title: Lightweight bilayer barium sulfate-bismuth oxide composite thyroid collars for superior radiation protection in fluoroscopy-guided interventions: a prospective randomized controlled trial.
abstract: OBJECTIVE
  To test whether newer bilayer barium sulfate-bismuth oxide composite (XPF) thyroid collars (TCs) provide superior radiation protection and comfort during fluoroscopy-guided interventions compared with standard 0.5-mm lead-equivalent TCs.
  
  
  METHODS
  Institutional review board approval and written informed consent were obtained for this HIPAA-compliant study, and 144 fluoroscopy-guided vascular interventions were included at one center between October 2011 and July 2012, with up to two operators randomly assigned to wear XPF (n = 135) or standard 0.5-mm lead-equivalent (n = 121) TCs. Radiation doses were measured by using dosimeters placed outside and underneath the TCs. Wearing comfort was assessed at the end of each procedure on a visual analog scale (0-100, with 100 indicating optimal comfort). Adjusted differences in comfort and radiation dose reductions were calculated by using a mixed logistic regression model and the common method of inverse variance weighting, respectively.
  
  
  RESULTS
  Patient (height, weight, and body mass index) and procedure (type and duration of intervention, operator, fluoroscopy time, dose-area product, and air kerma) data did not differ between the XPF and standard groups. Comfort was assessed in all 256 measurements. On average, the XPF TCs were 47.6% lighter than the standard TCs (mean weight ± standard deviation, 133 g ± 14 vs 254 g ± 44; P < .001) and had a significantly higher likelihood of a high level of comfort (visual analog scale >90; odds ratio, 7.6; 95% confidence interval: 3.0, 19.2; P < .001). Radiation dose reduction provided by the TCs was analyzed in 117 data sets (60 in the XPF group, 57 in the standard group). The mean radiation dose reductions (ie, radiation protection) provided by XPF and standard TCs were 90.7% and 72.4%, with an adjusted mean difference of 17.9% (95% confidence interval: 7.7%, 28.1%; P < .001) favoring XPF.
  
  
  CONCLUSIONS
  XPF TCs are a lightweight alternative to standard 0.5-mm lead-equivalent TCs and provide superior radiation protection during fluoroscopy-guided interventions.
authors.affiliation: From the Department of Vascular and Interventional Radiology, Baptist Cardiac and Vascular Institute, 8900 N Kendall Dr, Miami, FL 33176 (H.U., M.J.B., B.T.K., C.P., R.G., M.S.); and Department of Angiology, University Hospital Basel, Basel, Switzerland (H.U., D.S.).
authors.forename: Heiko
authors.initials: H
authors.lastname: Uthoff
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Benenati
authors.forename: Barry T
authors.initials: BT
authors.lastname: Katzen
authors.forename: Constantino
authors.initials: C
authors.lastname: Peña
authors.forename: Ripal
authors.initials: R
authors.lastname: Gandhi
authors.forename: Daniel
authors.initials: D
authors.lastname: Staub
authors.forename: Melanie
authors.initials: M
authors.lastname: Schernthaner
mesh_terms: D001466:Barium Sulfate; D001729:Bismuth; D005471:Fluoroscopy; D006801:Humans; D011446:Prospective Studies; D011829:Radiation Dosage; D011832:Radiation Injuries / Q000517:prevention & control*; D011835:Radiation Protection / Q000295:instrumentation*; D015641:Radiography, Interventional; D013961:Thyroid Gland / Q000528:radiation effects
chemical_list: D001466:Barium Sulfate; C033301:bismuth oxide; D001729:Bismuth