Basilar branch disease presenting with progressive pure motor stroke.

OBJECTIVE

Isolated infarcts of the pons cause well definable neurological syndromes with distinct pathomechanism, clinical course and prognosis.

RESULTS

We report 8 cases suffering from a pure motor hemiparesis that was severely progressive within the 1st 3 days and unresponsive to aspirin. A relatively good recovery was observed in all patients, however, stroke recurrence occurred in 2 cases within 3 months and resulted in pseudobulbar paralysis and tetraparesis. MRI displayed unilateral (n=6) and bilateral (n=2) ventromedial pontine infarctions (VPI). Angiographic evaluation (n=4) or color Duplex examination (n=4) revealed atherosclerotic lesions but no basilar artery occlusion.

CONCLUSIONS

Although VPI due to basilar branch disease may clinically mimic a classical lacunar syndrome, it is related to a particular pathogenetic mechanism different from microangiopathy or embolism. In contrast to the MRI feature of lacunes, VPI typically extend to the basal surface of the pons. The progressive pattern, ending up in a relative uniform clinical picture, is probably caused by propagating thrombosis.