Siderotic nodules in the cirrhotic liver at MR imaging with explant correlation: No increased frequency of dysplastic nodules and hepatocellular carcinoma

PURPOSE: To determine the sensitivity of magnetic resonance (MR) imaging fo r detection of siderotic nodules in patients with cirrhosis and whether the frequency of hepatocellular carcinoma (HCC) and dysplastic nodules is grea ter if siderotic nodules are present. MATERIALS AND METHODS: MR imaging (1.5 T) was performed within 0-117 days ( mean, 30 days) before liver transplantation in 77 patients. Two readers ret rospectively evaluated gradient-echo (CRE) (echo time [TE], greater than or equal to9 and 4-5 msec) and turbo short inversion time inversion-recovery or T2-weighted images for low-signal-intensity nodules. Whole-explant patho logic correlation was available in every case. RESULTS: At explantation, 28 (36%) of 77 patients had HCC, 25 (32%) had dys plastic nodules, and nine (12%) had both; 35 (45%) patients had siderotic n odules. The sensitivity of GRE imaging with 9-msec or longer TE for the det ection of siderotic nodules was 80% (28 of 35) but decreased to 31% (11 of 35) with 4-5-msec TE. Frequency of HCC was not significantly higher (P = .2 7) in patients with (43% [15 of 35]) than in patients without (31% [13 of 4 2]) siderotic nodules. Frequency of dysplastic nodules also was not signifi cantly higher (P = .42) in patients with (37% [13 of 35]) than in patients without (29% [12 of 42]) siderotic nodules. CONCLUSION: Sensitivity of MR imaging for the detection of siderotic nodule s was improved with use of GRE pulse sequences with longer TEs of 9 msec or greater (80%) versus 4-5 msec (31%); however, there was no significant inc reased frequency of HCC or dysplastic nodules in patients with pathological ly proved siderotic nodules.