Abstract
Multidetector row computed tomography (CT) scanners perform dynamic scanning and have a wide scan range. Time-resolved three-dimensional CT (i.e., 4D CT) has recently enabled visualization of flow in neurovascular vessels. We hypothesized that 4D CT technology would be a useful and non-invasive method for visualizing the flow dynamics of the portal circulation. The aim of this study was to evaluate the technical feasibility of 4D CT for visualizing flow dynamics in the portal circulation using 320-detector-row CT. 4D CT images of 18 consecutive patients with portal circulation including gastrorenal shunt were retrospectively evaluated for their ability to generate flow dynamics of the portal circulation. Flow dynamics could be visualized by 4D CT in 68 of the 72 vessels in the portal vein, splenic vein, superior mesenteric vein, and gastrorenal shunt. Flow direction could not be identified in four vessels, all of them being superior mesenteric veins. Flow direction was recognized on 4D CT in the 68 vessels of the portal circulation. A preliminary validation study revealed that flow direction of all 19 vessels in the portal circulation had concordance between 4D CT and color Doppler ultrasound. 4D CT could visualize flow dynamics of the portal circulation.
Highlights
Portal hypertension leads to serious complications, including bleeding from gastroesophageal varices, ascites, and portosystemic encephalopathy, in patients with hepatic cirrhosis
Flow dynamics could be visualized by 4D computed tomography (CT) in 68 of the 72 vessels in the 18 patients
In the 68 vessels that could be visualized by 4D CT, both readers recognized flow direction from the flow dynamics of the portal circulation on 4D CT
Summary
Portal hypertension leads to serious complications, including bleeding from gastroesophageal varices, ascites, and portosystemic encephalopathy, in patients with hepatic cirrhosis. Hepatic venous pressure gradient is the gold standard method for the diagnosis of portal hypertension [1]; as it is measured by catheter, it is highly invasive. Endoscopic evaluation of varices is an indirect method of assessing portal hypertension, but it is an invasive technique. Noninvasive techniques proposed in recent decades for the measurement of portal hypertension include flow imaging using ultrasound (US) or magnetic resonance imaging (MRI) [1,2,3,4,5,6]. Doppler US and two-dimensional phase-contrast MRI are widely performed and well validated for measuring velocity and flow direction [7,8,9].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
