Abstract #2393

In Vivo Optimisation of GABA Measurements in the Hippocampus Using MEGA-PRESS at 3T

Bhavana S. Solanky¹, Niamh Cawley², Anna Graca¹, Richard Anthony Edward Edden³,⁴, Olga Ciccarelli², Claudia Angela M. Wheeler-Kingshott¹

¹NMR Research Unit, Queen Square MS Centre, Department of Neuroinflammation, UCL Institute of Neurology, London, United Kingdom; ²Department of Brain Repair and Rehabilitation, UCL Institute of Neurology, London, United Kingdom; ³Russell H Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, MD, United States; ⁴F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, United States

GABA is the main inhibitory neurotransmitter. Using MEGA-PRESS editing techniques GABA measurements in many areas of the brain but have been reported mainly limited to large voxels in areas of B0 homogeneity. 1H MRS measures in the hippocampus, which has an important role in memory and cognitive function, are limited due its small size, strong susceptibility changes and the pulsatile flow of cerebrospinal fluid. This study successfully measured GABA in vivo in the hippocampus at 3T using cardiac triggered MEGA-PRESS. A mean value of 1.7mM was found. This protocol allows reliable absolute measures of GABA in the hippocampus.