The Portal Component of Hepatic Perfusion Measured by Dynamic CT (An Indicator of Hepatic Parenchymal Damage)

Abstract

CT can measure absolute hepatic arterial andportal venous perfusion; pilot data suggests these areraised and lowered, respectively, in cirrhosis. Thisstudy examined the value of functional CT in assessing cirrhosis, using the prothrombin ratio (PTR) asa marker for hepatic parenchymal damage. Twenty subjectswith viral-induced cirrhosis (11 men and 9 women; 55.41± 7.86 years) and 14 controls (8 men and 6 women; 48.36 ± 17.67 years) werestudied. A single section through the liver was scannedafter bolus intravenous injection of 40 ml ioversol 320mgI/ml. Hepatic arterial and portal perfusion wasmeasured using a previously described technique. Hepaticportal perfusion was decreased in patients (0.66± 0.21 ml/min/ml) compared with controls (1.11± 0.23 ml/min/ml; P < 0.0001). A strongcorrelation was seen between PTR and portal perfusion (r =0.662, P = 0.0038) in cirrhotics. Hepatic arterialperfusion did not differ between patients (0.088± 0.082 ml/min/ml) and controls (0.091 ±0.067), and did not correlate with PTR. In conclusion,portal perfusion is reduced in cirrhosis, and thisreduction correlates with PTR. It could thus be used asa marker of hepatic parenchymal damage. This technique may be useful in the follow-up of chronic liverdisease, potentially reducing the need for serial liverbiopsy.