Asian Journal of Advances in Medical Science

Aims: To evaluate the diagnostic role of the enhancement pattern of focal liver lesions on triphasic Computed Tomography (CT) in the arterial, portal venous, and delayed phases at tertiary care centre.

Study Design: Prospective observational study.

Place and Duration of Study: Department of Radiodiagnosis at S. S. Institute of Medical Science and Research Centre (SSIMRC) Davangere, Karnataka.

Methodology: 50 patients (Age range: 41-60years) presenting with suspected liver disease referred for triphasic CT scan. A dynamic assessment of all reconstructed CT images was conducted. Initially, the unenhanced, Hepatic Arterial Phase (HAP), and Portal Venous Phase (PVP) images were evaluated to identify any focal liver lesions. Following this, each lesion's appearance across different phases (unenhanced, HAP, PVP, and delayed) was analyzed based on its enhancement characteristics and attenuation in comparison to the surrounding liver tissue in each phase. Lesions were broadly categorized as either hypervascular or hypovascular relative to the liver parenchyma. Each imaging phase was first assessed independently, followed by a combined interpretation of all phases.

Results: The top three ranked focal lesions of liver appeared in triphasic CT were found to be hydatid cyst (22%), hemangioma (20%), and hepatocellular carcinoma (18%). Contrast triphasic CT scan diagnostic work-ups showed appearance of enhanced and non-enhanced focal lesions of liver in 32 and 18 patients respectively. Majorly arterial/venous/delayed-hypo/hypo/hypo pattern constitutes lesions of simple cysts, hydatid cysts, and metastases in 4, 11, and 3 patients respectively. Majorly, the homogenous enhancement patterns were appeared on triphasic CT scan, and which are diagnosed with hepatocellular carcinoma, metastasis, and haemangioma in 3, 4, and 3 patients respectively.

Conclusion: multidetector triphasic CT allows highly precise imaging during the arterial, venous, and delayed phases of hepatic enhancement. Optimal acquisition timing in combination with thinner collimation permits improved lesion detection and will also show improved characterization of lesions.