Value of MR Imaging after CT in Patients with Focal Hepatic Lesion

Kim, Kyeong Ah; Lim, Jae Hoon; Choi, Sang Hee; Lee, Soon Jin; Paik, Chul H; Cho, Jae Min

Abstract

PURPOSE: To determine the usefulness of magnetic resonance imaging (MRI) after computed tomography (CT) inpatients with focal hepatic lesion.
MATERIALS AND METHODS
We evaluated 100 patients with 103 focal hepaticlesions. The diagnosis of each lesion was made pathologically (n=19), or radiologically and clinically (n=84), andthe findings were as follows: he-mangioma (n=53), hepatocellular carcinoma (n=17), metastasis (n=10), cyst (n=5),regenerative nodule (n=3), and adenomatous hyperplasia (n=3). The patients underwent conventional CT (n=25),two-phase spi-ral CT (n=17) or three-phase spiral CT (n=61). MRI was performed using conventional T1- andT2-weighted imaging and dynamic contrast enhancement. The value of MRI after CT was assigned to one of fourgrades, according to the consensus of three radiologists: grade I (decisive), grade II (helpful), grade III (notadditional), or grade IV (confused).
RESULTS
The outcome of MRI of 103 lesions was grade I in 14 cases(14%), IIin 34 (33%), III in 49 (48%), and IV in 6 (6%). MRI was not helpful (grade III or IV) in 40% (10/25), 47% (8/17),and 61%(31/61) of lesions after conventional, two-phase spiral, and three-phase spiral CT, respectively. Grade IIIor IV lesions were present in 45% of hemangiomas (24/53), 59% of hepatocellular carcinomas (10/17), and 80% ofcases in which metastasis had occurred(8/10).
CONCLUSION
MRI after CT in patients with focal hepatic lesion washelpful in less than half of all cases. It was particularly valuable for patients who did not undergo three-phasespiral CT and in whom hemangioma was suspected.