[Hepatic perfusion CT imaging analyzed by the dual-input one-compartment model].

Aim: To improve liver-perfusion imaging by using the dual-input one-compartmental model.

Methods: Single-level dynamic computed tomography (dynamic CT) was taken at the height of the hepatic hilum after a rapid intravenous injection using 40 ml of iodinated contrast material. From the time-density curve of each pixel on CT, we calculated blood-flow rate constants of liver inflow and outflow. For inflow, two constants were calculated at arterial and portal veins. We postulated that blood flow between hepatic vessels and the hepatic parenchyma could be analyzed by using the calculated constants, and made equations for liver perfusion mapping. The perfusion images obtained by this method were compared with those made by the maximum slope method.

Results: We applied the method to a patient with hepatolithiasis. On dynamic CT, there was an abnormal enhancement pattern in the posterior segment of the liver. Perfusion CT images made by the dual-input one-compartment model demonstrated abnormal portal perfusion of the liver. In contrast, those made by the maximum-slope method did not represent the perfusion pattern well.

Conclusion: The dual-input one-compartmental model makes it possible to obtain more detailed information on liver hemodynamics.