Spontaneous right ICA dissection - underlying bilateral fibromuscular dysplasia

Case contributed by Dr Chris O'Donnell


Right sided neck pain for days, now nausea, vomiting and unsteady gait.

Patient Data

Age: 35
Gender: Female

CT brain was normal. CT angiogram performed to investigate possible dissection.

Luminal irregularity with slight overall dilatation of distal internal carotid arteries. On the right there is associated Localized intimal dissection (arrow) with pseudodivericulum formation best seen on the sagittal reconstruction.

Case Discussion

Fibromuscular dysplasia (FMD) is an arterial disease of unknown etiology typically affecting the medium and large arteries of young to middle-aged women.

There are 3 types of FMD: intimal, medial, and subadventitial (perimedial) but this is not easily differentiated on CT/angiography.  It is often asymptomatic but can be associated with spontaneous dissection.

3 CT/angiographic findings:

Type 1

This is the most common form. Angiography reveals the typical "string-of-beads" appearance, with alternating segments of stricture and dilation. This type is usually a result of medial fibroplasia of the arterial wall.

Type 2

Less commonly a long tubular stenosis may be seen. This is associated with any of the histologic types, but it is most commonly seen with the intimal form.

Type 3

This unusual form is characterized by involvement of only 1 side of an artery. May lead to saccular aneurysms and can be difficult to distinguish from atherosclerotic ulceration and pseudoaneurysm.

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Case information

rID: 29603
Published: 8th Jun 2014
Last edited: 16th Jul 2018
System: Vascular
Inclusion in quiz mode: Included

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