Kinetic modeling with total body PET-current status and future applications.

Total-body and long axial field-of-view (LAFOV) PET/CT systems have transformed kinetic modeling from a regional research tool into a whole-body quantitative imaging approach. Unlike static SUV-based imaging, kinetic analysis provides physiologically meaningful parameters describing tracer transport, metabolism, and receptor binding. Historically limited by short axial coverage and low sensitivity, dynamic PET studies were confined to single organs and required invasive arterial sampling. LAFOV scanners, offering axial coverage of up to 2 m and >10-fold sensitivity gains, enable simultaneous multi-organ dynamic acquisitions in a single bed position. This facilitates image-derived input functions, shortened protocols, and ultra-low-dose imaging while maintaining quantitative accuracy. Applications span oncology, neurology, cardiology, infection, and inflammation, with emerging roles in healthy volunteer studies and systemic physiology research. AI-driven methods further enhance feasibility by reducing scan duration, improving parametric image generation, and automating motion correction. Despite challenges in workflow standardization and model selection, advances in acquisition protocols and computational tools position LAFOV PET kinetic modeling as a clinically viable technique. Future developments promise integration into routine practice, enabling precision diagnostics, longitudinal monitoring, and novel tracer evaluation. LAFOV PET thus represents a paradigm shift toward comprehensive, whole-body quantitative imaging in nuclear medicine.