Diagnostic accuracy and radiation dose of DECT protocol for follow-up imaging of EVAR compared to the standard triphasic protocol: a literature review

Introduction: Contrast-enhanced CT is good standard for the detection and classification of endoleaks for the surveillance of patients who have undergone endovascular aneurysm repair (EVAR).1 Although the triphasic protocol is efficient, after EVAR, patients are required to attend indefinite follow-up and are exposed to substantial accumulative radiation dose and hence, increased lifelong risk of developing cancer.2Objectives: This review aims to evaluate diagnostic performance of dual-energy CT (DECT) in follow-up examinations after EVAR and its radiation dose estimates compared to the standard triphasic protocol.Methods: A systematic search was conducted on the following databases: MEDLINE, PubMed, and Scopus. Articles were screened against the inclusion and exclusion criteria. A narrative review was performed. A summary statistic table of the calculated mean effective dose, percentages in dose reduction and diagnostic performance of DECT were pooled. Results: Five original articles were included. Compared to the triphasic protocol being the reference standard, data from the DECT acquisitions were observed to have 98–100% overall accuracy for the detection of type I and II endoleaks. The cumulative effective doses were significantly different (P < 0.001) between the protocols. The effective dose delivered in the DECT protocol was approximately 61% lower than that delivered to the patient by the standard triphasic protocol (11.1 mSv compared with 27.8 mSv).Conclusion: DECT protocol can replace the standard triphasic protocol in follow-up imaging after EVAR for the detection of type I and II endoleaks. This acquisition protocol also significantly reduces the effective dose to the patients.