Prussin S G, Theofanous G, Casey D, Kim A
Department of Nuclear Engineering, University of California Berkeley 94720, USA.
J Nucl Med Technol. 1998 Mar;26(1):32-7.
We examined the dose from 99mTc contained in syringes and shielded vials to assess in detail the dose burdens in a central pharmacy.
Absorbed-dose rates at the end of the plunger of a shielded syringe, when 99mTc is contained either in the syringe or in a shielded vial from which the activity would be drawn, were measured with CaF2 dosimeters. The dose rates also were calculated with a Monte Carlo model.
When activity was contained in either 3-ml or 10-ml disposable syringes shielded by lead glass, the absorbed-dose rates were 1.35-1.62 mGy hr-1 GBq-1 (5-6 mrad hr-1 mCi-1). When the activity was contained in either a shielded elution or product kit vial, the absorbed-dose rates at the end of the syringe plunger were about 0.40 mGy hr-1 GBq-1 (1.4-1.5 mrad hr-1 mCi-1). These results were reproduced with reasonable accuracy by Monte Carlo simulations.
The dose burden per unit of activity handled from 99mTc in procedures using syringes is likely to be two to five times larger than the dose burden from calibrating generator eluate. The Monte Carlo simulations suggest that lead K x-rays may be responsible for a significant fraction of the total dose to the fingers and hand of the pharmacist when lead-glass syringe shields are used.
我们检测了注射器和屏蔽瓶中所含99mTc的剂量，以详细评估中心药房的剂量负担。
使用CaF2剂量计测量屏蔽注射器活塞末端的吸收剂量率，此时99mTc要么包含在注射器中，要么包含在从中抽取放射性活度的屏蔽瓶中。剂量率也用蒙特卡罗模型计算。
当活度包含在由铅玻璃屏蔽的3毫升或10毫升一次性注射器中时，吸收剂量率为1.35 - 1.62 mGy·hr-1·GBq-1（5 - 6 mrad·hr-1·mCi-1）。当活度包含在屏蔽洗脱或产品试剂盒瓶中时，注射器活塞末端的吸收剂量率约为0.40 mGy·hr-1·GBq-1（1.4 - 1.5 mrad·hr-1·mCi-1）。蒙特卡罗模拟以合理的准确度重现了这些结果。
在使用注射器的操作中，每处理单位活度的99mTc所产生的剂量负担可能比校准发生器洗脱液所产生的剂量负担大两到五倍。蒙特卡罗模拟表明，当使用铅玻璃注射器屏蔽时，铅K x射线可能占药剂师手指和手部总剂量的很大一部分。
