1. a. Department of Medical Equipment|b. Radiation Therapy Center, Nanjing First Hospital, Nanjing Medical University, Nanjing Jiangsu 210006, China；2. Center of Medical Physics with Nanjing Medical University, Nanjing Jiangsu 210029, China|3. Nanjing
Emergency Medical Center, Nanjing Jiangsu 210003, China
Abstract：Objective To test and quantitatively analyze the geometric accuracy and related influencing factors of the bladder structure automatically drawn by rtStation, a software of DaTu Medical Technology Co., Ltd, in CT images of rectal cancer patients, and to provide data reference for clinical application and optimization of the automatic delineation software. Methods A total of 30 cases of rectal cancer patients treated in Nanjing First Hospital, Nanjing Medical University, from March 2017 to October 2019 were analyzed retrospectively based on the index including the differences in volume (ΔV%), dice similarity coefficient (DSC), Deviation of Centroid (DC). Quantitative evaluation software was used to automatically draw and clinically confirm the differences in the shape,
volume, position and other aspects of the organ contour, and SPSS was used for statistical analysis. Results In the 30 cases (16 cases in supine position|14 cases in prone position), DSC of the two sketching methods was significantly correlated with bladder filling
volume. Besides 3 cases with insufficient bladder filling, for the remaining 27 cases, their DSC, ΔV% and DC were 0.89±0.05, (-4.44±16.25) % and (0.22±0.17) cm. The position difference in x, y and z directions was (0.08±0.11) cm, (0.25±0.62) cm and (0.26±0.58) cm. The automatic delineation time of 30 bladder structures was (47.3±6.8) s. Conclusion Using rtStation automatic delineation tool, the bladder structure with good filling can be automatically delineated in the positioning CT image, and the accuracy
of delineation in both scanning positions is close to the level of manual delineation, indicating that the tool has good robustness robustness to the varieties of body position, but it has certain limitations for the bladder structure with insufficient filling.
