Radiation Safety aspects of preclinical PET imaging using clinical PET systems

Objectives: Currently most preclinical PET imaging is performed in dedicated preclinical laboratories that utilize only micro imaging systems. Due to the increased sensitivity and resolution associated with next generation digital PET technology as well as capabilities for high-throughput, preclinical imaging is moving beyond the animal laboratories and into specialized clinical environments. Although cost effective and directly translational, the shift of preclinical imaging on to a clinical PET system results in increased regulatory burden with respect to both radiation safety (RS) and biosafety (BS). Surprisingly to some, the use of radioactive material (RAM) in animals has different and more stringent regulations than the use of RAM in patients. The aims of this exhibit are: 1. Highlight RS regulatory requirements related to animal transport, facility barriers, animal containment, physical shielding, and injection of RAM in animals at a clinical facility. 2. Discuss biosafety and personal dosimetry as well as staff training, access and proximity to PET tracers. 3. Summarize animal care issues related to anesthesia, control, and monitoring using clinical systems. 4. Provide a step-by-step check list to help transition preclinical imaging into a clinical PET environment. All regulatory aspects will be described from the RAM permit/license, institution animal use committee (IACUC) protocols, training records and EHS issues, ordering of RAM, monitoring RAM waste, surveying use locations, and contamination and clean-up policies.

Methods: All regulatory RS aspects described are based directly from our experience of expanding our preclinical imaging focus from our micro imaging animal laboratory to our clinical next generation digital PET/CT system (Vereos, Philips). The instrument is located in a specialized environment credentialed for both human and veterinary patients and research subjects. Our animal facility is located approximately 1 mile from the facility; therefore, transport of animals is required. The radiotracers used are produced at our cyclotron facility approximately 0.5 miles away (¹⁸F, ¹¹C, ¹²⁴I, etc.). We have currently used our clinical dPET/CT system for the preclinical imaging of mice (high throughput simultaneous 18F imaging), canine (¹⁸F, 11C), and NHPs (¹²⁴I).

Results: Although the regulatory requirements associated with performing preclinical PET imaging using a clinical system are broad, the benefits associated with access to leading edge imaging technology, higher throughput, improved image processing capabilities and direct clinical translatability are worth the effort. Careful planning and knowledge of regulatory RS, RB and institutional policy are required in order to allow for a successful expansion. We found that a preclinical checklist to be used in the planning phase of each animal study ensures that all regulatory aspects are met prior to study start. Staff training and awareness is also critical to ensure the safety and welfare of not only the animals but also the staff and patients that use the facility after a study is complete.

Conclusion: Radiation Safety procedures for preclinical PET imaging using clinical PET systems need and can be developed to enable a safe and effective translational imaging, however rigorous planning and coordination with all stakeholders is essential. Research Support: ODSA TECH 13-060 (IPP), TECH 09-028 (OIRAIN), NIBIB R01EB022134