Detection of Total Parenteral Nutrition-Induced Fatty Liver Infiltration in the Rat by in Vitro Proton Nuclear Magnetic Resonance

In an effort to determine if NMR techniques might be used to detect TPN-induced hepatic steatosis, the NMR spin-lattice (T1) and spin-spin (T2) relaxation times were measured on liver tissue from rats who received one of five dietary regimens: (1) 100% of nonprotein calories as lipid (Fat); (2) a mixture of 50% lipid and 50% glucose nonprotein calories (50/50); (3) 100% of nonprotein calories as glucose (CHO); (4) intravenous saline and standard laboratory rat chow (Saline); and (5) rat chow alone (Oral). The parenteral diets were isonitrogenous and isocaloric. Serum liver function tests were also measured. Animals in the Fat and 50/50 groups had the greatest amounts of liver fat and significantly longer T1 and T2 times (p < 0.01) than any other group. Furthermore, the correlation of T2 time with liver fat content (r = 0.82) was far superior (p < 0.001) to that of serum SGPT (r = 0.48) which was the only liver function test which correlated significantly with liver fat content. In a multiple linear regression analysis, T1 and T2 predicted liver fat content with an r value of 0.84 (p < 0.001). These data suggest that in vivo NMR imaging techniques might be used to detect TPN-induced fatty infiltration of the liver noninvasively. (Journal of Parenteral and Enteral Nutrition 10:177-183, 1986).