Clinical features and prognosis in young adults with infratentorial infarcts

Many comprehensive descriptions of the clinical spectrum of infratentorial infarcts in elderly patients and with a retrospective design have been published. The aim of this study was to describe the clinical characteristics and prognosis in young patients with isolated infratentorial infarcts.

In a prospective series of 105 patients aged 18-44 years with cerebral infarction 24 had a brainstem or cerebellar infarction. The patient selection was validated in a population-based epidemiological survey. The patients were assessed acutely and at 4 and 12 months after onset. Extensive evaluation included CT and MRI scans, angiography, ultrasonic duplex scanning, transesophageal echocardiography and a chemistry panel including hematologic testing. The modified Rankin scale and NIH stroke scale were used for assessment of disability and neurological dysfunction.

Eighteen patients had a cerebellar infarct (posterior inferior cerebellar artery territory in 9 patients, superior cerebellar artery in 6, anterior inferior cerebellar artery in 2, nonterritorial in 1). Two patients had lateral medullary infarcts and 2 isolated pontine infarcts. In 2 patients MRI was normal despite repeated investigations. Hearing loss and tinnitus were the only explicit symptoms for superior cerebellar artery infarcts, but it was otherwise impossible to classify each case to a vascular territory according to clinical characteristics. The age-specific incidence of isolated cerebellar infarction was 1.8/100,000/year. The presumed causes were arterial 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 cerebral infarction. Twenty-two patients had a favorable outcome according to the modified Rankin scale (grade 0-2) and the NIH scale.

Cerebellar infarctions are frequent among young stroke patients in northern Sweden. Arterial dissection is the prevailing stroke mechanism in infratentorial infarcts. The prognosis is favorable regarding motor impairment but cognitive deficits may prevent return to work.