Patent Application
20240033506
The present invention is directed to the area of cochlear implant type surgeries. More specifically, the present invention is directed to a detachable casing device configured to temporarily cover a cochlear implant electrode prior to insertion. There are several advantages associated with the use of a detachable or removable casing. A typical embodiment will provide a surgeon a stiffer, straighter electrode, yielding greater electrode control during insertion; also included are the corresponding apparatuses configured to receive and manipulate such novel electrode casing systems.
Cochlear implants systems are typically recommended in situations where hearing impaired individuals will not obtain any substantial hearing improvements with sound amplifying type hearing aids or devices. A cochlear implant system includes an implantable electrode array configured to directly stimulate the auditory nerve and is inserted into the cochlea of the patient via a delicate surgical procedure. The human cochlea is in the shape of a spiral, beginning at a base and ending at an apex, such a complex geometry, and patent to patent variations thereof, can present insertion challenges to even the best of surgeons. Because of the delicate nature of the various soft tissue structures of the inner ear, numerous types of trauma or injuries can occur during or as a result of cochlear implantation surgery.
Traumatic insertions of an electrode array can result in a variety of injuries. One common injury is damage to the sensory cells associated with the basilar membrane, which will result in a loss of residual or natural hearing. Many investigations describe hybrid hearing as highly beneficial, a condition where residual or natural hearing is substantially superimposed with electric stimulation from the implanted electrode array system. Therefore, it is highly advantageous to preserve as much residual or natural hearing as possible.
Other injuries associated with traumatic electrode insertions include damage to the spiral ganglion cells; the organ of Corti, which houses the sound detecting hair cells; mis-insertion into the scala vestibuli instead of the target scala tympani; perforation the cochlear wall; hemorrhaging; and so forth. Additionally, injuries, immediately following electrode insertion, are also of concern. For example, the unimpeded release of the electrode array leads from the surgical insertion tool, once the electrode insertion process is complete is of significance. Avoidable handling of the electrode array leads and the like, should be minimized/eliminated in order to prevent traumas or injuries linked to the inadvertent transmission of vibrational energy into the sensitive structures of the inner ear.
Cochlear implant systems include electrode arrays possessing a straight configuration, while other arrays are designed to possess a pre-curved shape. Both configurations are fabricated on a flexible type of carrier, such as a silicone polymer, which permits bending within the curved portions of the cochlea. Certain cochlear implant electrode designs, especially those that comprise a pre-curved shape, are manufactured to include a stylet channel, which positioned along the main axis of the insertable portion of the electrode array. A stylet is a substantially thin, ridged instrument, and when housed in its corresponding stylet channel, will tend to both stiffen and straighten electrode array to provide the surgeon with better control with respect to precise electrode array positioning. During one exemplary surgical technique, the electrode array is progressively slid off of the stylet during electrode array insertion into the cochlea. Unfortunately, once the stylet is removed, the corresponding imbedded stylet channel remains as a non-functional feature of the implanted electrode array, needlessly occupying volumetric real-estate within the array. Additional bulk or material must be added to electrode designs that include stylet channel type options.
Consequently, such options drive a tendency toward bulkier, less flexible electrode array designs. The general understanding associated with the reduction of trauma related injuries as it relates to electrode arrays designs corresponds to the size and flexibility of the electrode array. Present day understanding teaches that electrode array related trauma related injuries can be reduced by the introduction of thinner and more flexible arrays.
It is apparent that there are several challenges in cochlear implant arts that long for further improvements. Given our present understanding, there are several paths to optimizing implant hearing outcomes. One path is directed to maintaining the integrity of the cochlear structures, by the elimination/reduction of injury or trauma. Yet other opportunities are based on improvements directed to the advancement of electrode array design and fabrication, as well as supporting the advancement of surgical systems and techniques that further address the preservation of delicate cochlear structures from trauma type injuries.
The present disclosure delineates improvements to cochlear implant devices, tools, and related support systems. In one aspect of the present invention, disclosed is a removable casing or tube that envelops the electrode array, configured to possess a low friction engagement condition between the casing and the electrode array to permit sliding passage of the electrode array through the casing, as well as the safe, complete removal of the casing off of the electrode array. The removable casing in cooperation with a companion surgical tool is configured for the sequential removal of the casing along the major axis of the electrode array as the array being inserted into a Cochlea. The removal of the casing is facilitated by a separator or wedge apparatus comprising the companion surgical tool.
The system can accommodate a variety of removable casing geometries or designs, including slotted casings having a linear opening along the casing's longitudinal profile or main axis; slotted casings devoid of any pre-existing opening—where the two engaging walls comprising the slot, form an elongated slot on at least a portion of the elongated slot; and casings comprising predetermined segments, designed to disconnect or break apart when encountering a separator. The removable casing is configured to temporarily impose straightening forces and stiffen the enclosed electrode array, facilitating a controlled and precise placement of the electrode by the surgeon. In general, the initial condition of the electrode array will temporarily conform to the casing's longitudinal profile. The present invention includes embodiments configured for a variety of electrode array designs, including pre-curved modiolar hugging, straight lateral wall type designs.
Accordingly, it is an object of the present invention to provide a cochlear electrode array casing system and corresponding surgical tool for maneuvering the casing system. The systems are configured to provide improved control over surgical variables associated with the insertion of an electrode array into a cochlea so to minimize implantation trauma. By way of example, but not limitation, surgical variables include electrode array insertion angle or attack angle, electrode array insertion forces with respect to implantation, insertion speed of the electrode array, and the like. The exemplary aforementioned surgical variables are understood to have a significant impact on the preservation of residual hearing, full electrode insertion, and so forth.
It is another object of certain embodiments of present invention to encourage and enable the development of thinner, more flexible electrode arrays; it is understood that the thinner and more flexible the array, greater the probability of full electrode insertion, while keeping insertion forces and trauma type injuries to a minimum. Many present-day electrode arrays reserve a portion of the electrode's volume to accommodate a stylet channel configured to accommodate a stylet straightening rod or wire, necessary in the well-known AOS (Advanced Off-Stylet) method of electrode array insertion. The present invention does not require an electrode stylet channel, although it can accommodate such a feature. It is understood that electrode arrays, that do not require the reservation of space for an electrode stylet channel, will promote the design and advancement of thinner and more flexible, trauma minimizing designs.
It is yet another object of present invention to provide a removable means for straightening and stiffening an electrode array via a removable casing, initially encasing the electrode. The present invention further provides a means for the detachment of the removable casing during electrode array insertion into a cochlea. In manual electrode array insertions sans a stylet system, the use of a removable casing enclosing the electrode streamlines the array insertion process, requiring fewer push-release cycles by the surgeon.
It is further object of the present invention to include electrode array removable casings having generally tubular geometry possessing a longitudinal profile. The removable casing is fabricated from biocompatible casing material, possessing sufficient rigidity to temporarily force the electrode array into its predetermined longitudinal shape or profile.
The removable casing incorporates an integrated parting segment along its longitudinal profile. The initial function of the integrated parting segment is to substantially confine the electrode array about its outer circumference. During electrode insertion, an additional function of the integrated parting segment is to facilitate the separation or parting of the casing about its integrated parting segment eventually facilitating its complete removal during its sliding cooperation with a separator, located on a corresponding surgical tool.
It is an additional object of the present invention to provide a surgical tool for the precise control of an electrode array with respect to parameters associated with cochlea implantation. The surgical tool includes an actuation tool support arm having a tool support receiver, which can be connected to a variety of tool actuators. The actuators are preselected to control surgical variables associated with the insertion of an electrode array into cochlea so to minimize implantation trauma. Exemplary tool actuators include mechanical systems, electromechanical systems, robotic systems, manual systems, and any combination thereof, to achieve optimal results.
It is another object of the present invention to provide a surgical tool for controlling the motion of the removable casing with respect to the electrode array. A casing actuator attached to the extraction end of the removable casing provides a sliding retraction of the removable casing from the electrode array. Exemplary casing actuators include mechanical systems, electromechanical systems, robotic systems, manual systems, and any combination thereof, to achieve optimal results.
It is yet another object of present invention to provide a means for non-traumatic release of the entire electrode array system, including electrical leads, from the surgical tool. Once the removable casing is completely disconnected from the electrode array, the surgical tool completely releases the entire electrode array system in a non-traumatic manner.
It is another object of this invention to provide a relatively simple system that is economical from the viewpoint of the manufacturer and consumer, is susceptible to low manufacturing costs regarding labor and materials, and which accordingly evokes low prices for the consuming public, thereby making it economically available to the buying public.
Whereas there may be many embodiments of the present invention, each embodiment may meet one or more of the foregoing recited objects in any combination. It is not intended that each embodiment will necessarily meet each objective. Thus, having broadly outlined the more important features of the present invention in order that the detailed description thereof may be better understood, and that the present contribution to the art may be better appreciated, there are, of course, additional features of the present invention that will be described herein and will form a part of the subject matter of this specification.
In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of the components set forth in the following description or illustrated in the drawings. The present invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent construction insofar as they do not depart from the spirit and scope of the conception regarded as the present invention.
The present disclosure delineates an electrode array casing system configured to encase a cochlear electrode array as well as corresponding surgical tool for precision removal of the casing system and electrode array manipulation during cochlea implantation surgery. The overall system is configured to provide improved control over surgical variables associated with the insertion of an electrode array into a cochlea so to minimize implantation trauma, vital for the preservation of residual hearing. The electrode array casing system provides a removable means for stiffening and urging a flimsy electrode array to temporarily conform to the casing system's predetermined longitudinal profile.
Another advantage of the present invention is to provide a platform that encourages the advancement of low-trauma cochlear implantation systems, including the development of thinner, more flexible electrode arrays. There's a general understanding that the thinner and more flexible the electrode array, greater the probability of full electrode insertion, and keeping insertion forces and trauma type injuries to a minimum. Several present-day electrode arrays reserve a portion of the electrode's volume to accommodate a stylet channel configured to accommodate a stylet straightening device. The present invention does not require an electrode array possessing an electrode stylet channel, although it can accommodate such a feature. By providing a system that is capable of precision manipulation of electrode arrays, which do not possess a stylet channel, a portion of the hearing-impaired public will reap the benefits as thinner, more flexible, trauma minimizing designs are developed and enter the market.
The ensuing detailed description section makes reference to the annexed drawings. An enhanced understanding of the present invention will become evident when consideration is given to the detailed description thereof and objects other than the aforementioned become apparent. The invention will be described by reference to the specification and the annexed drawings, in which like numerals refer to like elements, and wherein:
The detachable casing for cochlear implant electrodes and deployment apparatus discussed throughout this disclosure shall have equivalent nomenclature, including, but not limited to: the device, the system, the assembly, the present invention, or the invention. Additionally, the term exemplary shall possess a single meaning throughout this disclosure; wherein the sole focus is directed to serving as an example, instance, or illustration. The terms: surgeon, or surgeons shall be broadly defined as individuals working in the field pertaining to the technology disclosed herein. The terms: front, front end, or front portion shall be understood to refer to the portion of the surgical tool or attached members that face the patient during a surgical procedure.
The term “about” is used herein to mean approximately, roughly, around, or in the region of. When the term “about” is used in conjunction with a numerical range, it modifies that range by extending the boundaries above and below the numerical values set forth. In general, the term “about” is used herein to modify a numerical value above and below the stated value by a variance of 20 percent up or down (higher or lower).
Note that as used herein and in the appended claims, the singular forms “a”, “an”, and “the” include plural reference unless the context clearly dictates otherwise. As well, the terms “a” (or “an”), “one or more” and “at least one” can be used interchangeably herein. It is also to be noted that the terms “comprising”, “including”, “characterized by”, “possessing” and “having” are all to be interpreted as open-ended terms, are all considered equivalent terms, and are used interchangeably.
With reference to the drawings of the present invention, several embodiments pertaining to the detachable casing for cochlear implant electrodes and deployment apparatus systems of the present invention thereof will be described. In describing the embodiments illustrated in the drawings, specific terminology will be used for the sake of clarity. However, the invention is not intended to be limited to the specific terms so selected, and it is to be understood that each specific term includes all technical equivalents that operate in a similar manner to accomplish a similar purpose. Terminology of similar import other than the words specifically mentioned above likewise is to be considered as being used for purposes of convenience rather than in any limiting sense.
Interface 3 is defined as the junction or contact area where the outer surface of electrode array 2 touches inner wall surface 34. Interface 3 provides a snug, yet impermanent union between the outer surface of electrode array 2 and inner wall surface 34 of removable casing 4, providing a reliable sliding relationship between the two components. Corresponding surgical tool 68 utilizes the sliding relationship by enabling a controlled retraction of removable casing 4 from electrode array 2. The retraction of removable casing 4 by surgical tool 68 is a sub-process comprising the broader process objectives, directed to the trauma-free insertion of electrode array 2 into a cochlea. In preferred embodiments, the retraction of removable casing 4 from electrode array 2 transpires in a linear fashion. Accordingly, longitudinal profile 14 is configured in a substantially linear format, as is encased portion of electrode array 2, having major axis 10. Tip 12 of electrode array 2 is shown exposed, without removable casing 4 to drive compliance to a linear format. This unconstrained portion of electrode array 2 is disposed for insertion.
Removable casing 4 includes generally open slot 6, or slit. In this embodiment, the distance between slit walls can vary, as when a slit is formed by a sharp cutting instrument. Open slot 6 is a simple type of integrated parting segment, which is incorporated into removable casing 4. The specific features or mechanisms provided by various integrated parting segment embodiments can vary, yet all are configured to split apart removable casing 4 into an open configuration 105 (
Note that for exemplary purposes, removable casings 4 are shown to possess circular cross-sectional geometries, which are configured to enclose corresponding electrode arrays 2, which have corresponding, circular cross-sectional geometries. It is understood that the cross-sectional geometries of both electrode arrays 2 and corresponding removable casings 4 can be patterned to virtually any geometric shape. In other embodiments, two different cross-sectional shapes or geometries can be used, one shape for the removable casing 4 and another for electrode array 2, and still have a situation where the removable casing 4 stiffens and constrains electrode array 2.
Outer tube support 70 is a primary support structure comprising surgical tool 68; outer tube support 70 includes a hollow internal volume which is configured to contain or accept removable casing 4 in an open configuration 105. Actuation tool support member 76 is securely attached to distal end 74 portion of outer tube support 70; tool actuation support member 76 further includes a tool support receiver attached thereon for receiving and securing a surgical tool actuator. Proximate end 72 of outer tube support 70 is concentrically attached to support end 80 of support sleeve 78. Support end 80 of support sleeve 78 additionally includes an optional expansion zone 98, approximately located where removable casing 4 enters proximate end 72 outer support tube 70 in open configuration 105 (
Mediate portion 82 of support sleeve 78 is attached to bottom end 92 portion of implant support channel 88 in a fish-mouth coupling arrangement-a fabrication configuration enabling the joining or coupling of two tubular structures such that the inner volumes of each tube are conjoined, substantially creating a new continuous tubular network. Implant support channel 88 and support sleeve 78 are obliquely connected forming an obtuse angle as depicted in
Separator 96 is a linear extension of implant support channel 88 seamlessly disposed at bottom end 92. Separator 96 device configured to gently disengage and extract removable casing 4 from cased electrode system 1 assembly, via a prying or wedging type engagement directed to interface 3, as well as immobilizing installed electrode array 2 at about inflection point 95 during removable casing 4 retraction process. Separator 96 additionally protects electrode array system from damaging pressures created by the surgical tool 68 during the implantation process.
Implant support channel 88 comprises a concaved surface 102 that has an open configuration for supporting electrode array cable 94. Concaved surface 102 is configured without restraining type obstructions, enabling unencumbered removal of electrode array cable 94 from implant support channel 88. Support sleeve 78 includes inner cylindrical segment 101 having inner diameter 103 and sleeve opening 99. In preferred embodiments sleeve opening 99 is smaller than inner diameter 103 creating a means for restraining electrode array 2 inside support sleeve 78 in situations where casing diameter 7 is larger than sleeve opening 99; in other words, when the cross-section of the U-shaped inner wall of inner cylindrical segment 101 (based on the Cartesian circular coordinate system) is over 180 degrees. In some preferred embodiments casing diameter 7 of electrode array 2 approximates inner diameter 103 such that casing outer wall surface 36 substantially engages inner surface 100, yet the engagement forces must permit a sliding relationship between casing outer wall surface 36 and inner surface 100 to enable the retraction of removable casing 4 from electrode array 2 as further depicted in
The following is an aggregate discussion highlighting fundamentals of operation with respect to the implantation system. Removable casing 4 portion of cased electrode system 1 is pulled in retraction direction 104 via retractor 120. While separator 96 immobilizes electrode array 2 at its approximate inflection point 95—which substantially corresponds to the bending point induced on electrode array 2 by implant support channel 88 and support sleeve 78 obtuse tubular configuration. Simultaneously, removable casing 4 is being forced into open configuration 105 as its being slidingly stripped off of electrode array 2, and entering expansion zone 98. As removable casing 4 is retracted, tip 12 of electrode array 2 is simultaneously ejected from removable casing 4, as depicted in
The front portion of casing holding mechanism 116 is securely attached to extraction end 114 of removable casing 4. The opposing or back end of casing holding mechanism 116 is attached to retractor 120. Lower portion of casing holding mechanism 116 is slideingly connected to stabilizing retraction bar 118—having a non-circular cross-sectional geometry, possessing anti-rotation features, to prevent twisting of removable casing 4 and the like. Retractor 120 is slideingly received via a corresponding opening located on the lower portion of stabilizing retraction bar 118. As retractor 120 is drawn in retraction direction 104, casing holding mechanism 116 and connected removable casing 4 slideingly follow in a linear manner. Accordingly, removable casing 4 is being forced into open configuration 105 as its being slidingly stripped off of electrode array 2—simultaneously tip 12 of electrode array 2 ejects from removable casing 4; thereby providing the surgeon, system or like, insertion control of electrode array 2. The figure further depicts adjustment tab 86, which is included in specific electrode array types commercially available. The present invention can accommodate such tabs, but are not required nor provide additional advantages.
In one exemplary embodiment, surgical tool actuator (e.g., system 130)—controlling surgical tool 68, in cooperation with removable casing actuator (e.g., linear system 122)—controlling the retraction rate of removable casing 4, provides a complete means for the insertion of electrode array 2 into a cochlea in accord with the aforementioned critical surgical variables. As removable casing 4 is being retracted at a predetermined rate of speed, electrode array 4 is being ejected from removable casing 4 at an identical rate of speed. In synchronization with electrode array 4 is ejection rate, surgical tool actuator (e.g., system 130) provides forward movement into a cochlea. Additionally, surgical tool actuator (e.g., system 130) will also adjust, as necessary, electrode array 4 angular considerations with respect to the cochlea to minimize cochlea trauma or injury.
The core features of manual surgical tool 133 embodiment are similar to those of embodiment surgical tool 109 shown in
Manual tool-handle 140 is securely affixed to actuation tool support member 76 and possesses substantial angular control of electrode array 2 housed inside removable casing 4 at or near skull opening 136. In one procedural embodiment a surgeon moves manual surgical tool 133 toward the skull, electrode array 2 enters the internal portion of the skull as removable casing 4 is retracted in a synchronized manner. Accordingly, the surgeon is in manual control of the insertion rate of speed associated with electrode array 2. It is understood that removable casing 4 provides most of the stiffness to cased electrode system 1 (removable casing 4 encasing comprising electrode array 2), and is configured to withstand all the manual forces exerted by the surgeon and still maintain its substantially linear geometry.
Once electrode array 2 insertion into the cochlea is complete, the surgeon retracts manual casing-handle 138 (functional equivalent of retractor 120 of
Slotted stop 134 functions as a force absorbing guide, allowing a surgeon to apply force to manual surgical tool 133 via manual tool-handle 140, resulting in the insertion of electrode array 2 into a skull (cochlea) as removable casing 4 is retracted in a synchronized manner. Accordingly, the surgeon is in manual control of the insertion rate of speed associated with electrode array 2, in addition to the angular placement of manual surgical tool 133 with respect to skull opening 137. It is understood that a substantial factor driving successful cochlear implant surgery is surgeon skill and experience.
Slotted stop 134 includes first side 146 having an engagement sleeve 150 with sleeve opening 134. Engagement sleeve 150 is configured to releasably attach to casing end 152 of removable casing 4. Other embodiments of engagement sleeve 150 can be configured to permanently attach to casing end 152. Sleeve opening 143 and slot 142 are in alignment and are both configured with sufficiently large open cavities to enable unhindered passage or release of electrode array 2 and/or electrode array cable 4, each having predetermined diameters. Slotted stop 134 includes second side 148, configured to engage skull external wall 136, and a centered opening 144 for the passage of electrode array 2 through skull opening 137 and into the cochlea.
Once electrode array 2 insertion into the cochlea is deemed complete by the surgeon, retraction of manual casing-handle 138 (functional equivalent of retractor 120 of
This utility application claims the benefit of priority from provisional application U.S. Ser. No. 63/392,227 filed on Jul. 26, 2022. Said application is incorporated by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 63392227 | Jul 2022 | US |
