This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Ear, Subject name: ENT
Ca Wheel sign is seen in 
Select and explain. 
A. ASOM, B. AOM, C. OME, D. CSOM
A: ASOM
Answer: A: ASOM 
Explanation: In a stage of pre-suppuration of ASOM, there is congestion of pars tensa. A leash of blood vessels appears along with the handle of malleus and at the periphery of tympanic membrane impaing it a ca-wheel appearance. Later, whole tympanic membrane including pars flaccid becomes uniformly red. Ref: Textbook of diseases of ENT, PL Dhingra, 7th edition, pg no. 67