Three-dimensional preoperative maps of hippocampal atrophy predict surgical outcomes in temporal lobe epilepsy

Abstract

The authors used surface-based anatomic mapping to detect features of hippocampal anatomy that correlated with surgical outcomes in patients undergoing surgery for mesial temporal lobe epilepsy with hippocampal sclerosis. Compared with a seizure-free group, hippocampal profiles for the non-seizure-free group had greater diffuse ipsilateral atrophy and more region-specific contralateral atrophy in the anterior, lateral hippocampus. These atrophic regions may indicate areas of increased epileptogenicity, contributing to poorer surgical outcomes.

A meta-analysis on progressive atrophy in intractable temporal lobe epilepsy

“…41 This caveat appears particularly relevant for cross-sectional studies. In 18 of the latter (47.4%), 14,16,[20][21][22]24,30,[33][34][35][36][37][38]40,42,[50][51][52] no statistical approaches were implemented to correct for the effects of age. Although the remaining studies addressed aging, no consistent method was chosen: 3 reported no significant effects of age on morphometric measures in controls, 15,32,48 3 found no effect of age or no effect of age at epilepsy onset in patients, 19,29,53 2 corrected for age at onset, 18,28 5 corrected for age in patients, 17,26,47,49,54 4 utilized MRI measures adjusted for age 13,31,39,46 (based on regression models derived from controls), 1 calculated epilepsy duration/age ratios, 23 2 statistically compared chronological age effects between patients and controls.…”

Volumetric and shape analysis of hippocampal subfields in unilateral mesial temporal lobe epilepsy with hippocampal atrophy

“…Hippocampal shape analysis can provide information regarding prediction of postsurgical outcome in patients with intractable temporal lobe epilepsy (Bernhardt et al, 2015;Lin et al, 2005). In a homogenous group of unilateral MTLE patients with histologically proven HS, compared to seizure-free patients, patients with continuing seizures after surgery had greater diffuse ipsilateral hippocampal atrophy and localized contralateral atrophy in the anterior and lateral aspects of the hippocampus.…”

“…In a homogenous group of unilateral MTLE patients with histologically proven HS, compared to seizure-free patients, patients with continuing seizures after surgery had greater diffuse ipsilateral hippocampal atrophy and localized contralateral atrophy in the anterior and lateral aspects of the hippocampus. These atrophic regions in ipsilateral as well as contralateral hippocampus may imply increased epileptogenicity and contribute to poorer surgical outcomes (Lin et al, 2005). In a more recent, sophisticated study, 4 distinct patterns were identified based on a data-driven pattern classification algorithm in a group of surgically treated patients with unilateral temporal lobe epilepsy (Bernhardt et al, 2015).…”

Brain Mapping as a Tool to Study Neurodegeneration

“…85 A surface-based cortical thickness study analyzed the preoperative MRI scans of seizure-free MTLE patients who underwent anteromesial temporal lobectomy in comparison to age-matched controls. The patient group showed cortical thinning in the frontal poles and frontal opercular, orbitofrontal, lateral temporal, and occipital areas.…”

“…Patients with a longer duration of illness showed greater atrophy of the superior frontal and parahippocampal gyri ipsilaterally. 85 The human immunodeficiency virus (HIV) is readily detected in brain tissue of seropositive patients. Sometimes the infection is latent and patients are asymptomatic; at other times patients may suffer from any or all of dementia, encephalopathy, demyelination, Parkinsonism or other movement disorders, sleep abnormalities, and opportunistic CNS infections.…”