Endoscopic Assisted Posterior Tympanotomy Round Window Approach in Pediatric Cochlear Implant Surgery

By June 7, 2019

Nassif, Nader1; Zinisi, Redaelli de1; Oscar, Luca1
1 Department of Pediatric Otolaryngology – Head and Neck surgery, Brescia University Hospital, Brescia Italy

Preservation of residual hearing and vestibular function is a challenges in cochlear implantation, particularly in children. A less traumatic approach to scala tympani is established by acessing the cochlea through the round window (RW). An inadequately visible RW however; might necessitate posterior tympanotomy, a more trauamatic approach. Rigid endoscopy is an alternative method that permits the visualization of the RW niche, providing a less traumatic and invasive approach.

Children admitted for cochlear implantation through transmastoid posterior tympanotomy with inadequate visibility of RW were enrolled. A trans-posterior tympanotomy was assisted by a rigid 0° endoscope with a 1.9 mm diameter and 11 cm lenght to view of RW niche.

Between 2016 and 2018, ten children (4 males and 6 females), ages ranging from 1 to 10 years, presented for cochlear implantation with inadequate RW visibility. Endoscopy was used to provide a complete view of the RW niche, whereby the bony overhanging of the RW was drilled using a 1 mm burr until sufficient exposure was obtained. The procedure was eventually concluded using a microscope. The endoscope therefore allowed the detection and orientation plane of the basal turn, hence the corrrect angle of introduction of the multi-electrode array along the direction of the scala tympani.

Direct endoscopic view through posterior tympanotomy permits visualization of the entire RW niche, providing a soft and less traumatic approach to inner ear structures during electrode insertion.