This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: ENT
[{'content': 'Radical mastoidectomy includes all except: \nSelect and explain. \nA. Closure of the auditory tube, B. Ossicles removed, C. Cochlea removed, D. Exteriorisation of mastoid', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. C Cochlea removedExplanationRadical mastoidectomy is a procedure to eradicate disease from middle ear and mastoid without any attempt to reconstruct hearing.It is rarely done these days - Its only indications are:- Malignancy of middle ear- When cholesteatoma cannot be removed safely eg if it invades eustachian tube, round window or perilabrynthine cellsIf previous attempts to eradicate cholesteatoma have failedFollowing steps are done in radical mastoidectomy:Posterior meatal wall is removed and the entire area of middle ear, attic, antrum and mastoid is conveed into a single cavity, by removing the bridege and lowering the facial ridge.All remnants of tympanic membrane, ossicles (except the stapes foot plate) and mucoperiosteal lining are removed (Not cohlea)Eustachian tube is obliterated by a piece of muscle or cailageThe diseased middle ear and mastoid are permanently exteriorised for inspection and cleaning.Remember: Bridge is the most posterosuperior pa of bony meatal wall lateral to aditus and anturm, which overlies the Notch of Rivinus while facial ridge lies lateral to fallopian canal. Bridge is removed and ridge is lowered in radical or modified radical operation.', 'role': 'assistant'}]