title: Radiation exposure levels of routine SPECT/CT imaging protocols.
abstract: OBJECTIVE
  To assess incremental and total patient exposure from clinical SPECT/CT imaging by means of effective dose estimations with regards to different protocols and SPECT/CT systems.
  
  
  METHODS
  Consecutive patient exposure levels were documented prospectively from SPECT/CT operations at three European imaging centers. Documentation included the volume-weighted computed tomography (CT) dose index, the CT dose length product (DLP) and the amount of applied radiopharmaceutical. SPECT/CT examinations were categorized regionally into head, neck, myocardium, thorax, abdomen, extremities and whole-body. Effective dose from the CT (EDCT) was estimated from the DLP using gender specific conversion factors. EDSPECT was estimated from the injected activity levels and corresponding conversion factors (ICRP 106).
  
  
  RESULTS
  This study included 678 SPECT/CT examinations. EDCT per indication and EDSPECT per tracer ranged from 0.01mSv to 7.4mSv and from 1.1mSv to 12.2mSv, respectively. In general, EDSPECT contributed most to overall patient exposure. Total EDSPECT/CT averaged across all protocol categories was 6.7mSv.
  
  
  CONCLUSIONS
  Total patient exposure from clinical SPECT/CT is 7mSv on average. Individual dose levels vary with the clinical indication and on-site protocol parameters.
authors: Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria. Electronic address: ivo.rausch@meduniwien.ac.at.
authors: Ivo
authors: I
authors: Rausch
authors: Department for Radiology and Nuclear Medicine, City Hospital Waid, Zurich, Switzerland.
authors: Frank G
authors: FG
authors: Füchsel
authors: Fachhochschule Wiener Neustadt, Landesklinikum Wiener Neustadt, Nuclear Medicine, Wiener Neustadt, Austria.
authors: Corinna
authors: C
authors: Kuderer
authors: University Clinic for Nuclear Medicine, Bern University Hospital, Bern, Switzerland.
authors: Michael
authors: M
authors: Hentschel
authors: Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.
authors: Thomas
authors: T
authors: Beyer
mesh_terms: D000328:Adult; D000368:Aged; D001317:Austria; D001417:Background Radiation; D001822:Body Burden; D002985:Clinical Protocols; D006801:Humans; D008297:Male; D011829:Radiation Dosage; D000069079:Radiation Exposure / Q000517:prevention & control*; D011832:Radiation Injuries / Q000517:prevention & control*; D011835:Radiation Protection / Q000379:methods*; D011874:Radiometry; D019275:Radiopharmaceuticals / Q000008:administration & dosage / Q000009:adverse effects*; D013557:Switzerland; D015899:Tomography, Emission-Computed, Single-Photon / Q000009:adverse effects / Q000379:methods; D014057:Tomography, X-Ray Computed / Q000379:methods
chemical_list: D019275:Radiopharmaceuticals
keywords: Molecular imaging; Multi-center study; Radiation dosage; SPECT/CT