title: Usefulness of multidetector CT imaging to assess vascular stents in children with congenital heart disease: an in vivo and in vitro study.
abstract: OBJECTIVE
  To evaluate varying CT settings to visualize pediatric vascular stents in comparison to digital angiography (DA).
  
  
  BACKGROUND
  There is a great clinical interest in substituting noninvasive methods to follow up children with congenital heart disease after interventional treatment.
  
  
  METHODS
  CT studies in small children with transcatheter placed stents were reviewed, retrospectively. Furthermore, eight stents were implanted in tubes and partially obstructed. CT exams were performed on varying scanners (4 up to 64 slices) with corresponding tube settings. The effects of dose on image quality were evaluated regarding stent size, strut thickness, and in-stent stenoses in comparison to DA.
  
  
  RESULTS
  Fourteen children with 28 implanted stents were identified. Significant differences between higher and lower radiation settings were not found, corresponding with the phantom, where moderate tube setting showed the best results. In vitro, there was an improvement with increasing number of detector rows, which resulted in a decrease of stent strut overestimation (295% down to 201%; P < 0.0001) and a better agreement with DA measurements for mild (78% up to 91%; P = 0.003) and moderate in-stent stenoses (80% up to 99%; P = 0.0001).
  
  
  CONCLUSIONS
  Higher radiation exposure settings did not improve image quality, suggesting that the exams could be performed at a lower radiation dose.
authors.affiliation: Department of Radiology, Ohio State University College of Medicine, Columbus, Ohio, USA. eichhorn.12@osu.edu
authors.forename: Joachim G
authors.initials: JG
authors.lastname: Eichhorn
authors.forename: Frederick R
authors.initials: FR
authors.lastname: Long
authors.forename: Claudia
authors.initials: C
authors.lastname: Jourdan
authors.forename: Johannes T
authors.initials: JT
authors.lastname: Heverhagen
authors.forename: Sharon L
authors.initials: SL
authors.lastname: Hill
authors.forename: Subha V
authors.initials: SV
authors.lastname: Raman
authors.forename: John P
authors.initials: JP
authors.lastname: Cheatham
mesh_terms: D015901:Angiography, Digital Subtraction; D016477:Artifacts; D006328:Cardiac Catheterization / Q000009:adverse effects / Q000295:instrumentation*; D002675:Child, Preschool; D003251:Constriction, Pathologic; D017023:Coronary Angiography / Q000379:methods*; D005240:Feasibility Studies; D005260:Female; D006083:Graft Occlusion, Vascular / Q000000981:diagnostic imaging* / Q000209:etiology; D006330:Heart Defects, Congenital / Q000000981:diagnostic imaging / Q000628:therapy*; D006801:Humans; D007223:Infant; D008297:Male; D019047:Phantoms, Imaging; D011237:Predictive Value of Tests; D011829:Radiation Dosage; D011857:Radiographic Image Interpretation, Computer-Assisted; D015641:Radiography, Interventional / Q000379:methods*; D012189:Retrospective Studies; D015607:Stents; D014057:Tomography, X-Ray Computed