Evaluation of metabolic changes in Parkinson's disease patients with different severities of cognitive impairments by 18F-FDG PET/CT brain imaging / 中华核医学与分子影像杂志

ABSTRACT

Objective To investigate the characteristics of cerebral glucose metabolism (CGM) in PD patients with cognitive impairment (PD-CI) using 18F-FDG PET/CT,and to analyze the correlation between the progress of PD-CI and CGM changes.Methods A total of 31 idiopathic PD patients (14 males,17 females,aged 37-77 years) from May 2013 to February 2014 were divided into 3 groups based on Montreal cognitive assessment (MOCA):none CI in PD (PD-NC) group (MOCA＞26 scores),mild CI in PD (PD-MCI) group (MOCA 21-26 scores),PD with dementia (PDD) group (MOCA＜21 scores).The normal controls (NC) group included 12 age-and gender-matched healthy adults (7 males,5 females,aged 40-76 years).All subjects underwent PET/CT imaging after intravenous injection of 18F-FDG(5.55 MBq/kg).MIMneuro software was used to analyze the data.The correlation between the CGM and cognitive function was analyzed using Pearson or Spearman correlation analysis.Results (1) Compared with NC group,PDD group presented a widespread cortical metabolism decrease in frontal,parietal,temporal,occipital 19bes and the limbic lobe;PD-MCI group showed hypometabolic areas in the parietal and occipital lobes,and with less extent in the frontal and temporal lobes;PD-NC group showed no significant cerebral hypometabolism.(2) Compared with PD-NC group,PDD group showed widespread cortical metabolism decrease in occipital lobe,temporal lobe,partial parietal cortex and the posterior cingulated cortex.Compared with PD-MCI group,PDD group had lower metabolism,mainly in posterior brain areas (parietal,occipital and temporal lobes).Compared with PD-NC group,PD-MCI group showed hypometabolism in right supramarginal gyrus and the left parahippocampal gyrus.(3) There were positive correlations between visuospatiaL/executive function and visual cortex metabolism,angular gyrus metabolism or superior parietal lobule metabolism (r =0.535,0.443,0.395;all P＜0.05).A positive correlation was also found between delayed memory and heschl's gyrus metabolism (r=0.337,P＜0.05).Conclusions The cerebral glucose metabolism detected with 18F-FDG PET/CT is well correlated with MOCA assessments.Thus it may be helpful in evaluation of the progress of cognitive impairments in PD.