The objective of this study was to show that the Logan analysis is theoretically more appropriate than the Patlak analysis for the assessment of 6-[18F] fluoro-L-DOPA (FDOPA) positron emission tomography (PET) dynamic data in brain tissue without an irreversible compartment, e.g., occipital cortex. Another purpose was to provide the first application of this analysis to real data. Ten normal controls (NC), 10 Parkinson's disease (PD) patients, and 10 Parkinson's disease with dementia (PDD) patients underwent FDOPA PET. The Logan analysis and the Patlak analysis were applied to the occipital cortex with the cerebellum as a reference tissue. In the occipital cortex, the Logan analysis showed a significant difference (p=0.018) between NC and PDD patients. However, the Patlak analysis showed no significant differences, but larger variances. The Logan analysis of FDOPA PET dynamic data in the occipital cortex was considered to be theoretically appropriate and to provide new insight into the analysis of that region.