Initial clinical experience of N13-ammonia myocardial perfusion PET/CT using a compact superconducting production system

Abstract

Although N13-ammonia has favorable properties among FDA approved radiotracers, complexity of implementation has limited its use. We describe the initial patient experience of N13-ammonia PET imaging using a compact N13-ammonia production system. N13 was produced using the ION-12SC, a 12MeV, 10uA superconducting minimally shielded cyclotron, and reduced to N13-ammonia in an automated multi-use purification unit. Patients were power injected with 9.3\u2009±\u20091.1 mCi (344.1\u2009±\u200940.7 MBq) of N13-ammonia for rest imaging, and 18.8\u2009±\u20090.9 mCi (695.6\u2009±\u200933.3 MBq) of N13-ammonia was injected at peak hyperemia for stress testing. Images were interpreted for relative perfusion, left ventricular volumes/function, blood flow quantification, and scored for image quality. In total 97 patients underwent 98 N13-ammonia PET scans (32 rest only/65 rest-stress/1 stress only). Image quality was 91.8% good or excellent. None were poor/non-diagnostic. Study durations were acceptable. Tracer related radiation dosimetry to patients was 0.7\u2009±\u20090.1 mSv (rest only), and 2.1\u2009±\u20090.1 mSv (rest-stress). Clinical N13-ammonia production by the Ionetix ION-12SC delivers high quality myocardial PET perfusion images in a rapid protocol.