Diploma project, Winter 2000
Prof. Reymond Clavel
Ass. Gaëtan Marti, Dr. Charles Baur
3D reconstruction of the bile ducts
by Patrick Ramer
Lausanne, February 2001
|The goal of the project
This project aims to provide a new tool for endoscopic surgery, particularly for interventions concerning the liver and the pancreas. In the case of partial excision of liver segments, not only the surface and the tissue of the organ have to be considered, but also the distribution of the vessels (arteries and veins) and the bile ducts in the liver. The bile duct system is reconstructed in 3D from two 2D X-ray images acquired with per-operative cholangiography. This 3D model of the ducts can then be superimposed on the endoscopic image in real-time. This will allow to “see through” the liver and to locate the bile ducts directly on the endoscopic image.
The entire process consists of three steps:
1. Image acquisition and feature extraction
Feature extraction is manual and is
both projection images separately. Several propositions are made for an
Several criteria are presented to exclude
from the final solution. The concept of epipolar geometry plays an
role at this stage and is also used for back-projection of matched
to construct the 3D model. The two images are matched using a recursive
scheme adapted for tree-like structures.
Surgical applications include partial hepatectomy in the case of cancer, metastasis and malformation or for transplantation; further the treatment of echinococcosis and chronic pancreatitis.