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': 'A young man following RTA presented with proptosis and pain in the right eye after four days. On examination, there is a bruise on the forehead and right eye. What is the diagnosis - \nSelect and explain. \nA. Cavernous sinus thrombosis, B. Internal carotid artery aneurysm, C. Carotico-cavernous fistula, D. Fracture of sphenoid', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Common causes of proptosis associated with craniofacial trauma are:-\n\n1)\xa0Carotid-cavernous fistula\nii) Retrobulbar hematoma\niii) Superior orbital fissure and orbital apex syndrome\n\nRare causes are:-\n\n\nCavernous sinus thrombosis\nSubperiosteal hematoma\n\n\nSo, amongst the given options carotico-cavernous fistula is the only common cause.\nCavernous sinus thrombosis may also occur after trauma. But, trauma is a very rare cause of CST. It usually develops as complication of extension of infection from the adjacent sinus, teeth, ear, nose etc.', 'role': 'assistant'}]