[PET study using 6-[18F]-fluorodopa in Parkinson's disease]

6-[18F]-fluorodopa (FDOPA) was developed as an analogue of L-DOPA across the blood-brain-barrier and to carry into nigrostriatal dopaminergic neurons. PET study using FDOPA revealed presynaptic dopaminergic function in the striatum of nigrostriatal system of the human brain and many studies have performed to clarify the pathogenesis of Parkinson's disease. FDOPA is also an efficient tracer to analyze pharmacokinetics of L-DOPA by measuring radioactivities of its metabolites in the peripheral blood by HPLC and to evaluate pharmacological effects on dopamine metabolism by pretreatment of dopa decarboxylase inhibitor or COMT inhibitor. PET study using FDOPA is useful not only to diagnose Parkinson's disease but also to differentiate from parkinsonism in combination with other radioactive ligands and with other neuroimaging methods such as MRI.