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: Ophthalmology
[{'content': 'All are seen in CMV retinitis except \nSelect and explain. \nA. Immunosuppresion, B. Brush-fire appearance Pattern, C. Crack mud appearance, D. Perivasculitis', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Answer- C. Crack mud appearanceCMV retinitis is the most common ophthalmic manifestation of CMV.There is characteristic hemorrhagic, full thickness retinitis.Occuring as a congenital infection in infants or an oppounistic infection in the immunocompromised host.CMV retinitis is a white granular geographic lesion that clears centrally as it enlarges, leaving a quiet central area of retinal atrophy and mottled pigment epithelium. This has also been described as "brush-fire pattern.Perivascular retinitis- Frosted branch angitis with retinal perivasculitis.', 'role': 'assistant'}]