title: Feasibility of spectral shaping for detection and quantification of coronary calcifications in ultra-low dose CT.
abstract: OBJECTIVE
  To evaluate detectability and quantification of coronary calcifications for CT with a tin filter for spectral shaping.
  
  
  METHODS
  Phantom inserts with 100 small and 9 large calcifications, and a moving artificial artery with 3 calcifications (speed 0-30 mm/s) were placed in a thorax phantom simulating different patient sizes. The phantom was scanned in high-pitch spiral mode at 100 kVp with tin filter (Sn100 kVp), and at a reference of 120 kVp, with electrocardiographic (ECG) gating. Detectability and quantification of calcifications were analyzed for standard (130 HU) and adapted thresholds.
  
  
  RESULTS
  Sn100 kVp yielded lower detectability of calcifications (9 % versus 12 %, p = 0.027) and lower Agatston scores (p < 0.008), irrespective of calcification, patient size and speed. Volume scores of the moving calcifications for Sn100 kVp at speed 10-30 mm/s were lower (p < 0.001), while mass scores were similar (p = 0.131). For Sn100 kVp with adapted threshold of 117 HU, detectability (p = 1.000) and Agatston score (p > 0.206) were similar to 120 kVp. Spectral shaping resulted in median dose reduction of 62.3 % (range 59.0-73.4 %).
  
  
  CONCLUSIONS
  Coronary calcium scanning with spectral shaping yields lower detectability of calcifications and lower Agatston scores compared to 120 kVp scanning, for which a HU threshold correction should be developed.
  
  
  CONCLUSIONS
  • Sn100kVp yields lower detectability and lower Agatston scores compared to 120kVp • Adapted HU threshold for Sn100kVp provides Agatston scores comparable to 120kVp • Sn100 kVp considerably reduces dose in calcium scoring versus 120 kVp.
authors: Department of Radiology, University of Groningen, University Medical Center Groningen, Hanzeplein 1, EB44, 9713 GZ, Groningen, The Netherlands.|Center for Medical Imaging North-East Netherlands (CMI-NEN), University of Groningen, University Medical Center Groningen, Hanzeplein 1, Groningen, The Netherlands.
authors: Marleen
authors: M
authors: Vonder
authors: Department of Radiology, University of Groningen, University Medical Center Groningen, Hanzeplein 1, EB44, 9713 GZ, Groningen, The Netherlands.|Center for Medical Imaging North-East Netherlands (CMI-NEN), University of Groningen, University Medical Center Groningen, Hanzeplein 1, Groningen, The Netherlands.
authors: Gert Jan
authors: GJ
authors: Pelgrim
authors: Department of Radiology, University of Groningen, University Medical Center Groningen, Hanzeplein 1, EB44, 9713 GZ, Groningen, The Netherlands.
authors: Sèvrin E M
authors: SE
authors: Huijsse
authors: Institute of Clinical Radiology and Nuclear Medicine, Medical Faculty Mannheim, University Medical Center Mannheim, Heidelberg University, Heidelberg, Germany.
authors: Mathias
authors: M
authors: Meyer
authors: Department of Radiology, University of Groningen, University Medical Center Groningen, Hanzeplein 1, EB44, 9713 GZ, Groningen, The Netherlands.
authors: Marcel J W
authors: MJ
authors: Greuter
authors: Institute of Clinical Radiology and Nuclear Medicine, Medical Faculty Mannheim, University Medical Center Mannheim, Heidelberg University, Heidelberg, Germany.
authors: Thomas
authors: T
authors: Henzler
authors: Siemens Healthcare GmbH, Computed Tomography, Forchheim, Germany.
authors: Thomas G
authors: TG
authors: Flohr
authors: Center for Medical Imaging North-East Netherlands (CMI-NEN), University of Groningen, University Medical Center Groningen, Hanzeplein 1, Groningen, The Netherlands.
authors: Matthijs
authors: M
authors: Oudkerk
authors: Department of Radiology, University of Groningen, University Medical Center Groningen, Hanzeplein 1, EB44, 9713 GZ, Groningen, The Netherlands. r.vliegenthart@umcg.nl.|Center for Medical Imaging North-East Netherlands (CMI-NEN), University of Groningen, University Medical Center Groningen, Hanzeplein 1, Groningen, The Netherlands. r.vliegenthart@umcg.nl.
authors: Rozemarijn
authors: R
authors: Vliegenthart
mesh_terms: D002114:Calcinosis / Q000000981:diagnostic imaging*; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging*; D004562:Electrocardiography; D005240:Feasibility Studies; D006801:Humans; D019047:Phantoms, Imaging; D011829:Radiation Dosage; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods; D015203:Reproducibility of Results; D014057:Tomography, X-Ray Computed / Q000379:methods
keywords: Cardiovascular Diseases; Computed tomography; Coronary arteriosclerosis; Imaging; Mass screening