The prevalence and variations of inferior right hepatic veins on contrast-enhanced helical CT scanning.

PURPOSE: To present the prevalence and variations of inferior right hepatic veins (IRHVs) on contrast-enhanced helical computed tomography (CEHCT) scans. MATERIALS AND METHODS: The routine abdominal CEHCT scans of 349 patients were reviewed. Three hundred and eight patients (88.2%) were included in the study. Of the 349 patients, 41 (11.8%) were excluded from the study because of improper opacification of hepatic veins and right hepatic lobe lesions which made difficult the optimal visualization and assessment of IRHVs. The mean age of 308 patients was 43 years (range 3-97 years). One hundred and forty-three patients (46.4%) were men and 165 (53.6%) women. Scans were examined whether the IRHVs were demonstrated or not and classified according to their numbers, levels, diameters, and joinings to inferior vena cava (IVC). RESULTS: Of the 308 patients, 65 (21.1%) had one or two IRHVs. Fifty-four patients (83.1%) had only one IRHV and 11 (16.9%) patients had two. More than two IRHVs were not seen in any patient. Eight (72.7%) of 11 double IRHVs joined the IVC at the same level and others (27.3%) did not. There was no truncal opening to the IVC. In five patients (7.7%) the IRHV were large (> or =0.5 cm). CONCLUSION: The presence of IRHVs is common and routine CEHCT scanning is efficacious in assessment of IRHVs.