Different Surgical Approaches for Mesial Temporal Epilepsy: Resection Extent, Seizure, and Neuropsychological Outcomes

Abstract

Background: Surgical therapy of intractable mesial temporal lobe epilepsy (MTLE) is an effective and well-established treatment. Objectives: We compared two different surgical approaches, standard microsurgical anterior temporal resection (ATL) and stereotactic radiofrequency amygdalohippocampectomy (SAHE) for MTLE, with respect to the extent of resection or destruction, clinical outcomes, and complications. Material and Methods: 75 MTLE patients were included: 41 treated by SAHE (11 right sided, 30 left sided) and 34 treated by ATL (21 right sided, 13 left sided). Results: SAHE and ATL seizure control were comparable (Engel I in 75.6 and 76.5% 2 years after surgery and 79.3 and 76.5% 5 years after procedures, respectively). The neuropsychological results of SAHE patients were better than in ATL. In SAHE patients, no memory deficit was found. Hippocampal (60.6 ± 18.7%) and amygdalar (50.3 ± 21.9%) volume reduction by SAHE was significantly lower than by ATL (86.0 ± 12.7% and 80.2 ± 20.9%, respectively). The overall rate of surgical nonsilent complications without permanent neurological deficit after ATL was 11.8%, and another 8.8% silent infarctions were found on MRI. The rate of clinically manifest complications after SAHE was 4.9%. The rate of visual field defects after SAHE was expectably less frequent than after ATL. Conclusion: Seizure control by SAHE was comparable to ATL. However, SAHE was safer with better neuropsychological results.

Tracking a changing paradigm and the modern face of epilepsy surgery: A comprehensive and critical review on the hunt for the optimal extent of resection in mesial temporal lobe epilepsy

“…Lesion volumes were substantially larger than those achieved by Parrent and Blume, and encompassed regions of the parahippocampal gyrus (48.3 ± 5.6 mm length, 20.5 ± 3.6 mm dorsoventral), but better outcomes were associated with greater percentage of the hippocampus (>50%) and amygdala (>50%) being ablated, rather than encompassing the parahippocampal gyrus (perirhinal and entorhinal cortex, 46% and 56% ablated, respectively) . Outcomes were similar to open resection (75.6% were Engel 1 at 2 years and 76.5% at 5 years following RFTC; 79.3% and 76.5% after TLR), despite hippocampal and amygdalar volume reductions being less in the former (60.6%, 50.3%) versus the latter (86.0%, 80.2%) . These reports establish that targeted ablation of the amygdala and hippocampus, if sufficient volume reductions are attained, achieve comparable seizure outcomes as compared to both open resective approaches, and suggest as well that encompassing the parahippocampal gyrus is not essential (although it was significantly ablated using this larger RFTC approach).…”

“…Although improvements have been shown in some patients in TLR series, this has not been reported at the group level, suggesting a role for preservation of lateral structures, or more judicious destruction of mesial structures. Malikova et al compared 41 patients who underwent SRFAH to 34 who had undergone ATL, using the Wechsler Adult Intelligence Scale–Revised and the Wechsler Memory Scale (WMS)‐Revised . Although this was not a randomized series, and left‐sided procedures comprised 73% of the former and only 38% of the latter, neuropsychological pre‐ and postoperative assessments showed improvement in full‐scale, verbal, and performance IQ after both left‐ and right‐sided SRFAH, with decline in full‐scale IQ or no change after ATL.…”

Automated trajectory planning for laser interstitial thermal therapy in mesial temporal lobe epilepsy

“…As fear of the operation is cited as a major factor preventing patients from undergoing surgery; a less‐invasive means of ablation may be more acceptable to patients and potentially increase surgical uptake. Thermal ablation is a lesioning technique that has been used in neurosurgery for many years with variable success . The main limitation to earlier methods was the unpredictable nature of thermal lesioning and the lack of real‐time monitoring.…”

Evaluación de la memoria en la epilepsia del lóbulo temporal para predecir sus cambios tras la cirugía. Una revisión sistemática

“…En 4 se emplean paradigmas de lenguaje, con tareas de categorización semántica (3) y de fluidez verbal (1). En el resto, se usan paradigmas de memoria, verbal (2), no verbal (2) o ambas (3). En todos ellos, la RMf permite predecir los cambios de memoria tras la cirugía, siendo el predictor más importante o añadiendo valor significativo al modelo cuando se compara con otros predictores, principalmente los test neuropsicoló-gicos y variables clínicas.…”

“…La epilepsia mesial del lóbulo temporal (ELTm) es la forma más frecuente de epilepsia focal en el adulto, siendo en muchas ocasiones refractaria al tratamiento con fármacos antiepilépticos, por lo que constituye una de las principales indicaciones de cirugía de la epilepsia, que consigue liberar al paciente de las crisis en un 60-80% de los casos [1][2][3] . Sin embargo, la intervención implica un riesgo de deterioro de la memoria, con efectos diferenciales en la memoria verbal y no verbal, en pacientes con ELTm izquierda o derecha respectivamente, siendo la memoria verbal la más vulnerable [3][4][5][6][7] .…”