A CT of the head performed immediately after a road traffic accident shows a hyperdense biconvex extra-axial collection with a lucid interval history. The collection crosses the midline but is limited by a suture. What is the most likely diagnosis?

• A Acute subdural haematoma
• B Subarachnoid haemorrhage
• C Intracerebral contusion
• D Epidural haematoma ✓

Explanation

Epidural haematoma appears as a hyperdense biconvex (lenticular) collection on CT, classically does not cross sutures (because the dural attachments at sutures prevent extension), and the patient may have a lucid interval. Middle meningeal artery tear is the usual cause. Acute subdural haematoma is crescent-shaped and can cross sutures. SAH fills cisterns and fissures. Contusions appear as heterogeneous parenchymal lesions.

Reference: Grainger & Allison's Diagnostic Radiology, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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