Lesionectomy and tailored disconnection in a case of refractory extratemporal lobe epilepsy

A 9 year old girl presented with complaints of seizure for six years, five to six episodes per day along with a bony defect in the vertex region. Seizure was characterised by an aura of abdominal discomfort and visual hallucination. Ictal event was comprised of tonic and clonic movement of all four limbs. Post ictally there was drowsiness, vomiting and excessive salivation lasting for one hour. There was reduced visual acquity and bilateral inferior quadrantanopia. She was on four antiepileptics and on and off course of steroids. EEG was suggestive of abnormal awake and sleep multifocal IEDs and ictal seizures suggested left hemispheric involvement. Ictal EEG showed electrodecremental pattern. MRI showed a left parietal atretic cephalocoele with underlying gliosis and polygyria of left cuneus. There were many radiological abnormalities in the MRI. DTI of visual pathway showed reduced connectivity and arborisation with dysplastic left cuneus. PET CT scan showed hypometabolism of left frontal, parietal and occipital regions.

A left parietal craniotomy with excision of the herniated atretic cephalocoele along with ECoG guided lesionectomy was done. A tailored posterior disconnection was done on the basis of EcoG findings. Split calvarial graft was placed over the bony defect. Child is completely seizure free on 3 months follow up and post surgery 7th day EEG showed marked reduction in IEDS.

Histopathology revealed an encephalocoele with microdys-genesis.

Extratemporal epilepsy is commoner in children but the localisation and lateralisation is difficult in many cases due to a multitude of factors. Surgery offers reasonably good result in high refractory cases and should be done as early as possible for treating seizure, preventing cognitive decline and early social rehabilitation of child and family. A proper presurgical evaluation along with customised surgical plan is the key to a good outcome.