Historically, progress in nuclear medicine has been made by the integrated development of scanners, radioactive tracers and analyzing technology, the three elements to which we have devoted ourselves.
Scanners
Up until the first half of the 2010’s, we had worked in collaboration with Hitachi Ltd. in the development of a PET scanner with semiconductor detectors for the head. Compared with a traditional PET, the semiconductor PET had higher spatial resolution, capable of imaging a smaller lesion, but was not sensitive enough to gamma-rays (511 keV) for PET. Mainstream technology has shifted recently to a combination of scintillator and silicon photomultiplier tube. This idea was embodied in Vereos® developed by Phillips, which we introduced immediately into our research. We are also interested in the use of latest image reconstruction technology to obtain equivalent images using less radioactive tracers/radiation.
Radioactive Tracers
Although FDG is highly useful in various malignant and nonmalignant diseases, it has limitations in diagnosing brain tumors. We embarked on National Program of Advanced Medical Care B, aiming at coverage of C-11 methionine by health insurance. We studied F-18 fluoromisonidazole (FMISO) for research in diagnosing hypoxia of brain tumors, head and neck cancer, lung cancer and cardiac sarcoidosis. Our joint R&D with Nihon Medi-Physics produced F-18 DiFA, a new compound to image hypoxia conducted a first-in-human and patient studies. Other traces we have investigated include C-11 hydroxyephedrine and I-123 IIMU.
Analyzing Method
We are engaged in research into artificial intelligence (AI), particularly deep learning, which is attracting attention recently. We have recently developed a system that predicts the sex, age and body weight from images to prevent patient misidentification. We are developing AIs to predict malignant findings from FDG PET-CT and to diagnose cardiac sarcoidosis. In addition to deep learning, we have published research findings in radiomics.