Long-term follow-up of aneurysms developed during extracranial internal carotid artery dissection.

Objective: To evaluate the clinical course of aneurysms developed during extracranial internal carotid artery (ICA) dissection.
Background: Aneurysms developed during extracranial ICA dissection are detected angiographically in 5 to 40% of cervical artery dissections. The clinical and radiologic course of these aneurysms is not known, and it is not known how they should be treated.
Methods: Fifty-eight consecutive patients with extracranial ICA dissection were reviewed, and those with radiographically detectable dissecting aneurysm at the acute stage or during early follow-up were included in this study. All patients had regular clinical and MR angiography examinations. Sixteen patients (27.5%) with a total of 20 ICA dissecting aneurysms were followed for a mean period of 36.9+/-21 months (range, 10 to 93 months).
Results: No clinical symptoms suggestive of aneurysmal rupture or embolization from the aneurysm were identified. Extracranial ICA aneurysms remained unchanged in 65% of patients, were resolved in 5% of patients, and decreased in size in 30% of patients.
Conclusions: The clinical course of dissecting aneurysms was benign, although spontaneous radiologic resolution occurred rarely. Medical management with antiplatelet therapy alone (after early anticoagulation) is generally sufficient, and surgical management was seldom required.