Position of the diaphragm influenced by the filling degree of the abdominal and pelvic cavity
10.3760/cma.j.cn112271-20230508-00137
- VernacularTitle:腹盆腔充盈度对膈肌位置的影响
- Author:
Wei SONG
1
;
Qingshan LI
;
Tianxiao FU
Author Information
1. 苏州大学附属第一医院肿瘤放疗科，苏州 215006
- Keywords:
Abdominal and pelvic cavity;
Filling degree;
Influence;
Diaphragm
- From:
Chinese Journal of Radiological Medicine and Protection
2023;43(11):888-892
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To explore the affects of the filling degree of the abdominal and pelvic cavity to the position of the diaphragm.Methods:The computed tomography (CT) images of 25 patients from 137 CT scans stored in the Picture Archiving and Communication System of the First Affiliated Hospital of Soochow University from March 2018 to September 2020 were reviewed and analyzed retrospectively. Every patient was scanned 4-7 times. The outline of the abdominal and pelvic cavity from the diaphragmatic dome to the superior margin of pubic symphysis was drawn at every cross section, and then the filling volumes of the abdominal and pelvic cavities and the overall filling volume were calculated. For the same patient within 4-7 CT scans, per pair of different images was compared randomly and 379 comparison pairs were obtained. The volume change rate (△ VR) of the abdominal and pelvic cavity and the height difference (△ H) of the diaphragmatic dome were calculated. The images with "larger overall filling volume of the abdominal and pelvic cavity and higher diaphragmatic dome" were defined as consistent group, and those with "larger overall filling volume and lower diaphragmatic dome" were defined as inconsistent group. The percentage of images in the consistent group in all samples and the percentage of images showing deep inspiration in the inconsistent group in all samples were calculated. △ VR and △ H were compared between the consistent and inconsistent groups. △ VR of the abdomen and pelvic cavities in the consistent group was compared using the Mann-Whitney test. The correlations between △ VR of the abdomen and pelvic cavities and the elevation of the diaphragmatic dome in the consistent group were analyzed using Spearman correlation analysis. The average elevation of the diaphragmatic dome in all samples and the consistent group was simulated if the filling volume of the abdomen and pelvic cavity was increased by 500 ml. Results:The percentage of images in the consistent group in all samples was 67.28%. The percentage of images showing deep inspiration in the inconsistent group in all samples was 26.39%. There were significant differences in △ VR and △ H of the abdomen and pelvic cavity between the consistent and inconsistent groups ( Z=-4.95, -5.49, P<0.05). In the consistent group, there were significant differences in △ VR between the abdominal cavity and pelvic cavity ( Z=-7.53, P<0.05), and the elevation of the diaphragmatic dome was correlated with the △ VR of the abdominal cavity ( rs=0.43, P<0.05). The simulated calculation showed that an average increase of 500 ml in the filling volume of the abdominal and pelvic cavity result ed in an average elevation of 4.54 and 8.43 mm in the diaphragmatic dome in all samples and the consistent group, respectively. Conclusions:The filling degree of the abdominal and pelvic cavity may be one of the main factors affecting the position of the diaphragm and the precision of radiotherapy for relevant organs near the diaphragm, especially the filling degree of the abdominal cavity. It is recommended to repeat the filling degree of the abdominal and pelvic cavity by CT localization scanning as much as possible during radiotherapy.
