Long-term surgical outcomes in patients with drug-resistant temporal lobe epilepsy and no histological abnormalities

Prognostic factors for seizure outcome in patients with MRI-negative temporal lobe epilepsy: A meta-analysis and systematic review

“…MRI-negative TLE is considered one of the main factors that predicts poor seizure outcome due to the technical difficulties involved in localizing and resecting the entire epileptogenic focus [2,3,8]. Therefore, we aimed to determine which prognostic factors could effectively predict favorable seizure control after surgery in the setting of normal brain MRI results.…”

“…Patient selection bias toward MRI-negative TLE is more likely in hospital-based samples. Several studies only included patients with MRI-negative mesial TLE [19], TLE patients exhibiting MRI-negative and PET positive results [14], patients without any histological abnormalities [8] or patients with MRI-negative neocortical TLE [17]. Moreover, the varied diagnostic test battery applied in different studies may have an impact on the precision to delineate the epileptogenic zone and hence influenced seizure outcome.…”

“…The rate of postoperative seizure freedom among patients with MRI-negative TLE reported in previous studies was varied, ranging from 16% to 56.4% [2][3][4][5][6][7][8][9]. This variable seizure-free rate after surgery was largely due to the small numbers of patients and differences in the recruitment criteria, preoperative evaluations, surgical approaches, and follow-up duration.…”

“…Several studies have attempted to identify the prognostic factors for seizure-free outcome after surgery in MRI-negative TLE patients, including age, epilepsy duration, pathology, and fluorodeoxyglucose positron emission tomography (FDG-PET), single photon emission computer tomography (SPECT), scalp electroencephalogram (EEG), and intraoperative EEG results [2,5,[7][8][9][11][12][13][14][15][16][17][18][19][20][21][22][23]. However, further investigation is required due to the shortage of cases and the inconsistent and occasionally contradictory findings.…”

Outcome of Epilepsy Surgery in MRI-Negative Patients Without Histopathologic Abnormalities in the Resected Tissue

“…Alternatively, especially in the absence of an MRI-visible lesion, histopathology may be normal because the epilepsy is truly nonlesional and caused by mechanisms that cannot be detected with microscopic testing, such as genetic etiologies causing focal epilepsy. 9 , 10 …”