Diaphragms of the carotid and vertebral arteries: an under-diagnosed cause of ischaemic stroke

Abstract

Background and purpose: Diaphragms of the internal carotid and vertebral arteries as a cause of ischaemic stroke are reported and stenting of diaphragms as a therapeutic option in stroke secondary prevention is described.

Methods: Five patients were cared for in our institution from 2000 to 2011 for recurrent ischaemic strokes which were classified to be of undetermined aetiology after completion of the usual investigations. Because the patients had already had ischaemic strokes in the territory of the same artery, a conventional digital subtracted angiography was performed. A diaphragm was identified on the artery that supplied the territory in which the stroke occurred. The stroke was therefore attributed to the diaphragm. Clinical and radiological data, treatment and the clinical course of the patients was retrospectively reviewed.

Results: The diaphragm was located in the vertebral artery in three cases and in the bulb of the internal carotid artery in two. In all cases cerebral MR showed ischaemic strokes of different ages downstream of the diaphragm. Stenting was performed in four cases. No patient had a symptomatic recurrent ischaemic event after stenting.

Conclusions: Diaphragms are a rare cause of recurrent embolic strokes which are often not detected with non-invasive imaging. Stenting appears to be a therapeutic option in stroke secondary prevention. These observations suggest that conventional angiography should be performed in cases of recurrent ischaemic strokes in the territory of a single artery and in cases of ischaemic stroke of undetermined aetiology in young adults when the usual investigations are negative.

Keywords: cerebrovascular disease/stroke; imaging; stroke in young adults.