title: High-pitch 128-slice dual-source CT for the assessment of coronary stents in a phantom model.
abstract: OBJECTIVE
  To evaluate the quality of stent lumen delineation using dual-source computed tomography (DSCT) in the standard-pitch mode (SP) as compared to the high-pitch mode (HP) in a phantom study.
  
  
  METHODS
  Forty different coronary stents placed in plastic tubes filled with contrast agent were imaged with a second generation DSCT system in a SP (pitch 0.23) and HP (pitch 3.4) mode in orientations of 0°, 45°, and 90° relative to the z-axis. Two observers independently measured the in-stent lumen and the attenuation values in the center of the stents. The artificial lumen narrowing (ALN) was calculated using the measured in-stent lumen and the nominal diameter of the plastic tube.
  
  
  RESULTS
  Interobserver correlation was excellent for in-stent lumen (0.86) and attenuation measurements (0.91). There was no significant difference neither for ALN (SP: 54.7-62.8%; HP: 55.8-64.0%) nor attenuation (SP: 356-395 Hounsfield units [HU]; HP: 352-384 HU) between SP and HP mode. For both modes, the orientation of the stent relative to the z-axis significantly affected ALN and attenuation (each P < .001). CT volume dose index was significantly lower using HP mode as compared to SP mode (P < .001).
  
  
  CONCLUSIONS
  The HP mode in DSCT provides visualization of the coronary in-stent lumen comparable to that measured in SP mode while reducing applied radiation dose in a stationary phantom model.
authors.affiliation: Institute of Diagnostic Radiology, University Hospital Zurich, Raemistrasse 100, 8091 Zurich, Switzerland.
authors.forename: Olivio F
authors.initials: OF
authors.lastname: Donati
authors.forename: Matthias C
authors.initials: MC
authors.lastname: Burg
authors.forename: Lotus
authors.initials: L
authors.lastname: Desbiolles
authors.forename: Christoph
authors.initials: C
authors.lastname: Karlo
authors.forename: Paul
authors.initials: P
authors.lastname: Stolzmann
authors.forename: Alexander
authors.initials: A
authors.lastname: Bunck
authors.forename: Stephan
authors.initials: S
authors.lastname: Baumueller
authors.forename: Borut
authors.initials: B
authors.lastname: Marincek
authors.forename: Harald
authors.initials: H
authors.lastname: Seifarth
authors.forename: Hatem
authors.initials: H
authors.lastname: Alkadhi
authors.forename: Sebastian
authors.initials: S
authors.lastname: Leschka
authors.forename: David
authors.initials: D
authors.lastname: Maintz
mesh_terms: D001807:Blood Vessel Prosthesis; D017023:Coronary Angiography / Q000295:instrumentation / Q000379:methods*; D003331:Coronary Vessels / Q000601:surgery*; D006801:Humans; D019047:Phantoms, Imaging; D011856:Radiographic Image Enhancement / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D015607:Stents; D014057:Tomography, X-Ray Computed / Q000295:instrumentation / Q000379:methods*