Sturge-Weber (SW) syndrome or encephalotrigeminal angiomatosis is caused by a leptomeningeal hemangioma that leads to progressive unilateral brain ischemia and subsequent atrophy.
As in this case, SW characteristically presents with an ipsilateral facial port-wine stain at the V1 trigeminal nerve distribution in a child with seizures. The diagnosis was achieved with those clinical and imaging features.