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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Most difficult site to remove cholesteatoma, i.e. sinus tympani is related with:
assistant
The correct answer is  (b) Mastoid segment of facial nerve(Ref. Cummings, 6th ed., 2193)The sinus tympani area is the hidden area of the middle ear and is the most common site of residual cholesteatoma. It lies medial to the bulge of the vertical part of fallopian canal, i.e. mastoid segment of facial nerve. It being a hidden area, it is the most difficult site to remove cholesteatoma.It can be visualised through the posterior tympanotomy approach.