Abstract #3328

MR Spectroscopy of GABA and Other Brain Metabolites in Smelters Exposed to Manganese

Ulrike Dydak^1,2, Liling Long³, Henry Zhu⁴, Wenmei Li³, Yueming Jiang⁵, Jian Chen⁶, X. Fu¹, Shuguang Hu⁷, Richard A.E. Edden⁸, Dieter Meier⁹, Michael Aschner¹⁰, James Murdoch¹¹, Wei Zheng¹

¹School of Health Sciences, Purdue University, West Lafayette, IN, USA; ²Dep. of Radiology, Indiana University School of Medicine, Indianapolis, IN, USA; ³Dep. of Radiology, Guangxi Medical University, Nanning, China; ⁴Dep. of Radiology, Johns Hopkins University, Baltimore, MD, USA; ⁵Dep. of Occup. Health and Toxicology, Guangxi Medical University, Nanning, China; ⁶Guizhou Inst. of Occup. Safety and Health, Zunyi, China; ⁷Philips Healthcare, China; ⁸Schools of Biosciences and Chemistry, Cardiff University, UK; ⁹Inst. for Biomed. Engineering, ETH and University Zuerich, Switzerland; ¹⁰Dep. of Pediatrics, Vanderbilt University, Nashville, TN, USA; ¹¹Philips Healthcare, Cleveland, OH, USA

GABA-edited magnetic resonance spectroscopy (MRS) in the basal ganglia was combined with single voxel MRS of five different brain areas and high-resolution 3D T1-weighted imaging at 3T to assess changes in neurotransmitters and other brain metabolites, as well as the spatial distribution of T1 hyperintensities due to occupational manganese exposure in a cohort of smelters. Extensive signal hyperintensities in globus pallidus, striatal and midbrain regions were found in 8 out of 10 exposed subjects. Findings on changes in metabolism include significantly increased GABA/Cr in the thalamic area of the exposed subjects, as well as decreased NAA/Cr in frontal cortex (p<0.05).