The role of neurosurgery in the management of tuberous sclerosis complex–associated epilepsy: a systematic review

Abstract

OBJECTIVE Tuberous sclerosis complex (TSC) is an autosomal dominant, multisystem neurocutaneous disorder associated with cortical tubers, brain lesions seen in nearly all patients with TSC, which are frequently epileptogenic. Seizures are often the earliest clinical manifestation of TSC, leading to epilepsy in over 70% of patients. Medical management with antiepileptic drugs constitutes early therapy, but over 50% develop medically refractory epilepsy, necessitating surgical evaluation and treatment. The objective of this study was to summarize the literature and report seizure outcomes following surgical treatment for TSC-associated epilepsy. METHODS A systematic literature review was performed in accordance with the PRISMA guidelines. The PubMed and Embase databases were searched for journal articles reporting seizure outcomes following epilepsy surgery in TSC patients. Included studies were placed into one of two groups based on the surgical technique used. Excellent and worthwhile seizure reductions were defined for each group as outcomes and extracted from each study. RESULTS A total of 46 studies were included. Forty of these studies reported seizure outcomes following any combination of resection, disconnection, and ablation on a collective 1157 patients. Excellent and worthwhile seizure reductions were achieved in 59% (683/1157) and 85% (450/528) of patients, respectively. Six of these studies reported seizure outcomes following treatment with neuromodulation. Excellent and worthwhile seizure reductions were achieved in 34% (24/70) and 76% (53/70) of patients, respectively. CONCLUSIONS Surgery effectively controls seizures in select patients with TSC-associated epilepsy, but outcomes vary. Further understanding of TSC-associated epilepsy, improving localization strategies, and emerging surgical techniques represent promising avenues for improving surgical outcomes.

Comparison of outcomes after stereoelectroencephalography and subdural grid monitoring in pediatric tuberous sclerosis complex

“…The excluded patients had a localizable epileptogenic focus on noninvasive monitoring alone and were most likely able to achieve seizure freedom with single-step resection/ablation; therefore, these outcomes were likely underreported as compared with historical studies that included only patients with TSC-associated epilepsy. 8,22,28 In this study, we noted a trend for increasing seizure freedom with longer follow-up. The study was unique because a large single center captured all patients who were observed for a significantly longer period than those included in most reported studies of TSC.…”

“…If there is clear concordance among the various noninvasive modalities regarding the location of the epileptogenic focus with correlation to a single seizure semiology, resection/ablation of the tuber may proceed without intracranial monitoring. 8,28,34,35 In cases without a dominant tuber or epileptogenic focus but with clear lateralization, unilateral intracranial monitoring is indicated. If no dominant tuber is identified and/or multiple seizure semiologies/discordant data prevail but a regional network is suggested on noninvasive workup, then bilateral intracranial monitoring may be indicated.…”

The Noninvasive Evaluation for Minimally Invasive Pediatric Epilepsy Surgery (MIPES): A Multimodal Exploration of the Localization-Based Hypothesis

“…96 Seizure reduction can result from destruction of the SOZ, network disconnection by interruption of essential pathways, or network-wide neuromodulation. [97][98][99] A map of the epileptic network can thus be a valuable addition to the presurgical evaluation. Tractography studies based on MRI diffusion tensor imaging can be used to visualize neuronal white matter tracts and provide an anatomic correlate of network paths.…”

“…96 Seizure reduction can result from destruction of the SOZ, network disconnection by interruption of essential pathways, or network-wide neuromodulation. 97 98 99…”