Santosh Kumar Yadav1, Sona Saksena1, Anshu Srivastava2, Arti Srivastava1, Vivek A. Saraswat3, Michael A. Thomas4, Ram Kishore S. Rathore5, Rakesh K. Gupta1
Sixty-three patients with EHPVO having different age groups with 47 age/sex matched controls were studied. Neuropsychological tests, MR imaging, 1H-MR Spectroscopy and blood-ammonia estimation were performed in all subjects. 40% EHPVO patients had MHE who showed significantly increased Mean diffusivity, Glx/Cr, blood-ammonia and GP T1 H in all age groups; however, mIns/Cr was significantly lower only in adults when compared to controls. Mean diffusivity positively correlated with blood-ammonia and Glx/Cr in all age groups. A significant positive correlation was observed between Glx/Cr and blood-ammonia. Increases in Mean diffusivity, Glx/Cr, blood-ammonia and GP T1 H and decrease in mIns/Cr are associated with pathogenesis of MHE in adults with EHPVO. No change of cho/Cr in EHPVO may serve as a diagnostic marker for its differentiation from cirrhosis induced MHE. A significant positive correlation among blood ammonia, Glx/Cr and mean diffusivity indicates that hyperammonia contributes to the generalized low grade cerebral edema.