Robot-Assisted Transcanal Endoscopic Ear Surgery for Congenital Cholesteatoma

This protocol is significant as it shows the feasibility of a two-handed endoscopic technique in the narrow auditory canal of a three-year-old child for congenital cholesteatoma removal. The congenital cholesteatoma can be seen in the middle ear cavity. Although there's no bony erosion, it extends from the ossicles to the supratubal recess.

After inserting the endoscope into the holder, carefully examine the tympanic membrane of the patient. Infiltrate the ear canal to prevent the accumulation of coagulated blood. Using an angled cautery needle set to low power, open the tympanic cavity inferiorly, posteriorly, and superiorly along the chorda tympani, until the malleus neck is identified.

Then elevate the tympanum from the manubrium, and push the tympanomeatal flap anteriorly. Using a hook or needle, separate the congenital cholesteatoma from the incus and stapes, and push it anteriorly under the malleus with a Fisch microdissector. Now, open the congenital cholesteatoma matrix in the controllable posterior-inferior portion and use a large suction to debulk it.

Dissect the congenital cholesteatoma from the promontory and malleus, and remove it. Using an angled endoscope, inspect the tympanic cavity. Reinforce the tympanic membrane and insert cartilage in an underlay position to prevent subsequent retraction pockets.

Replace the tympanomeatal flap on the body canal and pack it with absorbable foam, starting with the anterior part of the tympanum to avoid any subsequent lateralization. Preoperative audiometry revealed a 10-decibel conductive hearing loss in the left ear, causing a minor asymmetry with the normal hearing in the right ear. Six weeks post-operation, 10-decibel conductive hearing loss was observed in the left ear, but notably, there was no sensorineural hearing loss.

This robotic technique paves the way for future research to synchronize the robotic arm with 3D mapping on the CT scan and develop augmented reality.