Comparison of the DWI and Gd-EOB-DTPA-enhanced MRI on assessing the hepatic ischemia and reperfusion injury after partial hepatectomy

Abstract Objective To compare two different imaging media, diffusion weighted imaging (DWI) with apparent diffusion coefficient (ADC) and Gd-EOB-DTPA-enhanced magnetic resonance imaging (MRI) with perfusion parameters K trans , K ep , and relative contrast enhancement index (RCEI), in assessing the liver function via ischemia/perfusion injury (IRI) + partial hepatectomy rat model. Methods Rats underwent 0, 30 and 60 min of ischemia/reperfusion with 30% of hepatectomy before subjected to Gd-EOB-DTPA-enhanced MRI in addition to 99m Tc-GSA scintigraphy. For 99m Tc-GSA scintigraphy test, the receptor index LHL15, modified receptor index and the blood clearance index HH15 were recorded. Apparent diffusion coefficient (ADC) was evaluated by using both mono- and bi-exponential models, and perfusion parameters K trans , K ep , and RCEI were measured. Liver function is tested by measuring activity of serum ALT, AST and PT. Histological analysis was performed by H&E and Ki-67 staining. Results 99m Tc-GSA dynamic imaging analysis demonstrated that LHL15 was increased and HH15 was decreased as the extension of ischemia/reperfusion time. ADC value estimated by MRI was significantly increased (P  trans value was gradually and significantly decreased (P   0.05) in K ep value between at 30 min and 60 min IRI, and RCEI value was significantly higher (P  Conclusion Fast ADC bi-exponential model in DWI and RCEI in Gd-EOB-DTPA-enhanced MRI showed the good correlation in assessment of liver function after partial hepatectomy, showing consistency with our histological findings. The K trans in Gd-EOB-DTPA-enhanced MRI could be a potent parameter for assessing the early ischemic injury, but not the severity of the hepatic injury, in accordance with the correlation with our biochemical findings.