ILAE focal cortical dysplasia type IIIc in the ictal onset zone in epileptic patients with solitary meningioangiomatosis.

"Solitary" meningioangiomatosis (MA) is a rare, benign, hamartomatous lesion of the cerebral cortex and frequently leads to epilepsy. However, the source of the epileptogenicity in meningioangiomatosis remains controversial. We report two surgically-treated meningioangiomatosis cases with medically intractable epilepsy. In both cases, chronic subdural electrocorticogram (ECoG) recordings identified the ictal onset zone on apparently normal cortex, adjacent to and/or above the meningioangiomatosis lesion, not on the meningioangiomatosis lesion itself. The ictal onset zone was resected, along with the MA lesion, and good seizure outcome was achieved. Histological examination of the ictal onset zone revealed the presence of ILAE focal cortical dysplasia (FCD) type IIIc. Our case studies suggest that in the surgical management of epilepsy with meningioangiomatosis, it is important to identify undetected, but epileptogenic, ILAE FCD Type IIIc, using preoperative multimodal examinations, including chronic ECoG recordings.

Sturge-Weber Syndrome Is Associated with Cortical Dysplasia ILAE Type IIIc and Excessive Hypertrophic Pyramidal Neurons in Brain Resections for Intractable Epilepsy.

Sturge-Weber syndrome (SWS) is a rare syndrome characterized by capillary-venous malformations involving skin and brain. Many patients with SWS also suffer from drug-resistant epilepsy. We retrospectively studied a series of six SWS patients with epilepsy and extensive neurosurgical resections. At time of surgery, the patients' age ranged from 11 to 35 years (with a mean of 20.2 years). All surgical specimens were well preserved, which allowed a systematic microscopical inspection utilizing the 2011 ILAE classification for focal cortical dysplasia (FCD). Neuropathology revealed dysmorphic-like neurons with hypertrophic cell bodies reminiscent to those described for FCD type IIa in all cases. However, gross architectural abnormalities of neocortical layering typical for FCD type IIa were missing, and we propose to classify this pattern as FCD ILAE type IIIc. In addition, our patients with earliest seizure onset also showed polymicrogyria (PMG; n = 4). The ictal onset zones were identified in all patients by subdural electrodes, and these areas always showed histopathological evidence for FCD type IIIc. Four out of five patients had favorable seizure control after surgery with a mean follow-up period of 1.7 years. We concluded from our study that FCD type IIIc and PMG are frequently associated findings in SWS. FCD type IIIc may play a major epileptogenic role in SWS and complete resection of the associated FCD should be considered a prognostic key factor to achieve seizure control.