Portal vein segmentation of a 3D-planning system for liver surgery--in vivo evaluation in a porcine model.
BACKGROUND
Computer systems allow the planning of complex liver operations. The segmentation of intrahepatic vessels builds the basis for the calculation of liver segments and resection proposals. For surgical use, it is essential to know the capabilities and limitations of the segmentation. The aim of this study was to determine the sensitivity and precision of the portal vein segmentation of a computer planning system for liver surgery in vivo.


METHODS
Segmentations were performed with the software system HepaVision on computed tomography (CT) scan data of domestic pigs. An in situ corrosion cast of the portal vein served as the gold standard. The segmentation results of the portal vein and the corrosion cast were compared with regard to sensitivity, precision, and amount of short-circuit segmentations.


RESULTS
The methodology demonstrated high resolution ex situ. The in vivo sensitivity of the portal vein segmentation was 100% for vessels of more than 5 mm in diameter and 82% for vessels of 3-4 mm. All segment branches were detected as well as 84% of the first subsegment branches with a diameter of more than 3 mm. The precision of the system was 100% for segment branches and 89% for the first subsegment vessels. The amount of internal short-circuit segmentations was less than 3.0%. No external short-circuits were found.


CONCLUSIONS
The system has a high precision and sensitivity under clinical conditions. The segmentation is suitable for portal vein branches of the first and second order and for vessels of >/=3 mm in diameter.
Lehmann
Kai S
KS
Department of General, Vascular and Thoracic Surgery-Chirurgische Klinik I, Charité-Campus Benjamin Franklin, Freie- und Humboldt-Universität zu Berlin, Hindenburgdamm 30, 12200, Berlin, Germany. kai.lehmann@charite.de
Ritz
Joerg-P
JP
Valdeig
Steffi
S
Schenk
Andrea
A
Holmer
Christoph
C
Peitgen
Heinz-O
HO
Buhr
Heinz-J
HJ
Frericks
Bernd B
BB
D000818:Animals; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D008099:Liver / Q000033:anatomy & histology* / Q000601:surgery; D023421:Models, Animal; D011169:Portal Vein / Q000033:anatomy & histology*; D012680:Sensitivity and Specificity; D013552:Swine; D014057:Tomography, X-Ray Computed