Middle Cerebral Infarct Secondary to Carotid Artery Dissection

Clinical History

A 17 year old, previously well, male presented with acute onset of confusion and right sided weakness. The only previous medical history was of recreational drug use.

The patient underwent cranial imaging with CT and MR.

Imaging Findings

A 17 year old male disc jockey presented to the Accident & Emergency department with a 12 hour history of an acute confusional state and a 6 hour history of right sided weakness. He had been found in a hotel room by friends. Prior to this episode the patient was fit and well with no previous medical history. He admitted to regular use of recreational drugs.

On clinical examination the patient was acutely confused with a GCS of 14/15 and had a right sided hemiplegia.

The patient proceeded to CT of the brain which showed early changes within the left cerebral hemisphere of subtle loss of grey-white matter differentiation (Figure 1) in the territory of the left middle cerebral artery (MCA) and poor definition of the left basal ganglia. The left MCA was hyper-dense (Figure 2). The appearances were in keeping with an acute infarct within the territory of the left MCA. This was further confirmed by MRI (Figure 3), showing abnormal diffusion weighted imaging (DWI) consistent with a left MCA infarction, likely from dissection of the left internal carotid artery (not shown). The patient went on to have CT angiography of the neck and Circle of Willis which confirmed a tapered narrowing of the left internal carotid artery in keeping with dissection (Figure 4). A toxicology screen was positive for mixed amphetamines including “Ecstasy” and other stimulants. All other laboratory tests were normal.

Discussion

Carotid artery dissection is an uncommon cause for ischaemic stroke, accounting for approximately 2% of all strokes. However, when this occurs in the young adults and children it accounts for approximately 20%. Ischaemic neurological findings occur in 30-80% of cases of dissections. In 20% of cases (like ours) a complete stroke may develop.

In this case there were none of the more common risk factors for carotid dissection such as trauma, neck manipulation (chiropractice), hypertension or fibromuscular dysplasia. Our patient did use recreational drugs, including metamphetamine, which is suspected to be associated with carotid dissection. Cocaine has also be implicated in carotid artery dissection. The mechanism of injury proposed includes vasospasm, hypertension and direct vascular injury.

Differential Diagnosis List

Final Diagnosis

Middle Cerebral Infarct Secondary to Carotid Artery Dissection

URL:	https://www.eurorad.org/case/6855
DOI:	10.1594/EURORAD/CASE.6855
ISSN:	1563-4086