Meeting Banner
Abstract #1708

Hyperammonemia and Edema: A DTI Study in the Adult Rat Brain

Nicolas Kunz1,2, Cristina Cudalbu1, Yohan Van de Looij1,2, Petra Hppi2, Stephane Sizonenko2, Rolf Gruetter1,3

1Laboratory of functional and metabolic imaging (LIFMET), Ecole Polytechnique Fdrale de Lausanne, Lausanne, Switzerland; 2Division of Child Growth &Development, University of Geneva, Geneva, Switzerland; 3Department of Radiology, University of Geneva & Lausanne, Geneva & Lausanne, Switzerland

Ammonia is a neurotoxin that is implicated in the pathogenesis of hepatic encephalophaty, which is reported to be responsible for brain edema. It is not yet clear whether brain edema is mostly vasogenic or cytotoxic. The aim of this study was to assess the effects of hyperammonemia on the rat brain by using DTI at 9.4T. This study shows a rapid increase of the ventricle size during the three first hours of infusion along with a decrease in ADC. As the ventricle size gets stabilized after 6h, the ADC keeps on decreasing, indicating the formation of mild cytotoxic edema.