Sturge-Weber syndrome associated with arteriovenous malformation in a patient presenting with progressive brain edema and cyst formation.

Sturge-Weber syndrome (SWS) is a neurocutaneous disorder presenting with a facial port-wine stain, along with an occipital leptomeningeal angiomatosis that is typically located ipsilateral to the stain. In this paper, the authors present a rare case of SWS associated with an arteriovenous malformation (AVM) instead of an angiomatosis in the ipsilateral occipital lobe. While the patient was in the care of the authors, the AVM progressively enlarged, and was accompanied by progressive stenoocclusive changes of the venous system. The resulting brain edema finally brought about a serious neurological condition 13 years after the initial diagnosis. Transarterial embolization and medical treatments decreased the edema. Subsequently, however, a large intraparenchymal cyst appeared, aggravating the patient's motor weakness. Aspiration of the cyst ameliorated these symptoms. The analysis of the fluid from the cyst revealed that it contained a very high concentration of protein. Although there is no proven pathogenic mechanism to explain these protein concentrations and the enlargement of the AVM, the authors hypothesize that the progressive edema resulted from a synergic augmentation of the inflow from the AVM and the progressive obstruction of venous drainage that is a hallmark of SWS. The formation of the cyst probably resulted from the blood vessel hyperpermeability that is inherent to SWS.