title: C-arm flat-panel CT arthrography of the wrist and elbow: first experiences in human cadavers.
abstract: OBJECTIVE
  To determine the optimal intra-articular iodine concentration for C-arm flat-panel computed tomography (FPCT) arthrography using advanced joint phantoms and to evaluate its application in human cadaveric wrists and elbows. Multi-detector (MD) CT served as the standard of reference.
  
  
  METHODS
  Joint phantoms and 10 human cadaveric wrist and elbow joints were scanned with C-arm FPCT (5-s, 8-s, and 20-s runs) and standard MDCT using different and optimal concentrations of iodinated contrast material. CT numbers of contrast material, tissue, and noise were measured and contrast-to-noise ratios (CNR) calculated for quantitative analysis. Image and depiction of cartilage, bone, and soft tissues were rated. Radiation doses were compared.
  
  
  RESULTS
  In FPCT, iodine concentrations positively correlated with CT numbers and noise of contrast material and with radiation dose (r = 0.713-0.996, p < 0.05 each). At an iodine concentration of 45 mg/ml, CNR of cartilage and soft tissues were highest for all FPCT acquisitions and higher than in MDCT. The 20-s FPCT run performed best for image quality and depiction of anatomical structures and was rated overall equal to MDCT (p = 0.857).
  
  
  CONCLUSIONS
  The optimal iodine concentration for C-arm FPCT arthrography in this study is 45 mg/ml, leading to superior CNR and image quality for an optimal FPCT protocol compared with standard MDCT arthrography in human cadaveric joints.
authors.affiliation: Department of Radiology, University Hospital Zurich, Zurich, Switzerland. roman.guggenberger@usz.ch
authors.forename: Roman
authors.initials: R
authors.lastname: Guggenberger
authors.forename: Fabian
authors.initials: F
authors.lastname: Morsbach
authors.forename: Hatem
authors.initials: H
authors.lastname: Alkadhi
authors.forename: Magdalena
authors.initials: M
authors.lastname: Vich
authors.forename: Thomas
authors.initials: T
authors.lastname: Pfammatter
authors.forename: Juerg
authors.initials: J
authors.lastname: Hodler
authors.forename: Gustav
authors.initials: G
authors.lastname: Andreisek
mesh_terms: D001175:Arthrography / Q000295:instrumentation* / Q000379:methods; D002102:Cadaver; D003287:Contrast Media / Q000008:administration & dosage; D004305:Dose-Response Relationship, Drug; D004551:Elbow Joint / Q000000981:diagnostic imaging*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005260:Female; D006801:Humans; D007472:Iohexol / Q000008:administration & dosage / Q000031:analogs & derivatives*; D008297:Male; D010865:Pilot Projects; D011856:Radiographic Image Enhancement / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000295:instrumentation* / Q000379:methods; D014955:Wrist Joint / Q000000981:diagnostic imaging*; D014963:X-Ray Intensifying Screens
chemical_list: D003287:Contrast Media; D007472:Iohexol; C038192:iopromide