This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Traumatic Brain Injury, Subject name: Surgery
After head injury, biconvex, lenticular shape hematoma in CT scan is characteristic of which of the following : 
Select and explain. 
A. Extradural haemorrhage, B. Subdural haemorrhage, C. Intracerebral hematoma, D. Diffuse-axonal injury
A: Extradural haemorrhage
Answer: A: Extradural haemorrhage 
Explanation: Ans ie 'a' ie Extradural haemorrhage (Ref. : Chapman, 3/e, p438)CT scan (non-contrast) is the best diagnostic method to evaluate a head injury pt. (better than MRI)On CT scan -Extradural haemorrhage appears as biconvex lentiform opacity. *Subdural haemorrhage appears as concavoconvex crescentic opacity. *Intracerebral blood appears on small foci, typically at grey/white matter interface, or more centrally in the white matter.