National Institutes of Health Clinical Center, Bethesda, MD 20892-1182, USA.
Med Phys. 2012 Feb;39(2):964-75. doi: 10.1118/1.3679013.
Computed tomographic colonography (CTC) is a minimally invasive technique for colonic polyps and cancer screening. Teniae coli are three bands of longitudinal smooth muscle on the colon surface. Teniae coli are important anatomically meaningful landmarks on human colon. In this paper, the authors propose an automatic teniae coli detection method for CT colonography.
The original CTC slices are first segmented and reconstructed to a 3D colon surface. Then, the 3D colon surface is unfolded using a reversible projection technique. After that the unfolded colon is projected to a 2D height map. The teniae coli are detected using the height map and then reversely projected back to the 3D colon. Since teniae are located at the junctions where the haustral folds meet, the authors apply 2D Gabor filter banks to extract features of haustral folds. The maximum response of the filter banks is then selected as the feature image. The fold centers are then identified based on local maxima and thresholding on the feature image. Connecting the fold centers yields a path of the folds. Teniae coli are extracted as lines running between the fold paths. The authors used the spatial relationship between ileocecal valve (ICV) and teniae mesocolica (TM) to identify the TM, then the teniae omentalis (TO) and the teniae libera (TL) can be identified subsequently.
The authors tested the proposed method on 47 cases of 37 patients, 10 of the patients with both supine and prone CT scans. The proposed method yielded performance with an average normalized root mean square error (RMSE) ( ± standard deviation [95% confidence interval]) of 4.87% ( ± 2.93%, [4.05% 5.69%]).
The proposed fully-automated teniae coli detection and identification method is accurate and promising for future clinical applications.
计算机断层结肠成像(CTC)是一种用于结肠息肉和癌症筛查的微创技术。结肠带是结肠表面的三条纵向平滑肌带。结肠带在人体结肠上是重要的解剖学意义上的标志。在本文中,作者提出了一种用于 CT 结肠成像的自动结肠带检测方法。
首先对原始 CTC 切片进行分割和重建为 3D 结肠表面。然后,使用可逆投影技术展开 3D 结肠表面。之后,将展开的结肠投影到 2D 高度图上。使用高度图检测结肠带,然后将其反向投影回 3D 结肠。由于结肠带位于皱襞相遇的交界处,作者应用二维 Gabor 滤波器组提取皱襞的特征。然后选择滤波器组的最大响应作为特征图像。基于特征图像上的局部最大值和阈值确定褶皱中心。连接褶皱中心得到褶皱的路径。提取位于褶皱路径之间的结肠带作为线。作者使用回盲瓣(ICV)和结肠系膜结肠带(TM)之间的空间关系来识别 TM,然后可以识别结肠带网膜(TO)和结肠带游离(TL)。
作者在 37 名患者的 47 例中测试了所提出的方法,其中 10 例患者进行了仰卧位和俯卧位 CT 扫描。所提出的方法的性能平均归一化均方根误差(RMSE)( ± 标准差 [95%置信区间])为 4.87%( ± 2.93%,[4.05%5.69%])。
所提出的全自动结肠带检测和识别方法准确,有希望在未来的临床应用中得到应用。