Pathology and Neuroimaging in Pediatric Temporal Lobectomy for Intractable Epilepsy

Abstract

Objectives: Firstly, to study the pathology at surgery in children undergoing temporal lobectomy for intractable partial epilepsy. Secondly, to compare neuroimaging techniques (CT, MRI) in the preoperative detection of pathology. Lastly, to examine the surgical outcome in children. Methods: Forty-two pediatric patients undergoing temporal lobectomy for intractable epilepsy at the Comprehensive Epilepsy Program at the University of Alberta Hospital between the years 1988–1998 were studied. Patients had extensive preoperative investigations including CT and MRI. The pathology at surgery was reviewed and compared to preoperative neuroimaging. Charts were reviewed to determine surgical outcome. Results: Brain tumors were the most common pathology, found in 13/42 patients. Mesial temporal sclerosis (MTS) was found in 8 patients and dual pathology in an additional 5. Focal cortical dysplasia (FCD) was seen in 4 patients, 1 patient had a porencephalic cyst and 4 patients had tubers of tuberous sclerosis. Seven patients had no specific pathology detected. MRI was clearly more sensitive than CT in the detection of pathology. MRI was abnormal in 27/42 cases (64%), while CT scan was found to be abnormal in only 12/39 (31%). Surgical outcome was excellent, with 34/42 patients (80%) having an Engel class I outcome. One patient had significant improvement with an Engel class II outcome, 3 (7%) had little improvement (Engel class III) and 4 (10%) were unchanged (Engel class IV). Three patients (7%) had surgical complications. Conclusions: A wide variety of developmental pathology is seen following temporal lobectomy for intractable epilepsy of childhood. Brain tumors, FCD and MTS are common. MRI is superior to CT in the detection of pathology, which may be subtle in children. Surgical outcome is excellent, with most children being seizure free and few complications being seen.

Apnea Caused by Mesial Temporal Lobe Mass Lesions in Infants: Report of 3 Cases

“…Rasmussen found that approximately 25% of patients undergoing epilepsy operation and having a tumor were younger than 15 years old. 16 Most recently, Sinclair et al 17 (31%) aged younger than 16 years. Studies describing the pathology in infants with intractable epilepsy are limited.…”

Seizure outcome of lesionectomy in glioneuronal tumors associated with epilepsy in children

“…Some investigators consider complete tumor excision sufficient, 21,24,29,37,42,49,52 whereas others advocate the identification and resection of epileptogenic zones as necessary to provide a good seizure outcome. 2,22,25,27,33,38,41,43,50,57 Without a proper understanding of the controversial pathophysiological mechanisms leading to tumoral epilepsy, however, it will be difficult to determine the optimal surgical strategy.…”

“…3,5,50,56 In the study by Clusman and coworkers 11 all of the children who underwent only lateral temporal lesionectomies became seizure free. Few studies, however, have specifically focused on the long-term seizure outcome after lesionectomy in selected series of children harboring glioneuronal tumors.…”

Brain tumor epilepsy: A reappraisal and six remaining issues to be debated

“…Another report mentioned 14% of tumoral etiologies among adults with mesial temporal lobe epilepsy (Soeder, Gleissner et al 2009). Brain tumors could even be more frequent in children with temporal lobe epilepsy, as suggested by surgical case series (Sinclair, Wheatley et al 2001). However, seizure are uncommon as a revealing mode of brain tumors in children, accounting for only 10,2% of a case series, where over symptoms appeared to predate epilepsy (Ibrahim and Appleton 2004).…”