This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: CSOM and its Complications, Subject name: ENT
Edema over the mastoid is seen in- 
Select and explain. 
A. Bell's Palsy, B. Lateral sinus thrombophlebitis, C. CSOM, D. ASOM
B: Lateral sinus thrombophlebitis
Answer: B: Lateral sinus thrombophlebitis 
Explanation: Ans. is 'b' i.e., Lateral sinus thrombophlebitis Signs of lateral sinus thrombosis (sigmoid sinus thrombosis)o Griesinger's sign:- odema over the posterior part of mastoid due to thrombosis of mastoid emissary veinso Papilloedemao Tobey-Ayer testo Crowe-Beck test:- Pressure on jugular vein of healthy side produces engorgement of retinal veins. Pressure on affected side does not produce such changeo Tenderness along jugular vein