title: Evaluation of radiation during EVAR performed on a mobile C-arm.
abstract: BACKGROUND
  The aim of this study was to evaluate radiation exposure during aortic endovascular aneurysm repair (EVAR) on a mobile C-arm using a low dose and pulse mode.
  
  
  METHODS
  We performed a retrospective analysis of a prospectively maintained database on patients undergoing EVAR. Indirect dose measurements of dose area product (DAP, mGy m²) calculated by the C-arm (OEC 9900MD), fluoroscopic time (FT), type of procedure, contrast media volume and body mass index were analysed. To confirm the correlation between direct and indirect DAP measurements, direct dose was measured with radiochromic films on a sample of 15 patients. Film grey level response was calibrated according to a reference dose measurement performed with a calibrated dosimeter. DAP and peak skin dose (PSD, Gy) were measured on each film. Correlation between DAP from direct and indirect measures, and between DAP and PSD, were analysed.
  
  
  RESULTS
  From January 2009 to April 2011, 335 patients underwent EVAR. Complete data were available on 301 procedures including 188 bifurcated, 54 fenestrated, 28 thoracic, 20 branched and 11 aorto-uni-iliac endografts implantation. The respective median FT and DAP was 9.36 min (1.8-67) and 3 mGy m(2) (0.4-28); 27.2 min (2-69) and 7.3 mGy m(2) (1.2-29); 7.75 min (1.2-19.1) and 2 mGy m(2) (0.3-11); 42.98 min (2.4-95.4) and 15.95 mGy m(2) (2.98-77.7); 6.2 min (0.5-36.3) and 2 mGy m(2) (0.3-11). Direct DAP measurement on radiochromic films was strongly correlated with DAP values provided by the C-arm (r = 0.98). PSD correlated weakly with DAP. DAP was significantly increased (p < 0.001) in patients with a body mass index >30. Contrast media volume was significantly increased in the branched endograft group.
  
  
  CONCLUSIONS
  Indirect DAP values measured by the C-arm are accurate to evaluate radiation exposure. Compared to the literature, our values for standard procedures are significantly decreased by the usage of low dose and pulse mode. DAP for fenestrated and branched procedures was comparable to published DAP values with standard procedures using a regular fluoroscopic mode.
authors: Department of Vascular Surgery and Radiology, Hôpital Cardiologique, CHRU de Lille, France.
authors: B
authors: B
authors: Maurel
authors: J
authors: J
authors: Sobocinski
authors: P
authors: P
authors: Perini
authors: M
authors: M
authors: Guillou
authors: M
authors: M
authors: Midulla
authors: R
authors: R
authors: Azzaoui
authors: S
authors: S
authors: Haulon
mesh_terms: D001014:Aortic Aneurysm / Q000000981:diagnostic imaging* / Q000601:surgery*; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation*; D015992:Body Mass Index; D003287:Contrast Media; D057510:Endovascular Procedures / Q000009:adverse effects / Q000295:instrumentation*; D004867:Equipment Design; D005373:Film Dosimetry; D005471:Fluoroscopy; D005602:France; D006801:Humans; D011829:Radiation Dosage; D015641:Radiography, Interventional / Q000009:adverse effects / Q000295:instrumentation*; D012189:Retrospective Studies; D018570:Risk Assessment; D012867:Skin / Q000528:radiation effects; D013997:Time Factors
chemical_list: D003287:Contrast Media