Characteristics of cerebral glucose metabolism in patients with corticobasal degeneration

Objective To identify abnormal cerebral glucose metabolism characteristics in patients with corticobasal degeneration (CBD) using 18F-fluorodeoxyglucose (FDG) PET imaging. Methods From January 2014 to January 2017, resting-state brain 18F-FDG PET imaging was performed in 10 CBD patients (5 males, 5 females; average age: (63.4±6.2) years) and 20 age-matched healthy subjects (8 males, 12 female; average age: (63.6±6.2) years). Voxel-based statistical parametric mapping (SPM) was used to analyze images to obtain the CBD-related brain metabolic characteristics. The regional cerebral metabolic rate of glucose (rCMRglc) was compared between 2 groups by two-sample t test. Results Compared with healthy controls, CBD group demonstrated asymmetrically decreased glucose metabolism mainly in the cerebral hemisphere opposite to the more clinically affected body side, including the superior, middle and inferior frontal gyrus, the precentral gyrus, the superior and inferior parietal lobule, the angular gyrus, the supramarginal gyrus, the precuneus, the middle occipital gyrus, the middle and inferior temporal gyrus, Heschl gyrus, the fusiform gyrus, the insula and the thalamus. And relatively increased glucose metabolism was present in ipsilateral precentral and postcentral gyrus, hippocampus, insula and putamen, bilateral cerebellum, paracentral lobules and pontine. The rCMRglc in those regions was significantly different between CBD patients and healthy controls (t values: 4.236-9.044, all P<0.01). Conclusion The asymmetric cerebral glucose metabolism features in CBD based on 18F-FDG PET imaging contribute to the differential diagnosis between CBD patients and healthy subjects. Key words: Cerebral cortex; Basal ganglia diseases; Nerve degeneration; Positron-emission tomography; Deoxyglucose