Body physical parameters instead of water equivalent diameter to calculate size-specific dose estimate in adult chest CT

• Published in: Scientific reports Vol. 14; no. 1; pp. 17053 - 8
• Main Authors: Hu, Xiaoyan, Gou, Jie, Yang, Fan, Guo, Dajing
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 24.07.2024; Nature Publishing Group; Nature Portfolio
• Subjects: 692/308; 692/700; Adult; Aged; Aged, 80 and over; BMI; Body Mass Index; Body size; Body Weight; Chest; Computed tomography; Female; Humanities and Social Sciences; Humans; Male; Middle Aged; multidisciplinary; Radiation Dosage; Radiography, Thoracic - methods; Retrospective Studies; Science; Science (multidisciplinary); Size-specific dose estimate; Thorax - diagnostic imaging; Tomography, X-Ray Computed - methods; Volume computed tomography dose index; Water; Water equivalent diameter; Weight; Volume computed tomography dose index; Size-specific dose estimate; Water equivalent diameter; Weight; BMI
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-024-66657-y

This study aimed to investigate body physical parameters as substitutes for water equivalent diameter (Dw) while calculating size-specific dose estimates (SSDEs) during adult chest computed tomography (CT). A retrospective analysis was conducted on 776 patients. Patients were divided into training set (542 patients) and validation set (234 patients) according to a ratio of 7:3. The correlations between physical parameters and Dw were analyzed. The differences between SSDE substitutes and the reference SSDE (SSDE reference ) were compared. Strong positive correlations were observed between body mass index (BMI) and Dw as well as between weight and Dw in overall, male, and female patients (all p  < 0.001). The correlations between BMI and Dw were stronger than those between weight and Dw in overall, male, and female subjects (all p  < 0.001). SSDE weight and SSDE BMI were not significantly different from SSDE reference ( p  > 0.05). The RMSEs of overall patients between SSDE weight and SSDE reference as well as between SSDE BMI and SSDE reference were 0.237 and 0.2, respectively. The use of sex-specific regression equations for BMI caused a slightly reduction in RMSE. Weight and BMI can be used as surrogate parameters for Dw when calculating SSDE in adult chest CT exams, with BMI being the preferred substitute parameter.