This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nervous System, Subject name: Radiology
[{'content': 'CT skull giving tram track appearance is diagnostic of- \nSelect and explain. \nA. Neurofibroma, B. Tuberous sclerosis, C. Von Hippel Lindau disease, D. Sturge Weber syndrome', 'role': 'user'}, {'content': "Answer: D \nExplanation: Ans is 'd' i.e. Sturge Weber syndrome * CT scans in Sturge Weber syndrome show the tramline gyriform calcification of apposing gyri that underlies the contrast-enhancing leptomeningeal vascular malformation.Other CT scan findings Sturge Weber syndrome* Cortical atrophy* Abnormal draining veins* Enlarged choroid plexus* Blood-brain barrier breakdown (during seizures)* Contrast enhancement", 'role': 'assistant'}]