Effectiveness of single-energy metal artifact reduction algorithm in CT: application to contrast-enhanced CT with EVAR and coil embolization.

This study aimed to evaluate the efficacy of the single-energy metal artifact reduction (SEMAR) algorithm in reducing metal artifacts and enhancing image quality in contrast-enhanced computed tomography (CT) for patients undergoing endovascular aneurysm repair (EVAR) with coil embolization. Thirty-eight patients (mean age 81.0 ± 6 years; 31 men, 7 women) who underwent contrast-enhanced CT following EVAR and internal iliac artery coil embolization between September 2022 and May 2023 were retrospectively analyzed. The Artifact Index (AI) quantified metallic artifacts from internal iliac artery aneurysm coils in CT images, calculated from the standard deviation of the artifact-containing region relative to a reference region. CT values of the external iliac artery at the same slice were also evaluated and compared. Two radiologists independently performed qualitative assessments of SEMAR and non-SEMAR images. SEMAR significantly reduced metal artifacts, decreasing the AI from 171.9 ± 74.5 HU to 35.8 ± 16.9 HU (p < 0.001). The mean CT values of the external iliac artery were similar for SEMAR (259.4 ± 63.7 HU) and non-SEMAR (257.1 ± 63.6 HU, indicating no significant difference. Qualitative assessment scores improved significantly with SEMAR (from 1.0 ± 0.0 to 2.5 ± 0.5; p < 0.001), enhancing visualization of internal iliac artery aneurysms. Interobserver agreement was high (κ = 0.83). The SEMAR algorithm effectively reduces metal artifacts in contrast-enhanced CT, significantly enhancing image quality without altering adjacent artery CT values. These improvements enhance the image quality of post-operative assessments in patients undergoing EVAR with coil embolization.
Competing Interests: Declarations. Ethical approval: This study was conducted in accordance with the principles of the Declaration of Helsinki. Ethical approval was obtained from the Ethics Committee of Jichi Medical University Saitama Medical Center (S23-080). Consent to publish: An opt-out policy has been implemented. The opt-out document is available on the Department of Radiology’s website at the Saitama Medical Center, Jichi Medical University, and at the laboratory reception. All participants have been provided the opportunity to decline inclusion in this research. Competing interests: Financial interests: Junji Mochizuki, Osamu Manabe and Noriko Oyama-Manabe have received research funding from Canon Medical Systems. The other authors have no financial or non-financial interests to disclose.
(© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)