entrained into the flow), and the amount of therapeutic substance can be metered so as to evenly distribute or otherwise effectively evenly distribute the amount of therapeutic substance into the flow. Upon a determination that the therapeutic substance is evenly distributed or otherwise effectively distributed within the cochlea, the circulation is shut down. 
     It is also noted that the aforementioned circulation(s) can occur within a given temporal period. Accordingly, in an exemplary embodiment, there is a method that entails circulating fluid through the cochlea H number of times within 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 20, 29, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 225, 250, or 275, 300, 350, 400, 450, or 500 seconds or minutes or hours, depending on the utility and the enablement and the efficacy of doing such. 
     Corollary to the above, it can be understood that in an exemplary embodiment, there is a method that includes the method actions of tapping a cochlea at a first location, which first location can be at the round window, at the oval window, or at a cochleostomy at the basil portion of the cochlea, or a cochleostomy at a location away from the basil portion of the cochlea, such as any of the locations detailed herein or other locations that can have utilitarian value. The method further includes the action of tapping the cochlea at a second location away from the first location, which can include, for example, tapping the cochlea at the other of the round or oval window, or at a cochleostomy according to any of the teachings detailed herein or other locations that can have utilitarian value. It is noted that the first location and the second location can be a location that both leads to the tympanic duct or the vestibular duct. The method further includes inserting a component of a prostheses, such as electrode array of a cochlear implant or a mechanical stimulator of a DACS, etc., into the cochlea at the first tapped location. The method also includes the action of at least one of inputting drug or another type of therapeutic substance into the cochlea or removing drug or the another type of therapeutic substance out of the cochlea using fluid flow through the second tapped location. In an exemplary embodiment of the aforementioned method, the tapped location where the drug or other therapeutic substance is inputted and/or removed can be a location away from a basal end of the cochlea, such as, for example, at the second turn, the 1.5 turn, or in any of the angular locations detailed herein or other locations that can have utilitarian value. 
     As will be understood as detailed herein, in an exemplary embodiment, the tapped location where the drug or other therapeutic substance inputted is a location away from a basal end of the cochlea. It is also to be understood that in some exemplary embodiments, a third tapping can be executed at a third location away from the first and second locations. This third tapping can be for the return of the fluid circulated out of the cochlea. That said, as detailed above, such as where a single tap is utilized for both the hearing prosthesis and the delivery and/or return of fluid, in an exemplary embodiment, there are only two locations that are tapped. (To be clear, the embodiment of  FIG. 33 , for example, which depicts the electrode array as being utilized to deliver the fluid into the cochlea, can be used, in an alternate embodiment as the return of fluid from the cochlea (or both, with respect to the embodiments where the fluid flow can be reversed)). 
     While the embodiments detailed above have typically focused on circulating perilymph or another fluid into and out of the cochlea, in at least some alternative embodiments, the utilitarian value associated with fluid circulation is executed without the fluid leaving the cochlea. That said, in at least some exemplary embodiments, while embodiments detailed above with respect to circulating a fluid flow into and out of the cochlea of focused on circulating the fluid from the tympanic duct and then out of the cochlea and then to the vestibular duct or vice versa, in some embodiments, fluid is flown out of the tympanic duct into the middle ear, and then flown back into the tympanic duct and then into the vestibular duct and then into the middle ear and/or then back into the vestibular duct and then into the tympanic duct and then into the middle ear and then back into the tympanic duct and so on, and this can be repeated a number of times. 
     In an exemplary embodiment, there is a therapeutic substance delivery system configured to artificially flow perilymph within the cochlea from the scala tympani to the scala vestibuli and then back from the scala vestibuli to the scala tympani and/or vice versa, so as to distribute the therapeutic substance within the cochlea. In an exemplary embodiment of this exemplary embodiment, the fluid exits the cochlea and then reenters the cochlea, while in other embodiments, the fluid never leaves the cochlea, at least with respect to a given circulation regime. 
     In at least some exemplary embodiments, the delivery system is configured to establish a circulation via the use of an implanted impeller or the like that is implanted into the cochlea that circulates the fluid, and thus the therapeutic substance, as just detailed. Also, in an exemplary embodiment, the impeller can be located in the middle ear, where, for example, fluid is removed from the cochlea from one of the vestibular duct or the tympanic duct, mixed with a therapeutic substance in the middle ear, and then reinserted into the cochlea at that same duct from which it was removed, where the system is configured to flow the fluid and thus the entrained therapeutic substance from the one duct to the other, or at least to the apical portion of the cochlea. In some embodiments, the delivery system is configured to flow the fluid from the other duct back to the original duct of entrance, and so on, and this can be repeated a number of times so as to distribute the therapeutic substance. 
     Moreover, in at least some exemplary embodiments, there is a method that includes a method action of establishing perilymph flow at least one of into or out of the cochlea and establishing perilymph flow the other of into or out of the cochlea at another location from the aforementioned first and second locations, thereby driving the effective amount of the therapeutic substance to the apical location. Also, in an exemplary method, there is a method action of establishing perilymph flow at least one of into or out of the cochlea at a first location and establishing perilymph flow the other of into or out of the cochlea at a second location away from the first location, thereby driving the effective amount of the therapeutic substance to the apical location. The first and second locations can be the same as the first and second locations detailed above or can be different. Also, in some embodiments of the methods herein, the method(s) are such that the established flow is established via an extra cochlea fluidic pump system that extends from the first location into the middle ear of the recipient back to the cochlea to the second location, wherein the pump system is located in the recipient for at least or for U hours, where U is 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 20, 29, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 225, 250, or 275, 300, 350, 400, 450, 500, 550, 600, 650, 700, 800, 900, 1000, 1110, 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900, 2000, 2250, 2500, 2750, 3000, 3500, 4000, 4500, 5000, 6000, 7000, 8000, 9000, 10000, 15000, or 20000 or any value or range of values therebetween in 1 increment. 
     Moreover, in at least some exemplary embodiments of the methods detailed herein, the methods include the method action of artificially flowing perilymph within the cochlea from the scala tympani to the scala vestibuli and/or vice versa for at least or for U minutes in total, thereby driving the therapeutic substance to the apical location. In some embodiments, the aforementioned established flow is an artificial perilymph circulation from the scala tympani to the vestibuli, out of the cochlea and then back into the cochlea and/or visa-versa. In some embodiments, this circulation occurs for at least or for U hours in total. 
     In view of the above, it is to be understood that in at least some exemplary embodiments, there are methods of and devices for artificially distributing a therapeutic substance within the cochlea beyond that which results from diffusion distribution. In this regard, system  200  operates on the principle of diffusion distribution. In system  200 , a therapeutic substance is delivered into the cochlea, and then permitted to diffuse within the perilymph, so as to treat tissue within the cochlea. In an exemplary embodiment, the diffusion is analogous to a die marker released by a swimmer the like in the ocean: it is the die that flows within the ocean water. Moreover, in some embodiments where the perilymph does not flow from one duct into the other duct, osmosis or the like through the structure of the cochlea, such as through the Reissner&#39;s membrane, are relied upon to treat other portions of the cochlea, such as tissue within a duct that the fluid flow does not directly flow therein. In contrast to this, by driving the fluid from one duct to the other and/or by driving the fluid from one end of the duct, such as the basal end, to a more apical portion of the duct, the therapeutic substance is distributed beyond only diffusion distribution. To be clear, in at least some exemplary embodiments, diffusion is relied upon to distribute the therapeutic substance within the fluid, which will at least partially results in the distribution of the therapeutic substance within a limited portion of the cochlea. By driving the fluid and otherwise inducing the circulation of the perilymph into and out of the cochlea and/or within the cochlea, that diffused therapeutic substance which is diffused into the fluid is driven to other locations of the cochlea that would otherwise not be visited by the therapeutic substance/fluid-therapeutic substance mixture. 
     Accordingly, in an exemplary embodiment, there is a therapeutic substance delivery device that is configured to deliver drug to the cochlea at least in part via a post introduction non-diffusion based delivery. 
     As noted above, some embodiments utilize a mixer reservoir. As will be understood, in at least some exemplary scenarios of use, the reservoir might become depleted of the therapeutic substance contained therein or otherwise reach a level where further efficacious distribution of therapeutic substance to the cochlea will not be utilitarian feasible. To recharge or otherwise refill the reservoir (or other component(s) of the given delivery system), any of the teachings detailed above vis-à-vis system  200  can be utilized in at least some exemplary embodiments. That said, any other system of recharging or otherwise refilling the reservoir or other component(s) of the delivery system can utilize in at least some exemplary embodiments. 
       FIG. 34  represents an exemplary embodiment that has utilitarian value with respect to recharging or otherwise refilling the mixer reservoir. Here, delivery system  3400  includes a mixer reservoir  3422 , which is exposed fluidically to the middle ear environment  106 . In this regard,  FIG. 34  conceptually depicts the inner boundaries of the middle ear. In an exemplary scenario, the reservoir  3422  is recharged or otherwise refill by placing the therapeutic substance adjacent the reservoir  3422  and permitting the therapeutic substance to enter the reservoir  3422  via some form of transfer mechanism, such as, for example, a controllably openable close the valve, a pump arrangement that sucks material from inside the middle ear cavity into the reservoir, and osmosis system or the like. 
     In an exemplary scenario, the therapeutic substance is delivered into the middle ear cavity, and the reservoir absorbs other rise up takes the therapeutic substance.  FIG. 35  depicts an exemplary scenario where the middle ear cavity  106  is filled or substantially filled with a therapeutic substance, or, a carrier of the therapeutic substance, where the therapeutic substance is uptaken into the reservoir  3422 . By way of example only and not by way of limitation, a gel or the like that supports or otherwise holds the therapeutic substance therewith can be inserted into the middle ear cavity so that the gel interfaces with the reservoir  3422 . The reservoir  3422  or other component of the system  3400  uptakes the therapeutic substance (e.g., by utilization of an osmotic membrane that extracts the therapeutic substance from the gel, by electrolysis that extracts the therapeutic substance from the gel, etc.) and charges or otherwise refill the reservoir with the therapeutic substance. This is conceptually presented by way of example in  FIG. 36 . 
     Thus, in view of the above, it can be seen that in an exemplary embodiment, there is a method that can include the actions of attaching a therapeutic substance delivery device at a tapped location of the cochlea prior to inputting drug into the cochlea, subsequently depleting an amount of therapeutic substance of the delivery device, and then subsequently recharging the delivery device with more therapeutic substance via saturation of a local environment of the delivery device. In an exemplary embodiment, the saturation can be by a material that is purely the therapeutic substance, while in other embodiments, the saturation can be by a mixture of the therapeutic substance in some other carrier substance. 
       FIG. 37  depicts another exemplary embodiment of a conduit system  3737  which places the tympanic duct and the vestibular duct into fluid communication with each other outside the cochlea. In an exemplary embodiment, owing to the dual paths for the two ducts to communicate with one another, natural circulation can occur into and out of the cochlea. In this regard, in an exemplary embodiment, the system is a passive system with respect to enabling circulation into and out of the cochlea. It is further noted that in an exemplary embodiment, the conduit system  3737  may not necessarily include or otherwise be directly associated with the therapeutic substance. In an exemplary scenario, a therapeutic substance is separately injected or otherwise inserted into the cochlea, and then subsequently, the conduit system  3737  is attached to the cochlea, and the natural circulation that occurs distributes the therapeutic substance within the cochlea. Still further, in an exemplary scenario, the conduit system  3737  is first attached to the cochlea, and then the therapeutic drug is inserted into the cochlea, or otherwise inserted into the now expanded volume of the perilymph containing fluid. In this regard, in an exemplary embodiment, the conduit system  3737  is made of a material that can be penetrated by a syringe or the like. In an exemplary scenario, a syringe is utilized to pierce or otherwise gain access to the interior of the conduit system  3737 , whereby the syringe is utilized to inject the therapeutic substance into the conduit system  3737 , where the circulation associated there with ultimately distribute therapeutic substance within the cochlea. That said, in an alternate embodiment, by way of example only and not by way of limitation, the conduit system  3737  can include a component that is specially configured to receive the syringe/needle of the syringe. By way of example only and not by way of limitation, an apparatus that is akin to the drug containing vials that have the pierceable container tops can be located at, for example, a base of the conduit system  3737 . 
     That said, in an alternate embodiment, the conduit system  3737  can have a tap or the like where the therapeutic containing substance can be attached so that the therapeutic substance can be inserted into the conduit system. In this regard,  FIG. 38  presents an exemplary embodiment where tap  3837  is located at the geometric center of the conduit system  3737 . Tap  3837  is threaded so as to receive mail threads of a syringe. In an exemplary embodiment, the syringe is screwed onto tap  3837 , establishing a seal therebetween, and then the syringe is depressed to inject the therapeutic substance in the conduit  3737 . In an exemplary embodiment, a male threaded cap (not shown) is subsequently screwed onto the tap  3837  to seal or otherwise closer the system. In an exemplary embodiment, on a determination that there is utilitarian value with respect to re-providing therapeutic substance, the aforementioned male threaded cap is unscrewed to obtain access to the interior of the conduit system  3737 , and then a syringe is then subsequently screwed onto the mail threads of the tap  3837 , and then the therapeutic substances then injected therethrough, and then the cap is replaced. Still, it is noted that in some alternate embodiments, element  3837  can instead be a membrane or the like that is pierceable by a needle and then subsequently closed in a hermetic or semi hermetic fashion or at least in a manner that resists leakage of the fluid therethrough. 
     While the embodiments detailed above relies on threads to secure the cap to the conduit system, in an alternate embodiment, a press fit or an interference fit or the like can be utilized to secure the cap to the conduit system and/or to secure the syringe to the conduit system. Any arrangement that can enable the transfer of therapeutic substance from the syringe to the conduit system and/or any arrangement that can seal the conduit system can utilize in at least some exemplary embodiments. 
       FIG. 39  depicts an exemplary embodiment where the reservoir is removably replaceable from the conduit system  3737 . Here, tap  3937  is configured to interface with reservoir  3910 . In an exemplary embodiment, reservoir  3910  is configured to be removably replaceable from  3937 . In this embodiment, reservoir  3910  is configured to establish a seal around the outer circumference of  3937 . In this embodiment, the therapeutic substance contained in reservoir  3910  is configured to defuse into the stream of fluid flowing through conduit system  3737  and passed the tap  3937 . That said,  FIG. 40  depicts an exemplary embodiment where the tap  4037  is configured with a barrier wall  4038  that directs the fluid flow into the reservoir  4010 , and thus more affirmatively commingling the perilymph with the bioactive substance contained in the reservoir  4010 . In an exemplary embodiment, the cap (not shown) is configured to accommodate the barrier  4038  such that there is a space between the end of the barrier  4038  and the cap so that fluid can travel there around. That said, in some embodiments, reservoir  4010  is a semi-permanent part of the system, and is removed and replaced when the therapeutic substance therein is been depleted. 
     In at least some exemplary embodiments, a replaceable bolus of therapeutic substance is utilized to charge the delivery system. 
     Conversely, in another embodiment, the barrier  4038  is part of the reservoir  4010 , and is removed when the reservoir is removed. 
       FIG. 41A  depicts an exemplary embodiment that includes about  4150  that permits the controllably opening and closing of a fluid path from the scala tympani to the scala vestibuli and/or vice versa. In this exemplary embodiment, a knob  4160  is present that enables a surgeon or other healthcare professional to open and close the valve  4150 . That said, in an alternate embodiment, a clamp or the like can be utilized to collapse the conduit  3737  and into on collapse the conduit  3737 , thereby respectively preventing fluid flow and enabling fluid flow. Any device, system, and/or method of controllably opening and closing the fluid path from the respective ducts can be utilized at least some exemplary embodiments. 
       FIG. 41B  depicts another exemplary embodiment parallel to the embodiment of  FIG. 41A  but includes a second valve at the reservoir port, as can be seen. Thus, in an exemplary embodiment, there is a means for distributing a therapeutic substance that includes a passageway extending from the scala vestibuli to the scala tympani that includes one or more valves to at least one of controllably open and close a fluid path from the scala tympani to the scala vestibuli and/or vice versa or permit a reservoir containing the therapeutic substance to be placed into and out of fluid communication with the passageway thereby enabling removal of a reservoir from the passageway while maintaining a closed fluidic system of the device. 
     In an exemplary embodiment, there is a system that includes one or more valves that open for delivery of drug, close for the replacement of drug loading, and then open again for subsequent delivery. It is noted that in some embodiments, the valves are part of the device that couples the ducts together, while in other embodiments, the valves are part of the reservoir/removable/replaceable device that contains the therapeutic substance. 
       FIG. 42  depicts another embodiment of a device configured to circulate fluid.  FIG. 42  depicts an actuator assembly  1361 . Here, there is tube  771  that interfaces with one side of the cochlea and is in fluid communication with one of the ducts, which leads to chamber  791 , which is separated from chamber  792  by barrier  793 ′. The actuator includes displacement cylinders  1391  and  1392 . The cylinders include pistons  1391 ′ and  1392 ′ that move in an alternating manner in and out (or, more precisely, towards and away) from chambers  791  and  792  respectively, thus varying the total volume of those chambers. As can be seen, a lever arrangement  1393  is utilized, where a single actuator  1321  drives the movement of the pistons  1391 ′ and  1392 ′ in an equal but opposite manner. That said, in an alternate embodiment, two separate actuators can be utilized to independently drive the two pistons in an alternating manner. In this regard, a control circuit such as a programs computer chip that controls the actuation of the actuators can be utilized to control the actuation of the separate actuators so as to achieve the dual actuation. Note further, that while the embodiment depicted in  FIG. 42  utilizes two separate pistons, in an alternate embodiment, a single piston can be utilized, where the piston is manifolded to the two chambers  791  and  792  such that movement of the piston in one direction displaces fluid into a given chamber while displacing fluid from the other chamber and vice versa. Any arrangement that can enable the fluidic teachings detailed herein and/or variations thereof to be practiced can be utilized in at least some embodiments. Also, as will be detailed below, embodiments also include non-fluidic embodiments, and thus any arrangement that can enable the principles of operations detailed herein and/or variations thereof to be practiced can be utilized in at least some exemplary embodiments. 
     In the embodiment of  FIG. 42 , the diameter of the piston is approximately the same as the diameters of the tubes  771  and  781 , and thus there is no hydraulic amplification. That said, in alternative embodiments, the diameters can be larger or smaller to achieve hydraulic amplification and/or hydraulic deamplification. 
     Thus, in an exemplary embodiment, the actuator assembly is configured to respectively displace the fluids in the chambers  791  and  792  by controllably moving the pistons  1391 ′ and  1392 ′, thereby generating positive and negative pressure differentials within the chambers. As can be seen, flap valve  4221  is located at the end of tube  771 , and is configured to move in the direction of arrow A 421 . Also, flap valve  4222  is located at the passageway between chamber  791  and  792  and is configured to move in the direction of arrow A 422 . With the device of  FIG. 42 , the fluid can be circulated into and out of the cochlea. Not shown is a fluidic coupling with a reservoir of drug or the like that can be utilized to inject drug into one of or both of the chambers (or in some embodiments, the pistons are utilized to suck the drug into the chambers). 
     In view of the above, it can be seen that in some embodiments, there is a device, such as a perilymph fluid shunt, etc., which can have couplings to locations of perilymph or endolymph which can allow or otherwise enable or assist flow between the two locations. In some embodiments, the perilymph can then be mixed with an active substance, which can be liquid, solid, encapsulated cells etc. In some embodiments, the flow between the two locations is driven as a result of an active device or the like or otherwise by a pump or the like. That said, in other embodiments, a semi-natural circulation can result owing to the fact that there are two routes from the tympanic duct to the vestibular duct and vice versa. Any device that can enable the artificial connection of the ducts, such as a cannula, a fluid shunt, a tube apparatus, etc., can be utilized in at least some exemplary embodiments. 
     Note also that in some embodiments, the active therapeutic substance can be embedded in the shunt that connects the two ducts. In an exemplary embodiment, the active therapeutic substance can exude into the fluid flow. By way of example only and not by way of limitation, the shunt can include a porous interior surface in which the therapeutic substance can be located. In an exemplary embodiment, the shunt or other apparatus that connects the respective ducts houses the therapeutic substance in a particular discreet area thereof, such as at an entrance and/or an exit of the shunt/other apparatus. 
     In an exemplary embodiment, the shunt or otherwise the delivery system is replaceable in its entirety or in part. By way of example only and not by way of limitation, with respect to a shunt system, where, for example, the drug is embedded into the shunt body, after a period of time, the shunt is removed, and replaced with a new shunt. In an exemplary embodiment, this can be done with respect to the artificial components in their entirety, or otherwise can be done with respect to only a subcomponent so as to not disturb the components that directly interface with the cochlea. In this regard,  FIG. 45  depicts an exemplary embodiment where the components that mount directly to the cochlea, duct portions  4537 , remain attached to the cochlea, and the removable subcomponent  4538  is removed along with drug containing body  4545  (if still present), and then replaced with another removable subcomponent  4538  that includes a new charge of the drug containing body. In an exemplary embodiment, valves  4150  are closed prior to removal of the removable subcomponent  4538 . After a new subcomponent  4538  has been attached, the valves are opened again. This way, leakage of perilymph or otherwise flow of fluid in the cochlea can be prevented or otherwise limited while the replaceable component/removable component is replaced. 
     Still further, in an exemplary embodiment, the therapeutic substance can be a solid or a gel or the like that is connected to the interior surface of the shunt, where the solid or gel dissolves or otherwise is entrained into the fluid flow. The therapeutic substance containing perilymph is then redirected into a different part of the scala, whether that be at an apical location or a basal location. Of course, the perilymph can be extracted at an apical region, and redirected into the scale at a basal region. Note also, that apical regions can be utilized for both extraction and return. Thus, the shunt can contain the therapeutic substance. 
     In some embodiments, there is a shunt or other type of apparatus that connects the respective ducts, where the shunt or other type of apparatus is connected to a pump which can deliver drugs, biologics or fluids into the cochlea, either directly or into the shunt. 
     In some exemplary embodiments, the shunt or other type of apparatus can include otherwise contain a micropump, impeller, etc. to encourage fluid flow from one duct to the other and/or of the therapeutic substance into the shunt and/or into the cochlea. 
     In an exemplary embodiment, the shunt or other type of apparatus that connects the respective ducts is a pressure relief device, and thus there is a method of using a shunt or other type of apparatus to relieve intracochlear pressure. In an exemplary embodiment, the shunt is not utilized to deliver therapeutic substance, but instead is used solely and exclusively to relieve intracochlear pressure, and there are also apparatuses that are configured as such for sole use. 
       FIG. 43  presents an exemplary embodiment of an exemplary apparatus that connects the ducts, apparatus  4337 , that includes an expanded volume configured to relieve intracochlear pressure. 
     In an exemplary embodiment, the flow is achieved by a peristaltic manipulation of the passage between the ducts, as seen in  FIG. 44 . Particularly, apparatus  4437  includes a passageway that is surrounded by peristaltic pump  4444  that is configured to compress the passageway in a patterned manner or any other manner that will enable or otherwise induce fluid flow therethrough. In an exemplary embodiment, the shunt or other apparatus that connects the ducts is a discreet component/assembly, and the device(s) used to induce the fluid flow, such as the pumps, etc., are also discreet components/assemblies. In an exemplary embodiment, the pump is clamped around a shunt and manipulates the shunt to achieve flow. 
     While the embodiment of  FIG. 44  presents an embodiment where the passageway is flexible and compressible, in some alternate embodiments, the passageway, such as the shunt, etc., is incompressible. In some embodiments, there is a device that places the ducts into fluid communication with one another, that is configured to vibrate the passageway between the two to achieve fluid movement. In an exemplary embodiment, element  4444  is instead a vibrator. 
     In an exemplary embodiment, flow in the shunt is achieved by a secondary fluid flow from an external pump (air/water/saline). As can be seen, the flow can be achieved by mechanical devices. In some other embodiments, electrical fields, magnetic fields, or heat transfer devices can be utilized. Any device, system, and/or method that can enable the inducement of fluid flow between the ducts can utilize in at least some exemplary embodiments. 
     It is noted that while at least some of the embodiments detailed above are presented in as having tubes/ducts, etc., that interface with the cochlea that have the same interior and exterior diameters respect to both ducts/locations. That said, in an alternate embodiments, the interfacing components can have different interior and exterior diameters. By way of example only and not by way of limitation, in an exemplary embodiment, a portion of the device that interfaces with the cochlea at the basal portion can have a larger diameter than the portion of the device that interfaces with the cochlea at the apical portion, or vice versa. 
     It is noted that in some exemplary embodiments, the access locations to the interior of the cochlear are created utilizing tools, such as drills the like. That said, in some alternate embodiments, the delivery system detailed herein and/or variations thereof can be configured such that they are self-accessing. By way of example only and not by way of limitation, in an exemplary embodiment, the delivery device can have a sharp portions at the end of the tubes that are configured to penetrate the round and oval windows, and can also include the aforementioned seals such that they sell seal when penetrating the round and oval windows. Still further, self-tapping components can be utilized on the components that interface with the cochlea. Note also, in an exemplary embodiment, there is a method where a partial cochleostomy is drilled into the cochlea, but it is not completely drilled into the cochlea, and the delivery device is utilized to “breakthrough” the remaining distance, thus preventing or otherwise limiting the amount of perilymph that escapes from the cochlea. Note also that in some exemplary embodiments, the tubes or otherwise tips of the delivery system can be configured to rotate and thus can be self-tapping. 
     While the embodiments detailed above have been described in terms of accessing perilymph containing bodies of the cochlea, in some alternate embodiments, the teachings detailed herein can be utilized to access the endolymph containing bodies of the cochlea, such as, for example, the cochlear duct. In an exemplary embodiment, the fluid is circulated into and out of the cochlear duct, and the delivery system can access the cochlea at the basil and/or the apical portions or other portions as detailed herein, except with respect to the cochlear duct instead of the other ducts. 
     It is noted that any reference herein to a therapeutic substance corresponds to a disclosure of an active substance such as an active drug or an active biologic etc., and any disclosure herein to an active substance such as an active drug or the phrase active substance in the generic manner corresponds to a disclosure of an active biologic or a therapeutic substance, etc. Any active pharmaceutical ingredient that can have utilitarian value can be a therapeutic substance. Proteins can be therapeutic substances as well. It is also noted that in an at least some exemplary embodiments, an inactive fluid can be a physiological saline, which can be utilized to convey the therapeutic substance into the cochlea. 
     in an exemplary embodiment, therapeutic substance include but are not limited to, any of those detailed above, and can include peptides, biologics, cells, drugs, neurotrophics, etc. Any substance that can have therapeutic features if introduced to the cochlea can be utilized in some embodiments. 
     It is noted that any disclosure of a device and/or system herein corresponds to a disclosure of a method of utilizing such device and/or system. It is further noted that any disclosure of a device and/or system herein corresponds to a disclosure of a method of manufacturing such device and/or system. It is further noted that any disclosure of a method action detailed herein corresponds to a disclosure of a device and/or system for executing that method action/a device and/or system having such functionality corresponding to the method action. It is also noted that any disclosure of a functionality of a device herein corresponds to a method including a method action corresponding to such functionality. Also, any disclosure of any manufacturing methods detailed herein corresponds to a disclosure of a device and/or system resulting from such manufacturing methods and/or a disclosure of a method of utilizing the resulting device and/or system. 
     Unless otherwise specified or otherwise not enabled by the art, any one or more teachings detailed herein with respect to one embodiment can be combined with one or more teachings of any other teaching detailed herein with respect to other embodiments, and this includes the duplication or repetition of any given teaching of one component with any like component. 
     While various embodiments of the present invention have been described above, it should be understood that they have been presented by way of example only, and not limitation. It will be apparent to persons skilled in the relevant art that various changes in form and detail can be made therein without departing from the scope of the invention.