[Sign of hyperdense and hyperintense anterior cerebral artery]

The sign of a hyperdense middle cerebral artery (MCA) in computed tomography (CT) scan, or hyperintense MCA in magnetic resonance imaging (MRI) has been associated with recent acute occlusion of the vessel. Hyperdense or hyperintense signs in the basilar and cerebral posterior arteries in association with acute infarct have also been reported. These signs may help to clarify localization and provide prognostic information, especially when the clinical findings are not clear or conclusive. We hereby report on a case of acute infarct in the anterior cerebral artery (ACA) territory with hyperdensity and hyperintensity of the affected vessel.

This is a case report of a 74 year old male patient with vascular risk factors who had the acute onset of speech impairment and left side hemiparesis, evolving over the next several hours to include depression of the level of consciousness, mutism, and right leg paresis. The A2 segment of the right ACA was found to be hyperdense in CT scan without contrast, and hyperintense in the FLAIR-MRI respectively. MR-angiography showed occlusion of the probably dominant right ACA at the A2 segment shortly after its onset.

The finding of a hyperdense and hyperintense ACA may be useful for diagnosis of acute stroke in the ACA territory, particularly in clinically ambiguous cases. To our knowledge, this is the first reported case of hyperdense and hyperintense ACA as an early sign of acute stroke. Its prognostic value in the ACA is thus far unknown.