title: Evaluation of High-Pitch Ungated Pediatric Cardiovascular Computed Tomography for the Assessment of Cardiac Structures in Neonates.
abstract: OBJECTIVE
  We evaluated a high-pitch, non-electrocardiogram-gated cardiac computed tomographic protocol, designed to image both cardiac and extracardiac structures, including coronary arteries, in a neonatal population (less than 1 year old) that was referred for congenital heart disease assessment and compared it with an optimized standard-pitch protocol in an equivalent cohort.
  
  
  METHODS
  Twenty-nine high-pitch scans were compared with 31 age-matched, sex-matched, and weight-matched standard-pitch, dosimetrically equivalent scans. The visualization and subjective quality of both cardiac and extracardiac structures were scored by consensus between 2 trained blinded observers. Image noise, signal-to-noise and contrast-to-noise ratios, and radiation doses were also compared.
  
  
  RESULTS
  The high-pitch protocol better demonstrated the pulmonary veins (P=0.03) and all coronary segments (all P<0.05), except the distal right coronary artery (P=0.10), with no significant difference in the visualization of the remaining cardiac or extracardiac structures. Both contrast-to-noise and signal-to-noise ratios improved due to greater vessel opacity, with significantly fewer streak (P<0.01) and motion (P<0.01) artifacts. Image noise and computed tomographic dose index were comparable across the 2 techniques; however, the high-pitch acquisition resulted in a small, but statistically significant, increase in dose-length product [13.0 mGy.cm (9.0 to 17.3) vs. 11.0 mGy.cm (9.0 to 13.0), P=0.05] due to greater z-overscanning.
  
  
  CONCLUSIONS
  In neonates, a high-pitch protocol improves coronary artery and pulmonary vein delineation compared with the standard-pitch protocol, allowing a more comprehensive assessment of cardiovascular anatomy while obviating the need for either patient sedation or heart rate control.
authors.affiliation: Departments of *Radiology †Cardiology, Royal Brompton Hospital, Sydney Street ‡Joint Department of Physics, The Royal Marsden, Fulham Road §Department of Radiology, Great Ormond Street Hospital, Great Ormond Street ∥National Heart and Lung Institute, Faculty of Medicine, Imperial College, London.
authors.forename: Mona
authors.initials: M
authors.lastname: Sriharan
authors.forename: Olga
authors.initials: O
authors.lastname: Lazoura
authors.forename: Christopher W
authors.initials: CW
authors.lastname: Pavitt
authors.forename: Isabel
authors.initials: I
authors.lastname: Castellano
authors.forename: Catherine M
authors.initials: CM
authors.lastname: Owens
authors.forename: Michael B
authors.initials: MB
authors.lastname: Rubens
authors.forename: Simon P G
authors.initials: SP
authors.lastname: Padley
authors.forename: Edward D
authors.initials: ED
authors.lastname: Nicol
mesh_terms: D017023:Coronary Angiography / Q000379:methods*; D006321:Heart / Q000000981:diagnostic imaging; D006330:Heart Defects, Congenital / Q000000981:diagnostic imaging*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D011829:Radiation Dosage; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D059629:Signal-To-Noise Ratio; D014057:Tomography, X-Ray Computed / Q000379:methods*