[Statistical parametric mapping analysis of 18F-FDG PET in Parkinson's disease with mild cognitive impairment].

Objective To investigate the characteristics of cerebral metabolism associated with mild cognitive impairment (MCI) Parkinson′s disease (PD), cognitive normal PD and normal control to find a PET biomarker for the diagnose and estimate of PD-MCI. Methods Forty-seven patients diagnosed with PD (included 15 with mild cognitive impairment) and 20 control subjects were enrolled. All the subjects were evaluated with FDG-PET and clinical scale. The statistical parametric mapping (SPM) were analyzed to determine metabolic patterns that may be useful in differentiating between the three groups. Results SPM analysis showed that significant hypometabolism were observed in both side of front lobe, parietal lobe, left temporal lobe and left occipital lobe; in the contrast, the relative hypermetabolism had been observed in the cerebellum, vermis, hippocampus and supplement motor area (SMA) in patients with PD-MCI. PD without MCI showed hypometabolism in both side of front lob, caudate and putamen. PD-MCI showed that the significant hypermetabolism were in the insular and cerebellum while hypometabolism were in the both side of occipital compared to PD without MCI. Conclusion A voxel-by-voxel based SPM method i. e. SPM8 analysis by PET scan is an effective way to analysis the FDG uptake pattern of PD patients. The hypermetabolism in the insula and cerebellum and hypometabolism in the both side of occipital may be a biomarker for make a diagnosis of PD-MCI. Key words: Cognitive impairment; PD; PET