90Y microspheres radioembolization is an emerging treatment modality for treatment of liver malignancies [1]. Radioembolisation involves placing a radioactive material, tiny resin or glass beads called microspheres directly at the tumor site under the guidance of interventional radiology technique. With better understanding to the dose-response of the treatment, there is a trend to adminster higher 90Y radioactivity for better patient efficacy [1], raising the concern in occupational radiation dose received by medical personnel caring for this new patient service [2]. Although there are local guidelines...

Y90 is pure β-emitting isotope of average energy of 0.9 MeV, a maximum radiation range of 11 mm in tissue and of half life of 64 hours. Following treatment of 90Y microspheres, patients become a source of radiation that could potentially affect other persons around them via Bremsstrahlung emission [4]. Therefore safety precautions must be considered to keep the dose to other individuals as low as reasonably achievable. Because Bremsstrahlu`ng emission is in the form of γ-radiation, lead apron type blanket is useful to reduce...

Table 1 shows the dose rates, normalised by the patient administered 90Y microsphere radioactivity, measured at the position of the interventional radiologist and at 10 cm above the patient abdomen with and without being covered by the lead lined blanket. There has been a dose reduction of a factor of > 2 with the use of the blanket. At the radiologist position during pressing the puncture site after radioembolisation, the average dose rate has been measured as 1.32 μSv/(hr GBq). The average infused Y90 radioactivity...

A simple but practical measure of using a lead lined blanket not only further reduces occupational dose to personnel providing patient service for the radioembolisation procedure but also solves limited resource of isolation ward.

aM Law, aKK Wong, aWK Tso, bV Lee, bMY Luk aDepartment of Radiology and bClinical Oncology, Queen Mary Hospital, Hong Kong

Lam MGEH, Louie JD, Abdelmaksoud MHK, et al. Limitations of body surface area-based activity calculation for radioembolization of hepatic metastases in colorectal cancer. J Vasc Interv Radiol 2014;25:1085-1093. Kim YC, Kim YH, Uhm YH et al. Radiation Safety Issues in Y-90 Microsphere Selective Hepatic Radioembolization Therapy: Possible Radiation Exposure from the Patients. Nucl Med and Molecular Imag 2010;44:252-260. ICRP. 2007 Recommendations of the International Commission on Radiological Protection. Ann ICRP 2007;2-4:1-332 [publication 103]. Gulec SA, Siegel JA. Posttherapy radiatiom safety considerations in radiomicrosphere treatment with...