Clinical data have shown that when otoendoscopes have been used as an adjunct to ICWM or CWDM for cholesteatoma, the sinus tympani was the most common site of intraoperative residuum (cholesteatoma found with the endoscope after microscopic dissection was complete).
Therefore, for resection of cholesteatoma that extends into those areas, it is not necessary to take down the posterior canal wall if an endoscope is used as an adjunct to ICWM.
For this reason, ICWM inspection of the area near the oval window niche and posterior crus of the stapes must be thorough.
22) However, interest in closed techniques, including ICWM, has increased recently because healing time is shorter, normal anatomic structures can be maintained, and the ear's ability to self-clean is preserved.
Residual cholesteatoma rates with endoscopy-aided ICWM are comparable to those of CWDM with microscopy.
6,9) With the use of the operating microscope, each bone underwent ICWM with extension into the epitympanum, dissection of the facial recess, and removal of the posterior half of the tympanic membrane.
While some studies have shown better hearing with ICWM, others have found no significant difference in hearing between open and closed techniques.