The radiopharmaceutical 6-fluoro-(18F)-L-3,4-dihydroxyphenylalanine (FDOPA) has been proposed since 1986 in cognitive research on physiology and physiopathology of DOPA distribution in the human brain, and also for clinical purposes in neurology and oncology.  PET with FDOPA, provides a functional approach of pathologies, organs or tissues where enhanced intracellular transport and decarboxylation of the amino acid dihydroxyphenylalanine is the diagnostic target.

6-fluoro(18F)-L-dopa crosses the blood-brain barrier; therefore, when injected into the blood stream, it reaches the dopaminergic cells in the brain and is used by the brain as a precursor for dopamine. This makes it possible to monitor intracerebral synthesis and uptake of dopamine by means of the positron-emitting 6-fluoro(18F)-L-3,4-dihydroxyphenylalanine (FDOPA), in conjunction with externally-placed devices suited for detection of annihilation photons, which progressively led to the most recent positron emission tomography (PET) units.