Acute CT Brain
Acute ischaemia

In the setting of acute stroke the initial CT is often normal; the main purpose of performing a CT is to exclude intracranial haemorrhage.

Signs of acute stroke

Occasionally a CT brain acquired shortly after an acute vascular event will show subtle low density in the territorial area affected. Other important signs include the 'hyperdense artery' sign and the 'insular ribbon' sign. These signs are easily overlooked if not checked for routinely.

Hyperdense artery sign

In the setting of an acute infarct, CT occasionally shows thromboembolic material within a cerebral artery, most commonly the middle cerebral artery.

Insular ribbon sign

In the context of an acute infarct, CT may demonstrate loss of clarity of the insular ribbon. This is a very subtle finding and so is easily overlooked unless checked for routinely.