Cardiovascular ImagingComputed Tomography Angiography Combined With Knowledge-Based Iterative Algorithm for Transcatheter Aortic Valve Implantation Planning: Image Quality and Radiation Dose Exposure With Low-kV and Low-Contrast-Medium ProtocolIppolito, Davide MD∗,†; Riva, Luca MD∗,†; Talei Franzesi, Cammillo MD∗,†; De Vito, Andrea MD∗,†; Cangiotti, Cecilia MD∗,†; Crespi, Andrea PhD‡; Corso, Rocco MD∗; Sironi, Sandro MD∗,§ Author Information From the ∗Department of Diagnostic Radiology, “San Gerardo” Hospital †School of Medicine, University of Milano-Bicocca ‡Department of Medical Physics, “San Gerardo” Hospital, Monza §Department of Diagnostic Radiology, H Papa Giovanni XIII, Bergamo, Italy. Received for publication March 22, 2019; accepted July 8, 2019. Correspondence to: Ippolito Davide, MD, Department of Diagnostic Radiology, University of Milano-Bicocca, H. S. Gerardo, Via Pergolesi 33, 20900 Monza, Italy (e-mail: [email protected]). This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. The authors declare no conflict of interest. Journal of Computer Assisted Tomography: 1/2 2020 - Volume 44 - Issue 1 - p 13-19 doi: 10.1097/RCT.0000000000000965 Buy Metrics Abstract Objective To evaluate image quality and radiation dose exposure of low-kV setting and low-volume contrast medium (CM) computed tomography angiography (CTA) protocol for transcatheter aortic valve implantation (TAVI) planning in comparison with standard CTA protocol. Methods Sixty-patients were examined with 256-row MDCT for TAVI planning: 32 patients (study group) were evaluated using 80-kV electrocardiogram-gated protocol with 60 mL of CM and IMR reconstruction; 28 patients underwent a standard electrocardiogram-gated CTA study (100 kV; 80 mL of CM; iDose4 reconstruction). Subjective and objective image quality was evaluated in each patient at different aortic levels. Finally, we collected radiation dose exposure data (CT dose index and dose-length product) of both groups. Results In study protocol, significant higher mean attenuation values were achieved in all measurements compared with the standard protocol. There were no significant differences in the subjective image quality evaluation in both groups. Mean dose-length product of study group was 56% lower than in the control one (P < 0.0001). Conclusion Low-kV and low-CM volume CTA, combined with IMR, allows to correctly performing TAVI planning with high-quality images and significant radiation dose reduction compared with standard CTA protocol. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.