A 68-year-old man on long-term warfarin presents with three weeks of fluctuating headaches and episodic drowsiness following a trivial slip in the bathroom. CT brain shows a hypodense crescentic collection over the left convexity that crosses suture lines and displaces cortex without involving the sulci. The most likely diagnosis is:

• A Subarachnoid haemorrhage
• B Extradural haematoma
• C Chronic subdural haematoma ✓
• D Cerebral contusion

Explanation

Chronic subdural haematoma follows tearing of bridging cortical veins, typically in elderly patients after minor trauma, and anticoagulation is a strong risk factor. On CT it appears as a crescentic or concavo-convex collection that freely crosses suture lines and follows the convexity of the brain. An extradural haematoma is biconvex or lens shaped and is limited by sutures because the dura is attached there. Its source is usually middle meningeal arterial bleeding, giving a different tempo and shape.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.