MSCT Portal Vein Angiography In The Analysis Of Variation Of The Portal Vein

[Objective] To analyze the variation of the portal vein(PV) trunk and branches and evaluate the value of CT virtual endoscopy(CTVE) in accurately distinguishing the variation type of PV using MSCT post-processing techniques.[Methods] All patients underwent upper abdomen enhancement scanning using 64 slice spiral CT in the institute. Five hundreds patients who have good PV phase images were involved. VR,MIP were used for the reconstruction of PV grade 1-3 branches and analyzing the anatomy and variation of PV. For the types of variations which were difficult to distinguish on VR and MIP images,such as short common trunk or trifurcation of the main PV(MPV),and a short RAPV-LPV trunk or a short RAPV-RPPV trunk were easily considered as trifurcation, we could use CTVE to analyze the lumen structure at the point of trifurcation to rectify the conventional observing technique.[Results] According to the concept proposed by Couinaud,using conventional observing techniques and CTVE, there were 173 cases which have variations of PV in 500 patients in PV imaging, in which the MPV had five types of variations in all 67 cases and seven types in 105 cases of RPV,one type of variation of LPV.[Conclusions] There were high rate of intrahepatic PV variation and many mutation types. So analyzing acutly the types and proportion of variation of PV has great value to liver anatomy and significance to liver surgery.Especially, in the analysis of PV variation,CTVE could clearly distinguish trifurcation with a short common trunk,which can be used for PV anatomy, correcting deficiencies of the original methods to obtain more accurate data.