Exposure to Technologists: Is the Implication of an Automatic Infusion Device Crucial to the Safety of PET Personnel?

Objectives: This study was completed to determine if the application of an automatic infusion device is necessary to the reduction of exposure to Nuclear Medicine Technologists.

Background: Positron Emission Tomography (PET) has seen substantial growth at our health system in recent years. The radiopharmaceutical utilized in the majority of basic PET procedures is F - 18 Fluorodeoxyglucose. The exposure rate of high energy F-18 at 1 cm from 5 mCi is 28.2 R/hr¹. This number is significant because doses of F-18 Fluorodeoxyglucose are between 10-14 mCi, depending on the weight of the patient to receive the injection.

Methods: The study was performed by obtaining the extremity dose readings for the Nuclear Medicine Technologist that spends the bulk of her shifts in the PET department. The years obtained for the dose readings were 2016 through 2019. The automatic injection device was implemented in January of 2018, giving ample data points on each side of the study. A t-test was performed to establish if the difference in exposure was statistically significant.

Results: The t-test yielded a value of 2.018. With 42 degrees of freedom at a 0.05 confidence level the critical value was 1.9028. The calculated t value was less than the critical value indicating that the difference in the mean exposure rates are not statistically significant.

Conclusions: This study didn’t demonstrate a statistical difference in exposure to the technologist but did illustrate a reduction to the extremity readings as shown in a graphical representation; concluding that an automatic injection system follows the ALARA principle. Being that the dosimetry readings that were obtained are not exclusive to PET procedures only, future studies should consider using separate ring badges to be utilized only when in PET to then compare the exposure rates between unit doses and an automatic injection system.