Time intensity curve in primary solid hepatic lesions: Does it provide objectivity to otherwise subjective interpretation?

Abstract

Aims and Objectives: Magnetic resonance imaging (MRI) is able to characterize the primary solid hepatic lesions well and dynamic contrast enhanced MRI (DCE-MRI) further improves the diagnostic yield. However, the interpretation of enhancement pattern of a lesion by visual method or eyeballing is quite subjective and is prone to observer error. Time intensity curve (TIC) which plots the signal intensity values in tumor over time provides objectivity in interpretation of DCE-MRI images. Therefore, the aim of this study was to determine the pattern of TIC in primary solid hepatic lesions using DCE-MRI. Method: All cases found to have solid hepatic lesions on ultrasound from January 2017 to December 2018 were included in the study. These cases were subjected to DCE-MRI. Results: Type III-TIC was seen in 30 (93.8%) of cases of hepatocellular carcinoma (HCC), whereas only 2 (6.2%) of cases showed type II curve with χ2 = 43.9848, P < 0.01. Focal Nodular Hyperplasia (FNH) showed type II TIC in 8 (80%) of cases and type III curve in 2 (20%) of cases with χ2 = 34.0052, P < 0.01. Hemangioma showed type I TIC in 14 (93.3%) of cases and type II curve in 1 (6.7%) of cases with χ2 = 44.6185, P < 0.01. Cholangiocarcinoma showed type I TIC, χ2 values could not be determined due to inadequate sample size. Conclusion: TIC provides an objectivity by constructing a time vs signal intensity curve and is less prone to observer error. Therefore, it is recommended that TIC be included in the MRI protocol for evaluating solid hepatic lesions.