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: Anatomy
Korner's septum is seen in ? 
Select and explain. 
A. Petrosquamous suture, B. Temporosquamous suture, C. Petromastoid suture, D. Frontozygomatic suture
A: Petrosquamous suture
Answer: A: Petrosquamous suture 
Explanation: Mastoid develops from squamous and petrous bone.Korner's septum is persistence of petrosquamous suture in the form of a bony plate.Korner's septum is surgically impoant as it may cause difficulty in locating the antrum and the deeper (ells, and thus lead to incomplete removal of disease at mastoidectomy. Mastoid antrum cannot be reached unless theKorners septum has been removed.