Related Experiment Video
Updated: May 11, 2026
Anteromesial Temporal Lobectomy for Medically Intractable Temporal Lobe Epilepsy: An Operative Study
Published on: August 15, 2025
Seizure outcome in surgically treated drug-resistant mesial temporal lobe epilepsy based on the recent
Marco Giulioni1, Gianluca Marucci, Matteo Martinoni
1Division of Neurosurgery, IRCCS Institute of Neurological Sciences, Bellaria Hospital, Bologna, Italy. giulioni.m@tiscali.it
Object:
The study was performed to investigate the relation between seizure outcome after surgical treatment of mesial temporal lobe epilepsy (MTLE) and pathological findings, classified according to the recently proposed classifications of mesial temporal sclerosis (MTS), granule cell pathology (GCP), focal cortical dysplasia (FCD) and epilepsy-associated low-grade tumors (ELGT).
Methods:
The authors analyzed data obtained in 120 consecutive cases involving patients presenting with drug-resistant MTLE, who underwent tailored anteromesial temporal lobe resection, and correlated seizure outcome with pathological findings. They identified 5 histopathological groups: Group 1-ELGT, alone or associated with other lesions (30 cases); Group 2-isolated FCD (17 cases); Group 3-MTS, with or without GCP (28 cases); Group 4-MTS associated with FCD, with or without GCP (37 cases); Group 5-other lesions (8 cases).
Results:
Engel Class I outcome was observed in 83% of patients with ELGT (Class IA in 63%); in 59% of patients with isolated FCD, with FCD Type II showing a better prognosis than FCD Type I; in 82% of patients with isolated MTS (Class IA in 50%), with MTS Type 1a and MTS Type 1b showing a better prognosis than MTS Type 2 and patients with MTS and GCP having better postsurgical results than those with MTS without GCP. Engel Class I outcome was also achieved in 84% of patients with FCD associated with MTS (Engel Class IA in 62%); also in this group MTS 1a and MTS 1b associated with FCD showed a better prognosis than FCD associated with MTS 2. Finally, Engel Class I was also achieved in 2 patients with vascular malformation and in 1 with a temporal pole encephalocele.
Conclusions:
Patients with MTLE and ELGT, MTS, or MTS associated with FCD showed the best postsurgical seizure outcome (Engel Class I in more than 80% of cases), whereas only 63% of patients with isolated FCD achieved the same type of outcome. Interestingly, the analysis of seizure outcome in histopathological subtypes of FCD and of MTS showed different prognoses in the different pathological subgroups, with worse outcomes for atypical MTS, absence of GCP, and isolated FCD Type I.
Insights
Patients with mesial temporal lobe epilepsy (MTLE) and epilepsy-associated low-grade tumors (ELGT), mesial temporal sclerosis (MTS), or MTS with focal cortical dysplasia (FCD) have excellent seizure outcomes after surgery. Isolated FCD showed a lower success rate, with specific subtypes impacting prognosis.
Area of Science:
- Neurology
- Neurosurgery
- Pathology
Background:
- Mesial temporal lobe epilepsy (MTLE) is a common cause of drug-resistant epilepsy.
- Surgical treatment offers a potential cure, but outcomes vary based on underlying pathology.
- Accurate histopathological classification is crucial for predicting surgical success.
Purpose of the Study:
- To investigate the relationship between surgical seizure outcome and histopathological findings in drug-resistant MTLE.
- To evaluate the prognostic value of recently proposed classifications for mesial temporal sclerosis (MTS), granule cell pathology (GCP), focal cortical dysplasia (FCD), and epilepsy-associated low-grade tumors (ELGT).
Main Methods:
- Analysis of 120 consecutive drug-resistant MTLE cases undergoing anteromesial temporal lobe resection.
- Correlation of seizure outcome (Engel Class) with 5 identified histopathological groups: ELGT, isolated FCD, MTS (with/without GCP), MTS associated with FCD, and other lesions.
- Detailed examination of prognostic differences within subtypes of FCD and MTS.
Main Results:
- Excellent Engel Class I seizure outcome (>80%) was achieved in patients with ELGT, MTS, or MTS associated with FCD.
- Isolated FCD cases had a lower Engel Class I outcome rate (59%), with FCD Type II performing better than FCD Type I.
- Specific MTS subtypes (1a, 1b) and the presence of GCP were associated with better outcomes compared to atypical MTS or isolated FCD Type I.
Conclusions:
- Histopathological findings significantly influence postsurgical seizure outcomes in MTLE.
- ELGT, MTS, and MTS with FCD represent favorable prognostic groups.
- Subtype analysis of FCD and MTS reveals distinct prognoses, highlighting the importance of detailed pathological assessment for personalized treatment strategies.
Related Concept Videos
01:24Epilepsy and Seizures: Overview
Various factors can trigger epilepsy, including genetic factors, brain damage, metabolic causes, and unknown etiology. Diagnosis of epilepsy involves electroencephalography (EEG), which...
01:22Epilepsy ll: Types
01:13Seizures: Classification
Seizures are typically classified into two main categories: focal and generalized seizures.
Focal Seizures
Focal seizures originate from specific regions of the brain. These seizures are further sub-classified into two types:
01:20Seizures l: Introduction