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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
True about sphenoid sinus -
assistant
The correct answer is  All paranasal sinuses are lined by respiratory epithelium (i.e. ciliated pseudo stratified columnar epithilium) i.e. option a is incorrect.

Sphenoid sinus: Important points

It is not present at birth
It occupies the body of sphenoid
Ostrum of sphenoid sinus is situated in the upper part of anterior wall and drains into spheno ethmoidal recess.
On x ray: Sphenoid sinus is visible by 4 years of age.