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': 'Dalen fuchs nodules ? \nSelect and explain. \nA. Sympathetic Ophthalmitis, B. Chronic iridocyclitis, C. Neurofibromatosis, D. Trachoma', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Sympathetic Ophthalmitis Dalen fuch's nodules are seen in sympathetic ophthalmitis. Dalen-Fuchs' nodules are formed due to proliferation of the pigment epithelium (of the iris, ciliary body and choroid) associated with invasion by the lymphocytes and epitheloid cells. Retina shows perivascular cellular infiltration (sympathetic perivasculitis).", 'role': 'assistant'}]