Clinical features and prognosis in young adults with infratentorial infarcts

Background and Purpose: Many comprehensive descriptions of the clinical spe ctrum of infratentorial infarcts in elderly patients and with a retrospecti ve design have been published. The aim of this study was to describe the cl inical characteristics and prognosis in young patients with isolated infrat entorial infarcts. Methods: In a prospective series of 105 patients aged 18 -44 years with cerebral infarction 24 had a brainstem or cerebellar infarct ion. The patient selection was validated in a population-based epidemiologi cal survey. The patients were assessed acutely and at 4 and 12 months after onset. Extensive evaluation included CT and MRI scans, angiography, ultras onic duplex scanning, transesophageal echocardiography and a chemistry pane l including hematologic testing. The modified Rankin scale and NIH stroke s cale were used for assessment of disability and neurological dysfunction. R esults: Eighteen patients had a cerebellar infarct (posterior inferior cere bellar artery territory in 9 patients, superior cerebellar artery in 6, ant erior inferior cerebellar artery in 2, nonterritorial in 1). Two patients h ad lateral medullary infarcts and 2 isolated pontine infarcts. In 2 patient s MRI was normal despite repeated investigations. Hearing loss and tinnitus were the only explicit symptoms for superior cerebellar artery infarcts, b ut it was otherwise impossible to classify each case to a vascular territor y according to clinical characteristics. The age-specific incidence of isol ated cerebellar infarction was 1.8/100,000/year. The presumed causes were a rterial dissection in 8 patients, idiopathic in 7, cardioembolic in 5, oral contraceptive use in 3 and protein S deficiency in 1 patient. One patient died during the acute phase and another developed a locked-in syndrome. At follow-up, 1 patient had a transitory ischemic attack and 1 a silent cerebr al infarction. Twenty two patients had a favorable outcome according to the modified Rankin scale (grade 0-2) and the NIH scale. Conclusions: Cerebell ar infarctions are frequent among young stroke patients in northern Sweden. Arterial dissection is the prevailing stroke mechanism in infratentorial i nfarcts. The prognosis is favorable regarding motor impairment but cognitiv e deficits may prevent return to work.