Abstract
This study aimed to establish the local diagnostic reference levels (LDRLs) of computed tomography pulmonary angiography (CTPA) examinations based on body size with regard to noise magnitude as a quality indicator. The records of 127 patients (55 males and 72 females) who had undergone CTPAs using a 128-slice CT scanner were retrieved. The dose information, scanning acquisition parameters, and patient demographics were recorded in standardized forms. The body size of patients was categorized into three groups based on their anteroposterior body length: P1 (14–19 cm), P2 (19–24 cm), and P3 (24–31 cm), and the radiation dose exposure was statistically compared. The image noise was determined quantitatively by measuring the standard deviation of the region of interest (ROI) at five different arteries—the ascending and descending aorta, pulmonary trunk, and the left and right main pulmonary arteries. We observed that the LDRL values were significantly different between body sizes (p < 0.05), and the median values of the CT dose index volume (CTDIvol) for P1, P2, and P3 were 6.13, 8.3, and 21.40 mGy, respectively. It was noted that the noise reference values were 23.78, 24.26, and 23.97 HU for P1, P2, and P3, respectively, which were not significantly different from each other (p > 0.05). The CTDIvol of 9 mGy and dose length product (DLP) of 329 mGy∙cm in this study were lower than those reported by other studies conducted elsewhere. This study successfully established the LDRLs of a local healthcare institution with the inclusion of the noise magnitude, which is comparable with other established references.
Highlights
Computed tomography (CT) has become a necessity in clinical practice to gain beneficial information on diseases and aid the diagnosis of patients
Several studies have reported that the data acquisition settings, detector configuration, machine quality assurance, patient characteristics, post-processing technique and operator’s skill are factors that expose patients to high doses of radiation in CT examinations [2,3,4,5]
This study was based on the recommendations of International Commission on Radiological Protection (ICRP) Publication 135, where at least 30 subjects were required for establishing a diagnostic reference level (DRL) in a specific patient group [17]
Summary
Computed tomography (CT) has become a necessity in clinical practice to gain beneficial information on diseases and aid the diagnosis of patients. Patients might suffer the side effects of being exposed to a significantly high radiation dose that increases the risk of developing cancer [1]. Several studies have reported that the data acquisition settings, detector configuration, machine quality assurance, patient characteristics, post-processing technique and operator’s skill are factors that expose patients to high doses of radiation in CT examinations [2,3,4,5]. With diverse factors affecting radiation dose exposure, several optimization techniques have been introduced to protect patients [6,7,8,9]. The optimization processes must still produce quality images, which are crucial to ensure that clinicians can reach an accurate diagnosis for patients and plan an effective treatment regime. Christianson et al introduced an automated technique for estimating the noise level of CT images to facilitate the further improvement of CT protocols [10]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
