The study on sectional anatomy and imaging of accessory hepatic veins.

To evaluate the distribution and clinical value of accessory hepatic veins (AHVs), we investigated the number and caliber of the AHVs and the angles between the shafts of AHVs and inferior caval vein. We analyzed the anatomical dissections, serial transverse and coronal sections (0.1-0.2 mm) of a frozen liver, and the ultrasonographical and enhanced CT images of healthy patients. We found that: (1) Most of the angles between the AHVs and inferior caval veins on the thin sections (78%) and liver dissections (72%) were acute (P < 0.01), while the AHVs with right angles had significantly larger average calibers (P < 0.05). However, on the contrary, most of the angles between the AHVs and inferior caval veins were right angles as observed in ultrasonography (89%) and spiral CT images (83%) (P < 0.01). The angle parameters appear to be more selective when displaying the AHVs on ultrasonography and spiral CT images. (2) The presentation rates of the AHVs in ultrasonic and spiral CT images were much lower than those of the anatomical dissections (P < 0.01). (3) There were no apparent differences in displaying right inferior hepatic veins between ultrasonography and spiral CT (P > 0.05). However, the presentation rate of small AHVs was much lower in spiral CT images (P < 0.05). (4) The ultrasonographical and spiral CT scans provide effective reference for the diagnosis of Budd-child syndrome, hepatectomy, especially liver hanging maneuver.