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': 'Schwartz operation is also called as - \nSelect and explain. \nA. Cortical mastoidectomy, B. Modified radical mastoidectomy, C. Radical mastoidectomy, D. Fenestration operation', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Mastoidectomy is defined as a surgical procedure which opens up the mastoid cavity, cleans up the infected air cells, improves middle ear ventilation by widening of the aditus.\nThere are several types of mastoidectomy.\n\nCortical mastoidectomy (simple mastoidectomy or schwartz operation)\n\nThe mastoid air-cell system is exenterated, including epitympanum.\nBut the posterior meatal wall (canal wall) is left intact.', 'role': 'assistant'}]