[Fibromuscular dysplasia. Asymptomatic dissection and occlusion of the basilar artery].
BACKGROUND
Historically, basilar artery occlusive disease has been considered to convey a poor prognosis and a high mortality rate. In contrast, recently prospective studies have shown a better prognosis. The basilar artery is most commonly affected by atherosclerosis, but may also be affected by embolisms, dissections, aneurysms, and other conditions like fibromuscular dysplasia.


METHODS
The case of a 46 year-old male who was admitted after suffering a transient episode of ataxic gait and dysarthria is reported. Transcranial Doppler showed a stenotic flow in the basilar artery with distal embolic signals. Magnetic resonance (MR) angiography demonstrated an isolated fibromuscular dysplasia of the basilar artery that caused a > 50% stenosis without parenchymal lesions. Oral anticoagulation treatment was initiated. The control MR angiography performed ten months later, and although the patient was asymptomatic, showed a dissection which evolved into a complete occlusion of the basilar artery. Its distal portion was filled via a reverse flow from both posterior communicating arteries. Anticoagulation treatment was discontinued.


CONCLUSIONS
Fibromuscular dysplasia of the basilar artery is a rare and usually asymptomatic disease. It may develop into a dissection, but the usual clinical presentation is stenosis-related ischemic stroke. Intracranial artery dissections may be further complicated by subarachnoid hemorrhage. Many authors have recommended anticoagulant therapy for fibromuscular dysplasia. Basilar artery occlusion, as this case shows, does not always convey a poor prognosis. This is determined, at least partially, by the presence of good collateral circulation.
Benavente
L
L
Servicio de Neurología, Hospital Universitario Central de Asturias, Oviedo. lbf_benfer@hotmail.com
Calleja
S
S
Fernández
J M
JM
Lahoz
C H
CH
D000784:Aortic Dissection / Q000209:etiology / Q000473:pathology; D001488:Basilar Artery / Q000473:pathology*; D003251:Constriction, Pathologic; D003937:Diagnosis, Differential; D005352:Fibromuscular Dysplasia / Q000150:complications / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis