Investigation of in-vivo GABA+ and Glutamate levels in patients with drug resistant unilateral temporal lobe epilepsy using MEGA-PRESS and correlates with clinical semiology
N. Pradhan , Manoj Kumar , M. Sandhya , P. Bairwa , PV Prathyusha , K. Raghavendra , LG Viswanathan , A. Asranna , RC Mundlamuri , DK Deelchand , Jitender Saini , Rose Dawn Bharath , Sanjib Sinha
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引用次数: 0
Abstract
Background
In this study, we used in vivo MEGA-PRESS spectroscopy to investigate GABA and Glu levels in patients with drug-resistant unilateral temporal lobe epilepsy (TLE) and also look for correlation between neurometabolites and clinical semiology assessed by other modalities.
Materials and methods
Twenty-five patients with TLE underwent MRS data acquisition on a 3.0 T MRI. Bilateral single-voxel MEGA-PRESS data was acquired from mesial temporal lobes, and data was post-processed using MRSpa and LC-Model for computing neurometabolites concentration. Tissue segmentation from spectroscopic voxel was performed for tissue metabolite and CSF correction. Statistical analysis was performed to analyze differences in neurometabolic between affected and normal-sides and clinical correlations.
Results
GABA, Glu, NAA, Cr, and Cho neurometabolites were computed. The group-wise statistical comparison revealed a significantly reduced NAA level from the affected compared to normal-side of the hippocampus (p-value=0.039). We observed reduced GABA (p-value=0.07) values and hippocampal volume (p-value<0.001) were observed from the affected side. A significant negative correlation was noted between affected-side hippocampal volume and NAA concentration (rho=-0.497, p-value=0.05). Glu/NAA ratios from both affected (rho=-0.692, p-value=0.012) and normal-sides (rho=-0.608, p-value=0.016) of the hippocampus were negatively correlated with age. Concordance between neurometabolites with video-EEG for lateralization demonstrates correct classification percentage for GABA was 86.7 %, indicating that there is an 86.7 % chance that GABA will be able to lateralize the unaffected side as detected by VEEG.
Conclusion
A novel exploratory study demonstrates an alternation of in-vivo GABA and Glu levels and hippocampal volume. This study may provide a direction for utilizing MEGA-PRES as a presurgical tool for assessing in-vivo neurometabolic profiles and add to the knowledge of the role of GABA and Glu in epilepsy and its interplay.
期刊介绍:
Epilepsy Research provides for publication of high quality articles in both basic and clinical epilepsy research, with a special emphasis on translational research that ultimately relates to epilepsy as a human condition. The journal is intended to provide a forum for reporting the best and most rigorous epilepsy research from all disciplines ranging from biophysics and molecular biology to epidemiological and psychosocial research. As such the journal will publish original papers relevant to epilepsy from any scientific discipline and also studies of a multidisciplinary nature. Clinical and experimental research papers adopting fresh conceptual approaches to the study of epilepsy and its treatment are encouraged. The overriding criteria for publication are novelty, significant clinical or experimental relevance, and interest to a multidisciplinary audience in the broad arena of epilepsy. Review articles focused on any topic of epilepsy research will also be considered, but only if they present an exceptionally clear synthesis of current knowledge and future directions of a research area, based on a critical assessment of the available data or on hypotheses that are likely to stimulate more critical thinking and further advances in an area of epilepsy research.