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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
All are true about Mastoid antrum except
assistant
The correct answer is  (B) It does not communicate with middle ear# Mastoid Antrum:> Is a large, air-containing space in the upper part of mastoid and communicates with the attic through the aditus.> Its roof is formed by the tegmen antri and is a continuation of the tegmen tympani and separates it from the middle cranial fossa.> The lateral wall of antrum is formed by a plate of bone which is on an average 1.5 cm thick in the adult.> It is marked externally on the surface of mastoid by suprameatal (MacEwen's) triangle.