title: Coronary Computed Tomography Angiography: Patient-related factors determining image quality using a second-generation 320-slice CT scanner.
abstract: OBJECTIVE
  To investigate the diagnostic confidence of Coronary Computed Tomography Angiography (CCTA) and the effect of patient-related factors on CCTA image quality using a second-generation 320-slice scanner.
  
  
  RESULTS
  200 consecutive patients (mean age 60±12years; 109 men) prospectively underwent CCTA. The mean body mass index (BMI) was 27.1±4.9kg/m(2); the median heart rate (HR) was 60.0 (interquartile range (IQR), 53.9-66.1) beats per minute (bpm). The median segment's diameter was 2.8 (IQR, 2.2-3.4) mm. For each coronary segment ≥1.5mm in diameter, two readers scored: diameter narrowing as < or ≥50%, overall diagnostic confidence and motion-related image quality, with interobserver agreement kappa-values of 0.89, 0.91 and 0.61 respectively. Seventy-nine of the 2505 evaluated segments (3.2%) had non-diagnostic image quality because of coronary calcifications (66/79; 83.5%), stent- (6/79; 7.5%), pacemaker- (2/79; 2.5%) or motion-related artifacts (5/79; 6.5%). The effect of patient-related factors on motion-related image quality was investigated by multinomial logistic regression in 181 patients with calcium score (IQR, 0-446.5). Increasing coronary diameter was the most improving image quality factor (odds ratio (OR), 1.8637; p<0.001), marginally followed by lower HR (OR, 0.9547; p<0.001) and calcium score (OR, 0.9997; p=0.04). Gender (p=0.70), age (p=0.24) and BMI (p=0.45) did not affect image quality.
  
  
  CONCLUSIONS
  Using a second-generation 320-slice scanner, CCTA diagnostic confidence is predominantly affected by coronary calcifications, whereas motion-related image quality is non-diagnostic only in exceptional cases and mainly influenced by the coronary diameter. For future developments, our study findings therefore suggest greater requirements concerning spatial resolution and calcium-related artifact removal than concerning temporal resolution, especially to improve diagnostic confidence in patient groups with smaller coronary diameters.
authors.affiliation: Department of Radiology, Centre Hospitalier Chrétien (CHC), Rue de Hesbaye, 75, B-4000 Liège, Belgium; Department of Radiology, Jessa Hospital, Stadsomvaart 11, B-3500 Hasselt, Belgium; Faculty of Medicine and Life Sciences, Biomed and Reval, Hasselt University, Agoralaan, Building A and C, B-3500 Hasselt, Belgium. Electronic address: olivierghekiere@gmail.com.
authors.forename: Olivier
authors.initials: O
authors.lastname: Ghekiere
authors.affiliation: Liège University (ULg), GIGA Cardiovascular Sciences, Domaine Universitaire du Sart Tilman, Rue de l'hôpital, 1, B-4000 Liège, Belgium.
authors.forename: Alain
authors.initials: A
authors.lastname: Nchimi
authors.affiliation: Department of Radiology, Centre Hospitalier Chrétien (CHC), Rue de Hesbaye, 75, B-4000 Liège, Belgium.
authors.forename: Julien
authors.initials: J
authors.lastname: Djekic
authors.affiliation: Liège University (ULg), GIGA Cardiovascular Sciences, Domaine Universitaire du Sart Tilman, Rue de l'hôpital, 1, B-4000 Liège, Belgium.
authors.forename: Mounia
authors.initials: M
authors.lastname: El Hachemi
authors.affiliation: Department of Radiology, Centre Hospitalier Chrétien (CHC), Rue de Hesbaye, 75, B-4000 Liège, Belgium.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Mancini
authors.affiliation: Faculty of Medicine and Life Sciences, Biomed and Reval, Hasselt University, Agoralaan, Building A and C, B-3500 Hasselt, Belgium.
authors.forename: Dominique
authors.initials: D
authors.lastname: Hansen
authors.affiliation: Department of Radiology, OLV Hospital Aalst, Moorselbaan 164, B-9300 Aalst, Belgium.
authors.forename: Piet
authors.initials: P
authors.lastname: Vanhoenacker
authors.affiliation: Department of Radiology, Leiden University Medical Center, Albinusdreef, 2, NL-2333 ZA Leiden, The Netherlands.
authors.forename: Albert
authors.initials: A
authors.lastname: de Roos
authors.affiliation: Faculty of Medicine and Life Sciences, Biomed and Reval, Hasselt University, Agoralaan, Building A and C, B-3500 Hasselt, Belgium; Heart Center Hasselt, Jessa Hospital, Stadsomvaart, 11, B-3500 Hasselt, Belgium.
authors.forename: Paul
authors.initials: P
authors.lastname: Dendale
mesh_terms: D000368:Aged; D000072226:Computed Tomography Angiography / Q000295:instrumentation / Q000379:methods; D017023:Coronary Angiography / Q000295:instrumentation / Q000379:methods; D003324:Coronary Artery Disease / Q000175:diagnosis*; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000473:pathology; D000068598:Data Accuracy; D061827:Dimensional Measurement Accuracy; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009929:Organ Size; D015203:Reproducibility of Results; D015898:Tomography Scanners, X-Ray Computed / Q000592:standards; D061205:Vascular Calcification / Q000473:pathology
keywords: Coronary CT angiography; Coronary calcifications; Coronary diameter; Diagnostic confidence; Image quality; Patient-related factors