[Secondary hematoma of the brain stem. Apropos of 5 cases].

Five cases of brain-stem hematoma are described. The cause of these hematomas was identified as "cryptic angioma" (1 cavernous angioma, 1 telangiectasia, 3 arteriovenous malformations). So, they are so-called "secondary hematoma", as opposed to brain-stem hematoma in relation with hypertension. Such secondary hematomas are reported in the literature: 37 operated on cases and 22 untreated cases were found. The clinical picture does not seem to be typical. The presentation appears to be either with the acute onset of a stroke, or with a subacute onset including relapsing symptoms. A progressive deterioration suggesting a pontine glioma or mimicking demyelination is not rare. The CT scanner appearance is often characteristic showing a high density area in the brain-stem which enhanced after injection of contrast medium with an aspect of "halo". Angiography is usually negative. The natural history of brain-stem hematoma due to rupture of a cryptic angioma is not well documented, but it seems that prognosis is very poor. So, the authors insist on surgical evacuation which is effective and safe allowing the diagnosis of brain-stem hematoma and in some cases the identification of the malformation.