title: Time-limited fluoroscopy to reduce radiation exposure during ERCP: a prospective randomized trial.
abstract: BACKGROUND
  Measures should be used to limit radiation exposure of the staff and patients during ERCP.
  
  
  OBJECTIVE
  To determine whether "time-limited fluoroscopy" reduces radiation exposure and fluoroscopy time (FT) compared with continuous fluoroscopy.
  
  
  METHODS
  Prospective randomized trial.
  
  
  METHODS
  Tertiary academic medical center.
  
  
  METHODS
  Consecutive adult patients presenting for ERCP.
  
  
  METHODS
  Subjects were randomized into 2 fluoroscopy setting groups: (1) time-limited, where x-ray exposure is limited to 3 seconds each time the foot-operated switch is depressed; (2) continuous, where x-ray exposure continues for as long as the switch is depressed.
  
  
  METHODS
  FT, patient, and procedure-related data were recorded. Radiation dosimetry badges were used to estimate cumulative exposure.
  
  
  RESULTS
  Ninety-nine procedures were performed in the time-limited group and 100 by using continuous fluoroscopy. The mean FT for time-limited fluoroscopy was 284.4 seconds (95% confidence interval [CI] 247.1-321.6) and for continuous fluoroscopy was 314 seconds (95% CI 265.6-362.4; P=.34). Longer FT was associated with moderate or difficult cannulation (P=.008), lithotripsy (P<.001), stent placement (P=.007), sphincterotomy (P<.001), and longer overall procedure length (P<0.001). After controlling for confounding factors and interactions with a multiple linear regression model, time-limited fluoroscopy was associated with a 16.4% lower FT (P=.029). The average radiation dose was not amenable to multivariate analysis, and, therefore, no significant difference between groups was found.
  
  
  CONCLUSIONS
  Endoscopists were not blinded to the study group assignments.
  
  
  CONCLUSIONS
  FT and radiation exposure are dependent upon numerous patient-, operator-, and procedure-related factors. This study found that, after controlling for the impact of confounding factors, time-limited fluoroscopy significantly decreases FTs.
authors.affiliation: Division of Gastroenterology and Hepatology, University of Maryland Medical Center, Baltimore, Maryland 21201, USA.
authors.forename: Lance T
authors.initials: LT
authors.lastname: Uradomo
authors.forename: Eric M
authors.initials: EM
authors.lastname: Goldberg
authors.forename: Peter E
authors.initials: PE
authors.lastname: Darwin
mesh_terms: D000328:Adult; D001660:Biliary Tract Diseases / Q000000981:diagnostic imaging* / Q000628:therapy; D002760:Cholangiopancreatography, Endoscopic Retrograde; D005260:Female; D005373:Film Dosimetry; D005471:Fluoroscopy / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011829:Radiation Dosage; D015203:Reproducibility of Results; D013997:Time Factors