Spontaneous intra-cranial arterial dissection frequently causes anterior cerebral artery infarction.

BACKGROUND AND PURPOSE: Spontaneous intra-cranial arterial dissection (SICAD) without history of head and neck injury is now recognized as an important cause of stroke. However, the frequency of SICAD involving the anterior cerebral artery (ACA), middle cerebral artery (MCA), and posterior cerebral artery (PCA) territories remains unclear. This study therefore investigated the distribution of SICAD.

METHODS

Subjects comprised 194 patients (126 men, 68 women; median age, 68.0 years) with infarct isolated to the ACA, MCA or PCA territories who underwent conventional angiography. Diagnosis of SICAD was based on clinical and neuroradiological findings. Frequency of SICAD was compared among ACA, MCA, and PCA infarcts. All patients were divided into SICAD and non-SICAD groups, and clinical characteristics were compared between groups.

RESULTS

Infarcts involved the ACA in 14 cases (7.2%), MCA in 165 cases (85.1%), and PCA in 15 cases (7.7%). SICAD was diagnosed in 17 of 194 cases (8.8%), with cerebral angiography showing main findings of the string sign in 11 patients (64.7%), the pearl and string sign in 6 patients (35.3%), and pseudoaneurysm formation in 2 patients (11.7%). SICAD most frequently involved the ACA (ACA, 64.3%; MCA, 4.2%; PCA, 6.7%; P<0.001).

CONCLUSION

SICAD was seen in 64.3% of patients with ACA infarct. The mechanisms of ACA infarction may thus differ from those of MCA and PCA infarction.