title: Occupational exposure from common fluoroscopic projections used in orthopaedic surgery.
abstract: BACKGROUND
  Personnel assisting in or performing fluoroscopically guided procedures may be exposed to high doses of radiation. Accurate occupational dosimetric data for the orthopaedic theater staff are of paramount importance for practicing radiation safety.
  
  
  METHODS
  Fluoroscopic screening was performed on an anthropomorphic phantom with use of four projections common in image-guided orthopaedic surgery. The simulated projections were categorized, according to the imaged anatomic area and the beam orientation, as (1) hip joint posterior-anterior, (2) hip joint lateral cross-table 45 degrees, (3) lumbar spine anterior-posterior, and (4) lumbar spine lateral 90 degrees. The scattered air kerma rate was measured on a grid surrounding the operating table. For each grid point, the effective dose, eye lens dose, and face skin dose values, normalized over the tube dose area product, were derived. For the effective dose calculations, three radiation protection conditions were considered: (1) with the exposed personnel using no protection measures, (2) with the exposed personnel wearing a 0.5-mm lead-equivalent protective apron, and (3) with the exposed personnel wearing both an apron and a thyroid collar. Maximum permissible workloads for typical hip, spine, and kyphoplasty procedures were derived on the basis of compliance with effective dose, eye lens dose, and skin dose limits.
  
  
  RESULTS
  We found that the effective dose, eye lens dose, and face skin dose to an orthopaedic surgeon wearing a 0.5-mm lead-equivalent apron will not exceed the corresponding limits if the dose area product of the fluoroscopically guided procedure is <0.38 Gy m (2). When protective eye goggles are also worn, the maximum permissible dose area product increases to 0.70 Gy m (2), while the additional use of a thyroid shield allows a workload of 1.20 Gy m (2). The effective dose to the orthopaedic surgeon working tableside during a typical hip, spine, kyphoplasty procedure was 5.1, 21, and 250 micro Sv, respectively, when a 0.5-mm lead-equivalent apron alone was used. The additional use of a thyroid shield reduced the effective dose to 2.4, 8.4, and 96 micro Sv per typical hip, spine, and kyphoplasty procedure, respectively.
  
  
  CONCLUSIONS
  The levels of occupational exposure vary considerably with the type of fluoroscopically assisted procedure, staff positioning, and the radiation protection measures used. The data presented in the current study will allow for accurate estimation of the occupational dose to orthopaedic theater personnel.
authors.affiliation: University Hospital of Iraklion, Crete, Greece.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Theocharopoulos
authors.forename: Kostas
authors.initials: K
authors.lastname: Perisinakis
authors.forename: John
authors.initials: J
authors.lastname: Damilakis
authors.forename: George
authors.initials: G
authors.lastname: Papadokostakis
authors.forename: Alexander
authors.initials: A
authors.lastname: Hadjipavlou
authors.forename: Nicholas
authors.initials: N
authors.lastname: Gourtsoyiannis
mesh_terms: D005471:Fluoroscopy; D006801:Humans; D016273:Occupational Exposure; D009985:Orthopedics; D019047:Phantoms, Imaging; D011829:Radiation Dosage; D011834:Radiation Monitoring / Q000379:methods*; D011835:Radiation Protection; D015641:Radiography, Interventional; D018570:Risk Assessment