Abstract / Summary
Abstract Computed tomography (CT) plays an important role in diagnosing diseases affecting the head, thorax, abdomen, and other body regions. However, the increasing use of CT has also raiseds concerns regarding radiation exposure to patients. Dual-energy CT (DECT) is a newer imaging technique developed to improve image quality and tissue characterization while maintaining or reducing radiation dose when compared with conventional single-energy CT (SECT). This review aimed to compare radiation dose differences between SECT and DECT in different anatomical regions. This systematic review was carried out according to the PRISMA 2020 guidelines and registered in PROSPERO (CRD420251180971). A detailed literature search was performed in PubMed, Scopus, Web of Science, Google Scholar, and ResearchGate for studies published between 2020 and 2025. A total of 7,819 records were identified. After screening and eligibility assessment, 22 studies were included in the qualitative review, while 8 studies were selected for meta-analysis. Data related to sample size, mean radiation dose, and standard deviation for both SECT and DECT were extracted from studies involving head, thorax, abdomen, head and neck, and thorax/abdomen/pelvis imaging. The included studies showed varying radiation dose patterns between SECT and DECT depending on the body region examined. Most abdominal studies reported lower radiation dose values with DECT compared with SECT. In contrast, studies involving the thorax and head regions showed either similar or slightly higher dose values with DECT. The pooled analysis indicated an overall modest reduction in radiation dose with DECT compared to SECT (standardized mean difference = –0.39; 95% confidence interval: –0.62 to –0.16; p < 0.05). Improvements in dose efficiency were mainly associated with advanced dual-source systems, tube current modulation, and iterative reconstruction techniques. The findings suggest that modern DECT systems can provide radiation doses comparable to or lower than those of SECT, especially in abdominal imaging. Although some studies reported slightly higher doses in thoracic and neuroimaging examinations, DECT offers additional diagnostic benefits through improved image quality and material differentiation. Therefore, DECT may be considered a valuable and dose-conscious imaging technique that supports the ALARA (As Low As Reasonably Achievable) principle in clinical practice.