Chunhapongpipat Krisorn, Boonklurb Ratinan, Chaopathomkul Bundit, Sirisup Sirod, Lipikorn Rajalida
Machine Intelligence and Multimedia Information Technology laboratory (MIMIT Lab), Department of Mathematics and Computer Science, Faculty of Science, Chulalongkorn University, Payathai Road, Bangkok, 10330, Thailand.
Department of Mathematics and Computer Science, Faculty of Science, Chulalongkorn University, Payathai Road, Bangkok, 10330, Thailand.
BMC Med Imaging. 2017 Sep 4;17(1):53. doi: 10.1186/s12880-017-0224-6.
In computed tomography colonography images, electronic cleansing (EC) is applied to remove opacified residual materials, called fecal-tagging materials (FTM), using positive-contrast tagging agents and laxative to facilitate polyp detection.
The proposed EC, EC , integrates the gradient directional second derivative into material fraction model to preserve submerged soft tissue (ST) under FTM. Three-material fraction model is used to remove FTM and artifacts at air-tagging (AT) layers and T-junctions where air, ST, and FTM material meet simultaneously. Moreover, the proposed AT layer identification is used to distinguish AT layers from air-tissue-tagging (ATT) layers in order to preserve ATT layers during cleansing. The clinical evaluation on 467 3-Dimensional band view images was conducted by the abdominal radiologist using four grading levels of cleansing quality with five causes of low quality EC. The amount of the remaining artifacts at T-junctions was approximated from the results of EC . The results from EC were compared with the results from syngo.via Client 3.0 Software, EC , and the fast three-material modeling, EC , using the preference of the radiologist. Two-tailed paired Wilcoxon signed rank test is used to indicate statistical significance.
The average grade on cleansing quality is 2.89 out of 4. The artifacts at T-junctions from 86.94% of the test images can be removed, whereas artifacts at T-junctions from only 13.06% of the test images cannot be removed. For 13.06% of the test images, the results from EC are more preferable to the results from EC (p<0.008). For all the test images, the results from EC are more preferable to the results from EC (p<0.001). Finally, the visual assessment shows that EC can preserve ATT layers, submerged polyps and folds while EC can preserve only submerged folds but fails to preserve ATT layers.
From our implementation, EC can improve the performance of the existing EC, such that it can preserve ST, especially ATT layers and remove the artifacts at T-junctions which have never been proposed by any other methods before.
在计算机断层结肠成像图像中，电子清洗（EC）应用阳性对比标记剂和泻药来清除不透明的残留物质，即粪便标记物（FTM），以促进息肉检测。
所提出的EC，即EC ，将梯度方向二阶导数整合到物质分数模型中，以保留FTM下的淹没软组织（ST）。使用三物质分数模型去除空气标记（AT）层和空气、ST和FTM物质同时相遇的T形交界处的FTM和伪影。此外，所提出的AT层识别用于区分AT层和空气组织标记（ATT）层，以便在清洗过程中保留ATT层。腹部放射科医生对467幅三维带状视图图像进行了临床评估，使用四个清洗质量等级和五个低质量EC的原因。T形交界处剩余伪影的数量根据EC 的结果进行估算。使用放射科医生的偏好将EC 的结果与syngo.via Client 3.0软件、EC 和快速三物质建模EC 的结果进行比较。使用双尾配对Wilcoxon符号秩检验来表明统计学意义。
清洗质量的平均等级为4分中的2.89分。86.94%的测试图像中T形交界处的伪影可以被去除，而只有13.06%的测试图像中T形交界处的伪影无法被去除。对于13.06%的测试图像，EC 的结果比EC 的结果更可取（p<0.008）。对于所有测试图像，EC 的结果比EC 的结果更可取（p<0.001）。最后，视觉评估表明，EC 可以保留ATT层、淹没的息肉和褶皱，而EC 只能保留淹没的褶皱，但无法保留ATT层。
从我们的实现来看，EC 可以提高现有EC的性能，使其能够保留ST，特别是ATT层，并去除T形交界处的伪影，这是之前任何其他方法都未曾提出过的。
