Characterisation of Focal Liver Lesions using Diffusion-Weighted Magnetic Resonance Imaging Technique

Abstract

Introduction: Magnetic Resonance Imaging (MRI) is an important imaging modality for assessing and charactersing Focal Liver Lesions (FLLs). Diffusion-Weighted (DW) imaging, a powerful imaging tool, adds valuable information to MRI and provides unique information related to tumour cellularity and the integrity of the cellular membrane. The technique can be widely applied for tumour detection, tumour characterisation, and for monitoring the response to treatment. Aim: To evaluate the role of Diffusion-Weighted Magnetic Resonance Imaging (DW-MRI) in differentiating between malignant and benign FLLs. Materials and Methods: A total of 30 patients with FLLs diagnosed on Multi Detector Computed Tomography (MDCT) were evaluated. Demographic and clinical characteristics of all the patients were noted. Biochemical investigations, histopathological examinations, and radiological investigations, including Contrast-Enhanced Computed Tomography (CECT) imaging and DW-MRI were also performed and recorded. DWMRI was performed with b values of 50, 400, and 800 mm2 /s; and Apparent Diffusion Coefficient (ADC) values were also calculated. SPSS 20.0 was used to analyse the data. Results: Out of 30 FLLs diagnosed, 19 (hepatocellular carcinoma: 11 and metastatic FLLs: 8) were malignant and 11 (haemangiomas: 5, abscesses: 3, simple hepatic cysts: 2, focal nodular hyperplasia: 1) were benign. Among these, all the malignant lesions and three benign lesions, which showed typical imaging findings of abscess, displayed restricted diffusion. The cut-off mean ADC value: 1.077×10-3 sq. mm/sec was used to differentiate malignant and benign FLLs. The mean ADC value of benign FLLs was 1.372±0.308×10-3 sq. mm/s and mean ADC value of malignant lesions was 0.878±0.147×10-3 sq. mm/s. Conclusion: Overall, DW-MRI combined with ADC can be used to detect FLLs and serves as a diagnostic tool for differentiating them as malignant and benign.

Keywords

• contrast-enhanced multidetector computed tomography
• diagnostic tool
• diffusion-weighted imaging
• tumour detection