RPRD | THE QUALITY EVALUATION of NEWLY DESIGNED DISPENSING SYSTEM for EXPOSU…

Jun-Hyung Park*, Yong-Hyun Cho, Ki-Young Hwang, Young-Chul Lee, Hong-Jae Lee, Hyun-Ju Kim

Pet center, Nuclear Medicine, Seoul National University Hospital, Seoul, Korea

Purpose

The aim of this study was to develop a dispenser system which provides effective decrease of exposure dose rate and to evaluate the quality of accuracy and precision with acquired data.

Materials and Methods

The dispensing system developed by PET Center, Seoul National University Hospital consists of Dilutor (Model 401, Gilson, U.S.A), controller, a simple computer Program and other accessories. The dispenser is connected to 18F-FDG vial by silicon tubing and sterilized needles through cylinder on the Dilutor. Initial 0.5mL volume of dispensed 18F-FDG solution in the syringe was measured by Dose calibrator. The measured value was inputted a decay correction calculator program. Injection activity is automatically calculated as volume with this program. Previous cases were mixed for 3 minutes and 0.2mL of origin volume. To improve the accuracy, we increased the time and volume, 5 minutes and 0.5mL.

Results

1,684 cases and 2,610 cases in total samples showed within ± 10%, ± 5% error range each. Average and standard deviation values were 0.99 ± 0.05, 1.00 ± 0.03. Correlation coefficient values (r) were 0.9984 and 0.9991. Limulus Amebocyte Lysate (LAL) and bacteria culture test were performed for samples on weekly basis. No positive results were detected in any of 18F- FDG product vials.

Conclusion

Operators are commonly exposed to dose rates of 0.063 microsieverts per second for 10 milicurie dispensation of 18F-FDG. In fact, it takes about minimum 25 seconds during a hand dispensation. By this survey, It has clearly shown that more than 90 % of dose rates can be decreased significantly with it. The advantages of this system are reasonable cost, worthy accuracy and precision quality and decreased exposure dose rate for small laboratories where are using radio-pharmaceuticals.

Key words: dispensing system, exposure dose rate, accuracy, precision, enormous cost benefits