1 Department fo Otolaryngology, Eye Ear Nose & Throat Hospital of Fudan University, Shanghai China.
When cholesteatoma extends into the whole mastoid cavity, endoscopic tympanoplasty should combine mastoidectomy.
All the patients have the cholesteatoma extending into the mastoid. We used two endoscopic approaches to conduct the mastoidectomy. The first one is transcanal approach, a big tympanomeatal flap should be made, and the lateral skin incision is about 1.2-1.5 cm away from the tympanic ring , so the posterior canal bone wall could be exposed widely. We used the diving drill technique to remove the posterior canal wall bone, exposing the cholesteatoma in the deep mastoid by 70° or 90 ° endoscope. After the complete removal of cholesteatoma, the tragus cartilage is used to reconstruct the posterior wall of external auditory canal (EAC). The second method is transcanal approach combining with the traditional endoaural approach. We made an incision between the canal and the helix to explore the ethmoid region of the mastoid, and then drilled the bone of the lateral wall of the antrum, exploring the cavity of the mastoid.
Results: The diving drill could be conduct clearly. The drilling work was usually no more than 15 minutes. The assistant could hold the endoscope or the suction tube in endoscopic mastoidectomy, the surgeon would feel similarly as two hands operation. Endoscopic mastoidectomy could be applied even in the presence of the dehiscence of the lateral semicircular canal and mastoid tegmen. The cutting bone work is much less than under the microscope, so the total operation time is similar with the microscope operation.
The cholesteatoma extending into the mastoid is indication for endoscopic surgery.