title: Radiation dose reduction in fluoroscopic procedures: left varicocele embolization as a model.
abstract: OBJECTIVE
  To investigate the effect of a radiation reduction program on total dose, fluoroscopy dose per second corrected for body habitus and degree of collimation in left varicocele embolizations (LVE).
  
  
  METHODS
  A radiation reduction program for LVE was implemented, consisting of a technique minimizing fluoroscopy time, using low-dose presets, virtual collimation, and virtual patient positioning. Height, weight, fluoroscopy time, kerma area product (KAP) and reference air kerma (Ka,r) were recorded for 100 consecutive cases satisfying the inclusion criteria. For each patient, a device specific dose correction factor, determined using a phantom, was used to standardize the KAP to that of the cylindrical diameter of the standard man and a collimation index was derived from the KAP and Ka,r.
  
  
  RESULTS
  Median fluoroscopy time was 3 minutes (mean 4.5, range 1-23.8). Median KAP was 0.54 Gy/cm(2) (mean 0.82, range 0.12-6.52). There was a significant decrease in KAP/second corrected for cylindrical diameter (p < 0.001) and the collimation index (p < 0.001) over time.
  
  
  CONCLUSIONS
  This study shows that a dedicated dose reduction program can achieve very low total radiation dose rates for LVE. The significant decrease in collimation index and standardized KAP per second during this study suggest a learning curve for collimation.
  
  
  CONCLUSIONS
  • Left varicocele embolization can be performed with very low radiation doses. • The most effective real time radiation reduction measure is collimation. • There is a learning curve to achieving optimal collimation.
authors.affiliation: Department of Radiology, Interventional Radiology Unit, Shaare Zedek Medical Center, POB 3235, Jerusalem, Israel, 91031, anthonyv@szmc.org.il.
authors.forename: Anthony G
authors.initials: AG
authors.lastname: Verstandig
authors.forename: Bashar
authors.initials: B
authors.lastname: Shamieh
authors.forename: Vladimir
authors.initials: V
authors.lastname: Shraibman
authors.forename: David
authors.initials: D
authors.lastname: Raveh
mesh_terms: D000293:Adolescent; D000328:Adult; D004621:Embolization, Therapeutic; D005471:Fluoroscopy; D006801:Humans; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D019047:Phantoms, Imaging; D011829:Radiation Dosage; D013997:Time Factors; D014646:Varicocele / Q000000981:diagnostic imaging* / Q000628:therapy*; D055815:Young Adult