History
A 53-year-old female patient, complaining of abdominal wall varices, progressive abdominal tenderness and fatigue for the past two years, came to the hospital for a check-up. A triple-phase (arterial, portal-venous and delayed) contrast-enhanced abdominal CT examination was requested and performed for assessment.
Diagnosis
CT images, acquired in the portal-venous phase, showed no contrast in the hepatic vein (HV), the suprarenal
and hepatic segment of the IVC, in consistence with a delayed venous return. In the delayed phase, these
vessels were filled with contrast and a severe, localized, supra-hepatic stenosis of the inferior vena cava (IVC) was seen along with a small calcification, suggesting a consequential chronic thrombosis. A single, dilated hepatic vein with three branches drained into the IVC. Splenomegaly and abdominal wall varices were also present. The azygos vein and its tributaries, the right posterior intercostal veins, were dilated. There were no signs of portal hypertension, nor hepatic cirrhosis or ascites. CT findings suggested a Budd-Chiari syndrome (BCS). Subsequently, the patient underwent therapeutic venous balloon angioplasty of the IVC, resulting in a successful improvement of her symptoms and abdominal wall varices. A post-procedure ultrasound examination revealed good blood flow signals of the intrahepatic veins and the IVC.
Fig. 1: Obliques MPR images (Fig. 1a & 1b) and cVRT images (Fig. 1c & 1d) show no contrast filling in the HV, the suprarenal and hepatic segment of the IVC, in the portal-venous phase (Fig. 1a & 1c, arrowheads), suggesting a delayed venous return. In the delayed phase (Fig. 1b & 1d), these vessels were filled with contrast and a severe, localized, supra-hepatic stenosis (arrows) of the IVC is seen along with a small calcification (dotted arrows).
Fig. 2: cVRT images show a severe supra-hepatic IVC stenosis with a small calcification (Fig. 2a, arrow). A single, dilated hepatic vein with three branches draining into the IVC is seen. The azygos vein (Fig. 2b, arrow) and its tributaries, the right posterior intercostal veins, are dilated. Splenomegaly and abdominal wall varices are present (Fig. 2c & 2d). The portal veins appear normal.
Fig. 3: Digital subtraction angiogram shows an obstructed supra-hepatic IVC with dilated branches (Fig. 3a). The blood flow is restored after venous balloon angioplasty (Fig. 3b).
Comments
BCS is a rare disease caused by impaired venous outflow from the liver, mostly at the level of the hepatic veins and inferior vena cava. Without treatment, 90% of patients die within 3 years, mostly due to complications from a liver cirrhosis. Imaging is the mainstay of a certain diagnosis. CT is routinely performed to demonstrate the location, extension and severity of the obstruction, and additionally, hepatic structural changes, portal venous system or a secondary pathology. CT is especially advantageous in showing calcifications in the obstructed area, which is an important information for the interventionist so to avoid vessel rupture during angioplasty.
This case was performed with a dual source CT, SOMATOM Force, using a combination of Turbo Flash mode and a low kV setting. The pitch value is set to 1.8, corresponding to a volume coverage speed of 415 mm/s, to acquire the entire abdomen and pelvis in just 1.2 s. The high X-ray tube power at low kV enables the use of a 90 kV setting to enhance the contrast-to-noise ratio (CNR), and it is selected automatically by CARE kV – an automated feature that adjusts the tube voltage tailored to the individual patient, the system capabilities and the clinical task. The reduced exposure time and enhanced CNR contribute to the reduction of radiation dose (7.1 mGy for each phase). A three-dimensional life-like visualization of the location, extension, severity and calcification of the obstruction is demonstrated using cinematic volume rendering technique (cVRT), which facilitates the pre-procedural planning and provides guidance to the interventionist for a successful angioplasty of the IVC.
Examination Protocol