Venous infarction of brainstem and cerebellum

The authors describe 2 cases of posterior fossa venous infarction. A 56-yea r-old woman with essential thrombocytemia presented with fluctuating compla ints of headache, nausea, vomiting, left-sided numbness-weakness, and dizzi ness and became progressively stuporous. Cranial magnetic resonance imaging (MRI) showed bilateral parasagittal frontoparietal and left cerebellar con trast-enhancing hemorrhagic lesions. On magnetic resonance venography, the left transverse and sigmoid sinuses were occluded. The second patient, a 39 -year-old woman, presented with acute onset of diplopia, numbness of the to ngue, vertigo, and right-sided weakness following a gestational age stillbi rth. MRI revealed lesions in the right half of midbrain and pons and in the superior part of the right cerebellar hemisphere. Digital subtraction angi ography showed right transverse and sigmoid sinus occlusion. The authors su ggest that one should investigate the possibility of venous infarction in t he presence of posterior fossa lesions that are often hemorrhagic and are n ot within any arterial territory distribution but respect a known venous dr ainage pattern. Recognition of the observed clinical and neuroimaging featu res can lead to earlier diagnosis and, potentially, more effective manageme nt.