26
Feb

Cochlear implant surgery – Robot-based electrode insertion


A 86 years old patient with a bilateral sever deafness with a loss of benefits of the hearing aids He had no cognitive impairement but a social isolation The pre-operative CT-Scan shows a procident sigmoid sinus We chose to perform a right side CI The first step is to perform a mastoidectomy The goal of the mastoidectomy is to obtain the landmarks in order to do the posterior tympanotomy You can see the procident sigmoid sinus The drilling has begun with a 7 mm cutting burr and now we use a 5 mm drilling burr Diamond burr Once we have the landmarks The incus and the LSCC We can have access to the posterior tympanotomy triangle. To begin the posterior tympanotomy you should use a 3 mm diamond burr. you should use a 3 mm diamond burr and the use 1,5 mm diamond burr We use the StimBurGard system from Medtronic in order to do this drilling and obtain continuous facial nerve monitoring. We set the stimulation of the burr at 1 mA, if we get response from the system, there is 0,3 mm of bone thickness on the FN canal The first landmark that you should identify in the middle ear, is the Stapes If you can see the Stapes head, that means that you are too forward You should see the posterior crus and the stapedian tendon. Once you have these landmarks, you should identify the promontory and then drill backward, downward and posteriorly in order to expose the RW niche. Once you have the RW niche, you should drill the RW overhang carefully with a 1 mm diamond burr The burr that we use here is covered, in order to avoid a FN trauma. Even if it is uncovered we use a low speed, in order to have a good exposure of the RW membrane. the exposure should be large This is the exposure that you should try to obtain for every CI case We use a robot the to perform the electrode array insertion The RobOtol® system from Collin The Receiver has already been placed under the skin of the patient. And now, we mount the array onto a tool which is mounted on the robot The robot is teleoperated and it will be used to insert the array within the Cochlea You can see that the array is held by the robot We now perform the RW incision with a peak or a micro-hook. You should try to do this at the very last moment, once everything is ready before the array insertion We can now proceed to CI electrode insertion In this case, we use an AB Slim J array. It’s a lateral wall (LW) array In order to have a good positionning You should place the electrode towards the Modiolus, You can see that the electrodes are facing the superior part of the surgical exposure The robot is teleoperated, we have an interface in order to drive it and place the array Here you can see that because of the perilymphe in the middle ear We have a visual impairement we suck the perilymph in the middle ear, trying not to suck directly into the cochlea we can assist the first electrode penetration the first electrode being into the cochlea we now proceed to a very slow and smooth insertion into the cochlea You can see that there is no tremor we can also observe that we can really appreciate the slow insertion, electrode by electrode You can turn around with the Microscope You can appreciate the insertion angle and the fact that every electrode is facing the Modiolus. Here you can see the blue marker at the proximal part of the array which is reaching the RW When the blue marker is reaching the RW You should stop array insertion at this point We will now secure the array with a forceps and undock the array from the robot The array is now released from the robotic arm and the robotic arm is removed from the surgical field. we now place tissue like muscle, temporal muscle fascia or fat around the array in the RW region. You should avoid any contact with the ossicular chain if you want to preserve hearing We will now secure the array with fibrin glue in order to avoid any secondary mobilization of the array in the following days we can even better secure the array with a second piece of muscle that we place in the PT this will also avoid any contact between the wires and the FN

Tags: , , , , , , , , , , , , , , , , , , , , ,

There are no comments yet

Why not be the first

Leave a Reply

Your email address will not be published. Required fields are marked *