[Spontaneous intramural intracranial artery dissection and ischemic stroke]

Spontaneous intracranial artery dissection (SIAD), leading to occlusion or stenosis of arterial lumen is a frequent but less studied cause of ischemic stroke especially in young adults. We studied 17 patients (10 men, 7 women, mean age 27.5 +/- 8.5 years) with SIAD. All the patients have undergone magnetic resonance imaging of the head, magnetic resonance angiography (MRA) (in 16 patients--follow-up MRA), 1 patient--conventional cerebral angiography. SIAD was located in the middle cerebral artery (MCA, 14 patients); posterior cerebral artery (PCA, 2 patients) and basilar artery (BA, 1 patient). Fifteen patients (88%) with SIAD developed ischemic stroke, 2 patients (12%)--a transient ischemic attack (TIA). The appearance of the local brain ischemia symptoms was combined with headache in 93% cases. The course of ischemic stroke was favorable in most cases with complete or good functional recovery in 66% of patients. A fatal outcome was observed in 1 patient (7%) with massive brain infarct. The initial cerebral angiography carried out in most cases (76%) within 3 weeks after the disease onset revealed occlusion (71%) or stenosis (29%) of corresponding cerebral arteries (MCA, PCA, BA). The last cerebral angiography conducted in 90% cases 4,5 months or later showed positive dynamics--appearance or improvement of the blood flow in these arteries--in 82% patients. The factors provoking SIAD were alcohol, contraceptive drugs and less frequent recent infection. None of patients had atherosclerosis, vasculitis or arterial hypertension. Clinical manifestations of connective tissue weakness were in 71% of patients, hypotension--65%, mitral valve prolapse--46%. In conclusion, SIAD is one of the causes of ischemic stroke and TIA in young adults and characteristic clinical manifestations and follow-up MRA have a great diagnostic importance. The development of SIAD appears to be related to weakness of connective tissue of arterial wall.