Radiation protection and personal dosimetry in a core facility for multimodal small animal imaging

Abstract

Clinical imaging techniques such as positron emission tomography (PET) in combination with computed tomography (CT) are increasingly being used in biomedical research involving small animal models. The handling of open radioactive substances (radiopharmaceuticals) necessary for PET imaging requires prior official authorization for handling, the application of radiation protection principles, and regular training. The overriding aim of radiation protection is to protect the personnel directly involved, other persons, and the environment from the harmful effects of ionizing radiation.This paper aims to provide an overview of the regulatory requirements of the Radiation Protection Act (StrlSchG), the Radiation Protection Ordinance (StrlSchV), and the associated standards and guidelines. Furthermore, their implementation in practical work in small animal imaging using PET/CT is shown. We will focus on the individual steps of the imaging process, from delivery of the radiopharmaceuticals to waste disposal. This should provide interested researchers with an initial overview of the safe and successful use of the method. In addition, exposure values from the last six years in the literature were analyzed. While personal dosimetric monitoring in clinical PET/CT imaging has been extensively published, there is no published data known to us for personnel for PET/CT research with small animals. The evaluation of the personal dosimetric monitoring of our small animal imaging facility with 7 employees over 4 years revealed an increased personal and finger dose normalized to the injected activity and compared to human PET/CT imaging. Nevertheless, the annual personal dose or annual finger dose in small animal imaging (Hp(10): 1.7 mSv, Hp(0.07): 64 mSv) is lower than for personnel performing human PET/CT imaging at the local University Department of Nuclear Medicine (Hp(10): 3.8 mSv, Hp(0.07): 156 mSv) or published values, and is well below the legally permissible maximum dose of 20 or 500 mSv per year.The increasing use of PET/CT in small animal research can be safely utilized if the radiation protection principles are implemented and continuously trained.