Background and Purpose—We set out to investigate the predictors and time course for recanalization of spontaneous dissection of the cervical internal carotid artery (SICAD).

Methods—We prospectively included 249 consecutive patients (mean age, 45±11 years) with 268 SICAD. Ultrasound examinations were performed at presentation, during the first month, and then at 3, 6, and 12 months, and clinical follow-ups after 3, 6, and 12 months.

Results—Of 268 SICADs, 20 (7.5%) presented with 50% stenosis, 31 (11.6%) with 51% to 80% stenosis, 92 (34.3%) with 81% to 99% stenosis, and 125 (46.6%) with an occlusion. Antithrombotic treatment included anticoagulation in 174 (67%) patients, aspirin in 64 (24%) patients, and aspirin followed by anticoagulation or vice versa in 22 (8%) patients. Follow-up ultrasound showed normal findings in 160 (60%), 50% stenosis in 27 (10%), 51% to 80% stenosis in 4 (1%), 81% to 99% stenosis in 26 (10%), and occlusion in 51 (19%) vessels. The rate of complete recanalization was 16% at 1 month, 50% at 3 months, and 60% at 6 and 12 months. Initial occlusion of the dissected vessels reduced the odds of recanalization (OR, 4.0; 95% CI, 2.2–7.3; P<0.001), whereas the occurrence of local symptoms and signs only at presentation were independently associated with complete recanalization (OR, 0.4; 95% CI, 0.2–0.8; P=0.048).

Conclusions—These results suggest that recanalization of SICAD occurs mainly within the first 6 months after the onset of symptoms. Initial occlusion reduces the likelihood of complete recanalization, whereas presentation with local symptoms and signs only increases it.