Had ct of liver indicates hepatic portal vein mildly enlarge at 15 cm . is this a sign of cirrhosis ?

Not in normal range: Upper limits of nor\mal is 1.2 cm main portal vein diameter. Distention may indicate blood not flowing noramlly through the liver. Cirrhosis is one cause. The direction of flow and waveform on Doppler ultrasound may be helpful. CT may show collateral vessels, shunts, and other abnormalities. Ask your doctor, about its significance and what other studies might be indicated.