Histopathological validation and clinical correlates of hippocampal subfield volumetry based on T2-weighted MRI in temporal lobe epilepsy with hippocampal sclerosis

Glucose Metabolism of Hippocampal Subfields in Medial Temporal Lobe Epilepsy

“…We first included patients who underwent resection surgery for drugresistant MTLE with a pathological diagnosis of HS. Note that the inclusion criteria included both preoperative 3T high-resolution MRI and 18 F-FDG PET. For a portion of these patients, we were able to obtain postoperative follow-up data for at least 1 year, which enabled us to determine postoperative seizure outcomes based on Engel classification.…”

“…The patients refrained from ingesting any food or drink (including IV glucose-containing fluid) for at least 6 hours before the PET examination. To prevent the administration of 18 F-FDG during or shortly after a seizure, efforts were made to ensure that there were no clinical or electroencephalographic signs of a seizure for at least 2 hours before administering the 18 F-FDG tracer. To avoid the effects of hyperglycemia on 18 F-FDG uptake in the brain, blood sugar levels were monitored to ensure that they remained below 150 mg/dL.…”

“…Patients and Methods: This study examined 29 patients (18 females; 15-58 years) diagnosed with HS who underwent surgery for drugresistant epilepsy. FreeSurfer 7.1.1 was used in the processing of MRI data and 18 F-FDG PET scans to derive volumetric data and the FDG SUVr in the whole hippocampus and hippocampal subfields, including the CA1, CA2-4, granule cell and molecular layer of the dentate gyrus (GC-ML-DG), and subiculum. Asymmetries in the volume and SUVr between the 2 sides from the subfields of the hippocampus were defined in terms of an asymmetry index.…”

“…7 Hippocampal subfield analysis based on PET-MRI has proven far more effective than global hippocampal assessments in detecting pathological changes associated with AD. 8 In cases of medial temporal lobe epilepsy (MTLE), 18 F-FDG PET has been used to observe brain glucose metabolism and lateralize seizure focus in assessing the suitability of patients for epilepsy surgery and predicting surgical outcomes. 9,10 Neuroimaging has seldom been used to observe glucose metabolism in the hippocampal subfields of patients with MTLE.…”

Apolipoprotein ε4 modifies obesity-related atrophy in the hippocampal formation of cognitively healthy adults

“…The CA1, CA2/3, DG and subiculum subfields were segmented with two publicly available, automated protocols that make use of T 1 - and T 2 -weighted hippocampal images: The Bayesian inference labeling methods implemented in FreeSurfer 6.0 ( Iglesias et al., 2015 ) and the Automatic Segmentation of Hippocampal Subfields (ASHS) that utilizes multi-atlas segmentation and machine learning techniques ( Yushkevich et al., 2015b ). Both protocols have been validated with histopathological evidence in patients with epilepsy ( Menzler et al., 2021 ; Mizutani et al., 2021 ). Employing both ASHS and FreeSurfer allowed us to assess whether the choice of protocol for the labelling of hippocampal subfields had an impact on the analysis of risk effects ( Yushkevich et al., 2015a ).…”