Hippocampal Sclerosis in Temporal Lobe Epilepsy: Findings at 7 T
- 1 October 2011
- journal article
- Published by Radiological Society of North America (RSNA) in Radiology
- Vol. 261 (1), 199-209
- https://doi.org/10.1148/radiol.11101651
Abstract
Purpose To determine if ultrahigh-field-strength magnetic resonance (MR) imaging can be used to detect subregional hippocampal alterations. Materials and Methods Subjects provided written consent to participate in this prospective institutional review board–approved HIPAA-compliant study. T1- and T2-weighted 7-T brain MR images were acquired in 11 healthy subjects and eight patients with temporal lobe epilepsy (TLE). In all subjects, images were qualitatively examined for evidence of hippocampal atrophy, signal change, and malrotation with the Bernasconi definition, and digitations of the hippocampal heads were counted (agreement was measured with the κ statistic). Data were analyzed quantitatively with manual subregional hippocampal body segmentation. Subregional data in individual subjects with TLE were compared with data in control subjects to detect deviation from the control range for volume measures on each side and with asymmetry indexes. Results All eight patients with TLE had hippocampal abnormalities on the epileptogenic side. Subregional analysis revealed selective lateral Ammon horn atrophy in six patients and diffuse Ammon horn and dentate gyrus atrophy in one patient. Paucity of hippocampal digitations occurred on the epileptogenic side in all patients with TLE and also on the contralateral side in three patients (interrater κ value, 0.80). Hippocampal malrotation was observed in three patients with TLE and four control subjects. Conclusion Ultrahigh-field-strength MR imaging permitted detection of selectively greater Ammon horn atrophy in patients with TLE and hippocampal sclerosis. Paucity of digitations is a deformity of the hippocampal head that was detected independent of hippocampal atrophy in patients with mesial TLE. © RSNA, 2011 Supplemental material: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.11101651/-/DC1This publication has 35 references indexed in Scilit:
- Human Hippocampal Subfields in Young Adults at 7.0 T: Feasibility of ImagingRadiology, 2010
- Hippocampal volume assessment in temporal lobe epilepsy: How good is automated segmentation?Epilepsia, 2009
- Automatic segmentation of the hippocampus and the amygdala driven by hybrid constraints: Method and validationNeuroImage, 2009
- T1 weighted brain images at 7 Tesla unbiased for Proton Density, T2⁎ contrast and RF coil receive B1 sensitivity with simultaneous vessel visualizationNeuroImage, 2009
- High-field MRI of brain cortical substructure based on signal phaseProceedings of the National Academy of Sciences of the United States of America, 2007
- Automatic detection and quantification of hippocampal atrophy on MRI in temporal lobe epilepsy: A proof-of-principle studyNeuroImage, 2007
- Analysis of shape and positioning of the hippocampal formation: an MRI study in patients with partial epilepsy and healthy controlsBrain, 2005
- Quantitative neuropathology and quantitative magnetic resonance imaging of the hippocampus in temporal lobe epilepsyAnnals of Neurology, 1997
- Characteristics of medial temporal lobe epilepsy: I. Results of history and physical examinationAnnals of Neurology, 1993
- Magnetic resonance imaging in temporal lobe epilepsy: Pathological correlationsAnnals of Neurology, 1987