High-pitch low-voltage CT coronary artery calcium scoring with tin
filtration: accuracy and radiation dose reduction
Moritz H. Albrecht
U. Joseph Schoepf
Taylor M. Duguay
Carlo N. De Cecco
John W. Nance
Domenico De Santis
Marwen H. Eid
Chelsea D. Eason
Zachary M. Thompson
Maximilian J. Bauer
Brian E. Jacobs
Received: 8 November 2017 /Revised: 4 December 2017 /Accepted: 6 December 2017 /Published online: 5 February 2018
European Society of Radiology 2018
Objectives To investigate diagnostic accuracy and radiation dose of high-pitch CT coronary artery calcium scoring (CACS) with
tin filtration (Sn100kVp) versus standard 120kVp high-pitch acquisition.
Methods 78 patients (58% male, 61.5±9.1 years) were prospectively enrolled. Subjects underwent clinical 120kVp high-pitch
CACS using third-generation dual-source CT followed by additional high-pitch Sn100kVp acquisition. Agatston scores, calcium
volume scores, Agatston score categories, percentile-based risk categorization and radiation metrics were compared.
Results 61/78 patients showed coronary calcifications. Median Agatston scores were 34.9 [0.7–197.1] and 41.7 [0.7–207.2] and calcium
volume scores were 34.1 [0.7–218.0] for Sn100kVp and 35.7 [1.1–221.0] for 120kVp acquisitions, respectively (both p<0.0001). Bland-
Altman analysis revealed underestimated Agatston scores and calcium volume scores with Sn100kVp versus 120kVp acquisitions (mean
difference: 16.4 and 11.5). However, Agatston score categories and percentile-based risk categories showed excellent agreement (ĸ=0.98
and ĸ=0.99). Image noise was 25.8±4.4HU and 16.6±2.9HU in Sn100kVp and 120kVp scans, respectively (p<0.0001). Dose-length-
product was 9.9±4.8mGy*cm and 40.9±14.4mGy*cm with Sn100kVp and 120kVp scans, respectively (p<0.0001). This resulted in
significant effective radiation dose reduction (0.13±0.07mSv vs. 0.57±0.2mSv, p<0.0001) for Sn100kVp acquisitions.
Conclusion CACS using high-pitch low-voltage tin-filtered acquisitions demonstrates excellent agreement in Agatston score and
percentile-based cardiac risk categorization with standard 120kVp high-pitch acquisitions. Furthermore, radiation dose was
significantly reduced by 78% while maintaining accurate risk prediction.
• Coronary artery calcium scoring with tin filtration reduces radiation dose by 78%.
• There is excellent correlation between high-pitch Sn100kVp and standard 120kVp acquisitions.
• Excellent agreement regarding Agatston score categories and percentile-based risk categorization was achieved.
• No cardiac risk reclassifications were observed using Sn100kVp coronary artery calcium scoring.
Keywords Computed tomography
Coronary artery calcium
* U. Joseph Schoepf
Division of Cardiovascular Imaging, Department of Radiology and
Radiological Science, Medical University of South Carolina,
Charleston, SC, USA
Division of Paediatric Radiology, Department of Radiology, Medical
University of Graz, Graz, Austria
Department of Diagnostic and Interventional Radiology, University
Hospital Frankfurt, Frankfurt, Germany
Division of Cardiology, Medical University of South Carolina,
Charleston, SC, USA
Heart and Vascular Center, Medical University of South Carolina,
Ashley River Tower, 25 Courtenay Drive,
Charleston, SC 29425-2260, USA
Department of Radiological Sciences, Oncology and Pathology,
University of Rome BSapienza^, Rome, Italy
Department of Biomedical Imaging and Image-guided Therapy,
Medical University of Vienna, Vienna, Austria
Department of Cardiology and Intensive Care Medicine, Heart Center
Munich-Bogenhausen, Munich, Germany
European Radiology (2018) 28:3097–3104