Role of MRI in Evaluation of Focal Liver Lesions: A Cross-sectional Study

Abstract

Introduction: The non-invasive diagnosis of liver lesions is usually achieved with contrast material-enhanced computed tomography and Magnetic Resonance (MR) imaging. Dynamic three dimensional gradient-recalled-echo MR imaging provides dynamic contrast-enhanced thin-section images with fat saturation and a high signal-to-noise ratio and is excellent for the evaluation of various focal hepatic lesions. Aim: To explore the effectiveness and hence the clinical utility of plain and contrast MR characterisation of focal hepatic lesions in patients and their correlation with the histopathological findings. Materials and Methods: The present study was a multicenteric study done on both Inpatients and Outpatients of Department of Radiology of Tertiary care hospitals in Bengaluru, from January 2020 to August 2020. A total of 42 patients diagnosed with focal liver lesions by Ultrasonography were included in this study. Plain MRI study was done by using spin echo technique and contrast MRI study was done after rapid bolus injection (0.1 mmol/kg body weight) of gadolinium dimeglumine. Pathological and post-operative histopathological findings were noted. Microsoft excel software was used for data analysis and tables were prepared for comparison of collected data. Specificity and sensitivity were calculated for diagnostic accuracy of MRI. Results: This study included forty-two patients in total, twenty-five male and seventeen female patients, in age group of 15 to 84 years with a mean age of 48 years. Metastasis and Hepatocellular Carcinoma (HCC) were most common malignant lesions in liver while Hemangiomas were most common benign lesions followed by simple and complex cysts and hepatic adenoma. The present study calculated the specificity and sensitivity of MRI of focal hepatic lesions and correlated the findings clinically, pathologically and histopathologically. The specificity of MRI for characterisation of focal liver disease was high (90.4%). Specificity of MRI for HCC was found to be 96.7 % and that for metastasis was 97% while sensitivity for Haemangiomas is found to be 100%.MRI is superior compared to other modalities like ultrasound and CT in having high spatial resolution. Multiple sequences like T1, T2 and fat suppression techniques like IN PHASE, OUT OF PHASE helps in demonstrating lesion characters like architecture, margin, haemorrhage, fat component and vascular invasion of the lesions. Conclusion: MRI is valuable for the characterization of focal liver lesions detected on Ultrasonography. Basic MRI sequences along with chemical shift imaging sequences and dynamic contrast imaging has significant role in characterising the focal liver lesions. Despite that, It should be the modality choice for the lesions which are undetected or doubtful on ultrasound and CT examinations.