A real-time endoscope tip motion tracker

In endoscopy, the position and orientation of the endoscope’s distal tip are important for locating lesions. Currently, position is estimated using scale lines on the endoscope’s surface and orientation is estimated based on the position of the proximal handle. Both these estimates are inaccurate and cannot be continuously recorded. Real-time endoscope motion tracking should improve tumor localization during colonoscopy. We developed an endoscope tracker that uses a pair of trackballs and two video cameras. It can track real-time changes in insertion length and rotation during an endoscopic procedure. A prototype device has been built and its performance has been evaluated.