Gadoxetic acid-enhanced MRI for T-staging of gallbladder carcinoma: emphasis on liver invasion

Objective:To evaluate the diagnostic performance of gadoxetic acid-enhanced MRI with an emphasis on the usefulness of the hepatobiliary phase (HBP) in T-staging of gallbladder carcinoma.Methods:66 patients with surgically confirmed gallbladder carcinoma underwent MRI. Two radiologists independently reviewed two sets of gadoxetic acid-enhanced MRI without and with the HBP. Local tumour spread was evaluated according to T-staging, and the results were compared with pathological findings. The diagnostic performance of two image sets to differentiate each T-stage was compared.Results:The sensitivities of MRI with the HBP to differentiate T1 vs ≥T2 lesions, ≤T2 vs ≥T3 lesions and ≤T3 vs T4 lesions were 96.3%, 85.7% and 100% for Observer 1 and 92.6%, 95.2% and 100% for Observer 2, respectively (p < 0.0001). By adding the HBP, the sensitivities to differentiate ≤T2 vs ≥T3 lesions were increased from 66.7% to 85.7% for Observer 1 and from 81.0% to 95.2% for Observer 2, although there was no significant difference...