Ictal SPECT-guided Epilepsy Surgery in a Patient with Forme Fruste Tuberous Sclerosis

Abstract

Tuberous sclerosis is an autosomal dominant disease characterised by hamartomas (tubers) in many organ systems and the four major intracranial manifestations including cortical tubers, white matter abnormalities, subependymal nodules and subependymal giant cell astrocytoma. But there is immense variability in the clinical presentation of tuberous sclerosis and many incomplete forms (formes frustes) exist. Almost all patients with tuberous sclerosis have seizures and mental retardation. The authors experienced a 7-year-old boy with medically intractable epilepsy without any skin lesion or mental retardation. In terms of surgical standpoint for determination of extent of resection, corticectomy on the overriding cortex of right premotor and lesionectomy of periventricular calcified lesion were performed according to ictal single photon emission computed tomography(SPECT), which showed hyperperfusion in the subcortical and calcified area. Histopathologic findings showed a few cytologically abnormal neurons with extensive gliosis, containing many Rosenthal fibers, reactive astrocytes and dense calcification, composing of abundant calcospherites which suggested forme fruste tuberous sclerosis. During the follow-up period of eighteen months, seizure was free after surgery.