title: Radiation emission from patients treated with selective hepatic radioembolization using yttrium-90 microspheres: are contact restrictions necessary?
abstract: OBJECTIVE
  To estimate the possible radiation dose to other individuals from patients treated with yttrium-90 ((90)Y).
  
  
  METHODS
  Dosimetry data were analyzed after 143 consecutive administrations of (90)Y (124 resin, 19 glass) in 86 patients. External radiation exposure levels from patients were measured immediately after infusion. Total effective dose equivalent (TEDE) to maximally exposed individuals was calculated based on total body residence time and measured dose rate. These values were compared to Nuclear Regulatory Commission (NRC) regulations (maximum, 1 mSv) and other potential guidelines for caregivers, extensive caregivers, or pregnant contacts.
  
  
  RESULTS
  Mean administered activity for resin microspheres was 0.71 GBq ± 0.35 (range, 0.07-1.6GBq). Mean TEDE dose to the maximally exposed contact was 0.03 mSv (range, 0.0005-0.16 mSv). For glass microspheres, mean administered activity was 2.8 GBq ± 1.5 (range, 0.37-5.14 GBq). Mean TEDE dose to the maximally exposed contact was 0.06 mSv (range, 0.0023-0.23 mSv). All (90)Y treatments were within current NRC regulations for release without instructions. One, three, and one infusion were beyond potential thresholds for caregivers, extensive caregivers, or pregnant contacts, respectively. For any contact scenario, release without instruction was appropriate when administered activity was less than 3 GBq.
  
  
  CONCLUSIONS
  All patients treated with (90)Y hepatic radioembolization to a maximum administered activity of 5.14 GBq and maximum dose rate of 10 uSv/h were releasable without contact restrictions according to the NRC contact scenario. Patients who receive more than 3 GBq during infusion may require dose rate measurement if more restrictive contact scenarios are considered.
authors.affiliation: Interventional Radiology Division, Department of Radiology, Thomas Jefferson University, 132 S 10th St, Suite 766, Philadelphia, PA 19107, USA.
authors.forename: Jeffrey W
authors.initials: JW
authors.lastname: McCann
authors.forename: Ann M
authors.initials: AM
authors.lastname: Larkin
authors.forename: Larry J
authors.initials: LJ
authors.lastname: Martino
authors.forename: David J
authors.initials: DJ
authors.lastname: Eschelman
authors.forename: Carin F
authors.initials: CF
authors.lastname: Gonsalves
authors.forename: Daniel B
authors.initials: DB
authors.lastname: Brown
mesh_terms: D017028:Caregivers; D004621:Embolization, Therapeutic / Q000009:adverse effects / Q000379:methods*; D005260:Female; D006499:Hepatic Artery; D006801:Humans; D008113:Liver Neoplasms / Q000098:blood supply / Q000473:pathology / Q000532:radiotherapy* / Q000556:secondary; D008297:Male; D008863:Microspheres; D010351:Patient Discharge; D015143:Philadelphia; D011247:Pregnancy; D011248:Pregnancy Complications / Q000209:etiology / Q000517:prevention & control; D011829:Radiation Dosage; D011832:Radiation Injuries / Q000209:etiology / Q000517:prevention & control; D011834:Radiation Monitoring; D019275:Radiopharmaceuticals / Q000008:administration & dosage* / Q000009:adverse effects; D011879:Radiotherapy Dosage; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D015021:Yttrium Radioisotopes / Q000008:administration & dosage* / Q000009:adverse effects
chemical_list: D019275:Radiopharmaceuticals; D015021:Yttrium Radioisotopes