FOCAL LIVER-LESIONS - CHARACTERIZATION WITH TRIPHASIC SPIRAL CT

PURPOSE: To assess whether triphasic spiral CT enables characterizatio n of a wide range of focal liver lesions. MATERIALS AND METHODS: One h undred five patients with suspected focal liver disease underwent trip hasic liver CT. After injection of contrast material, the liver was sc anned in arterial (scanning delay, 22-27 seconds), portal (scanning de lay, 49-73 seconds), and equilibrium (scanning delay, 8-10 minutes) ph ases. Enhancement of each lesion in each phase was evaluated, and the lesions were tabulated according to one of 11 enhancement patterns. RE SULTS: In 94 patients, 375 liver lesions were detected. The nature of the lesion was confirmed in 326 lesions (87%). Six of 11 enhancement p atterns were always due to benign disease and caused by areas with hyp er- or hypoperfusion, hemangiomas, cysts, focal nodular hyperplasias, or benign but nonspecified lesions. Two of 11 patterns were always due to malignant disease, and one pattern was due to malignant disease in 38 (97%) of 39 patients with known malignancy elsewhere or with chron ic liver disease. The other two patterns were seen in metastases and p artly fibrosed hemangiomas. CONCLUSION: Triphasic liver CT enables cha racterization of a wide range of focal liver lesions, including the be nign liver lesions that occur most frequently.