THREE-DIMENSIONAL PANORAMA IMAGE OF TUBULAR STRUCTURE USING STEREO ENDOSCOPY

摘要

The narrow viewing angle of endoscopes impedes obtaining complete images of the digestive tract. In this article, we propose a method to acquire 3D panorama images of the digestive tract using stereo endoscopy. The method consists of acquiring sequential images of the digestive tract by moving the endoscope, reconstructing 3D surfaces for each image by stereo techniques, estimating the endoscope position using scene flow, and reconstructing a 3D image of the digestive tract by merging the surfaces. We verified the method using cylindrical pipes and a pig esophagus covered with printed squares with sides of 10 mm. The estimation error of the endoscope position was within 3% after moving 80 mm. In addition, we mapped the panorama image into a planar image to evaluate the method outcomes. The panorama procedure reduced the number of missing points owing to stereo matching failure or deficiency of resolution and improved the quality of the image. The estimation error of the sides of the reconstructed square was within 2%. The proposed method might be suitable to obtain an expanded view of the digestive tract from stereo endoscopy. This method has the potential to map and quantify the pathologic lesions of the digestive tract.