Role of Doppler Ultrasound and Triphasic CT in Differentiation between Benign and Malignant Portal Vein Thrombosis

Abstract

Abstract Background Portal vein thrombosis is typically a consequence of cirrhosis that already exists, abdominal malignancy, hypercoagulable conditions, or abdominal inflammation. Imaging techniques are used to identify portal vein thrombosis. Once a thrombus has been identified using ultrasound, Doppler ultrasonography can be used to determine if it is benign or malignant. The following step is contrast-enhanced computed tomography or magnetic resonance angiography if more information is needed. If these tests are insufficient, digital subtraction angiography should be carried out. Patients and Methods The study included 40 patients diagnosed by B mode ultrasound to have PVT and referred to the radiology department of the National Hepatology And Tropical Medicine Institute to differentiate between benign and malignant PVT using color Doppler and Triphasic CT. Results those 40 patients were classified according to triphasic CT criteria into 17 patients with benign PVT and 23 patients with malignant PVT which all of them had neovascularity and show early arterial enhancement and delayed wash out. Intra-thrombus pulsatile flow by color Doppler was detected in 19 patients with percentage of agreement 80%, sensitivity of 73.9% and specificity of 88.2%. Conclusion Color Doppler US considered an effective non invasive tool to differentiate between benign and malignant PVT, but it is an operator dependent which need an expertise to detect the vascularity within the thrombus. But is an easy, low cost, available, no contraindications to be done and no exposure to radiation. Although absence of intra-thrombus vasculature doesn`t exclude the malignant nature of the thrombus, and here come the role of Triphasic CT.