title: An engagement factor for caregiver radiation dose assessment with radioiodine treatment.
abstract: This study aims to suggest ways to better manage thyroid cancer patients treated with high- and low-activity radioiodine ((131)I) by assessing external radiation doses to family members and caregivers and the level of radiation in the surrounding environment. The radiation doses to caregivers of 33 inpatients (who were quarantined in the hospital for 2-3 d after treatment) and 31 outpatients who received radioiodine treatment after thyroidectomy were measured using passive thermoluminescence dosemeters. In this study, 33 inpatients were administered high-activity (100-200 mCi) (131)I, and 31 outpatients were administered low-activity (30 mCi) (131)I. The average doses to caregivers were measured at 0.61 mSv for outpatients and 0.16 mSv for inpatients. The total integrated dose of the recovery (recuperation) rooms where the patients stayed after release from hospital was measured to be 0.83 mSv for outpatients and 0.23 mSv for inpatients. To reflect the degree of engagement between the caregiver and the patient, considering the duration and distance between two during exposure, the authors used the engagement factor introduced by Jeong et al. (Estimation of external radiation dose to caregivers of patients treated with radioiodine after thyroidectomy. Health Phys 2014; 106: :466-474.). This study presents a new engagement factor (K-value) of 0.82 obtained from the radiation doses to caregivers of both in- and out-patients treated with high- and low-activity radioiodine, and based on this new value, this study presented a new predicted dose for caregivers. A patient treated with high-activity radioiodine can be released after 24 h of isolation, whereas outpatients treated with low-activity radioiodine should be isolated for at least 12 h.
authors.affiliation: Department of Nuclear Medicine, Eulji University Hospital, Daejeon, Korea Department of Radiological Science, Eulji University, Seongnam, Korea.
authors.forename: Hyun Kuk
authors.initials: HK
authors.lastname: Lee
authors.affiliation: Department of Radiological Science, Eulji University, Seongnam, Korea Department of Senior Healthcare, Eulji University Graduate School, Daejeon, Korea hongseongj@eulji.ac.kr.
authors.forename: Seong Jong
authors.initials: SJ
authors.lastname: Hong
authors.affiliation: Department of Radiation Safety, Korea Institute of Nuclear Safety, Daejeon, Korea.
authors.forename: Kyu Hwan
authors.initials: KH
authors.lastname: Jeong
authors.affiliation: Department of Physics, East Carolina University, Greenville, NC, USA.
authors.forename: Jae Won
authors.initials: JW
authors.lastname: Jung
authors.affiliation: Department of Nuclear Medicine, Chungnam National University Hospital, Daejeon, Korea.
authors.forename: Seong Min
authors.initials: SM
authors.lastname: Kim
authors.affiliation: Department of Nuclear Medicine, Eulji University Hospital, Daejeon, Korea.
authors.forename: Yun-Hee
authors.initials: YH
authors.lastname: Kang
authors.affiliation: Department of Radiological Science, Kangwon National University, Samcheok, Korea.
authors.forename: Man Seok
authors.initials: MS
authors.lastname: Han
mesh_terms: D017028:Caregivers; D002648:Child; D004781:Environmental Exposure / Q000032:analysis*; D005190:Family; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes / Q000009:adverse effects / Q000032:analysis* / Q000627:therapeutic use; D008297:Male; D016273:Occupational Exposure / Q000032:analysis*; D010351:Patient Discharge; D011835:Radiation Protection; D011879:Radiotherapy Dosage; D013819:Thermoluminescent Dosimetry; D013964:Thyroid Neoplasms / Q000378:metabolism / Q000473:pathology / Q000532:radiotherapy*
chemical_list: D007457:Iodine Radioisotopes