Analysis of CT radiation dose based on radiation-dose-structured reports

Abstract

Objective To analyse the CT radiation dose statistically using the standardized radiation-dose-structured report （RDSR） of digital imaging and communications in medicine （DICOM）. Methods Using the self-designed software, 1230 RDSR files about CT examination were obtained searching on the picture archiving and communication system （ PACS ） . The patient dose database was established by combination of the extracted relevant information with the scanned sites. The patients were divided into adult group （over 10 years） and child groups （0-1 year, 1-5 years, 5-10 years） according to the age. The average volume CT dose index （ CTDIvol ） and dose length product （ DLP） of all scans were recorded respectively, and then the effective dose （ E） was estimated. The DLP value at 75% quantile was calculated and compared with the diagnostic reference level （ DRL） . Results In adult group, CTDIvol and DLP values were moderately and positively correlated （ r=0.41 ） , the highest E was observed in upper abdominal enhanced scan, and the DLP value at 75% quantile was 60% higher than DRL. In child group, their CTDIvol in group of 5-10 years was greater than that in groups of 0-1 and 1-5 years （ t=2.42, 2.04, P〈0.05）;the DLP value was slightly and positively correlated with the age （r=0.16）, while E was moderately and negatively correlated with the age （ r = -0.48 ） . Conclusions It is a simple and efficient method to use RDSR to obtain the radiation doses of patients. With the popularization of the new equipment and the application of regionalized medical platform, RDSR would become the main tool for the dosimetric level surveying and individual dose recording. Key words: Structured report; Radiation dose; Computed tomography; Diagnostic reference level