PRESERVED PONTINE GLUCOSE-METABOLISM IN ALZHEIMER-DISEASE - A REFERENCE REGION FOR FUNCTIONAL BRAIN IMAGE (PET) ANALYSIS

Objective: Our goal was to examine regional preservation of energy metabolism in Alzheimer disease (AD) and to evaluate effects of PET data normalization to reference regions. Materials and Methods: Regional metabolic rates in the pens, thalamus, putamen, sensorimotor cortex, visual cortex, and cerebellum (reference regions) were determined stereotaxically and examined in 37 patients with probable AD and 22 normal controls based on quantitative (18)FDG-PET measurements. Following normalization of metabolic rates of the parietotemporal association cortex and whole brain to each reference region, distinctions of the two groups were assessed. Results: The pens showed the best preservation of glucose metabolism in AD, Other reference regions showed relatively preserved metabolism compared with the parietotemporal association cortex and whole brain, but had significant metabolic reduction. Data normalization to the pens not only enhanced statistical significance of metabolic reduction in the parietotemporal association cortex, but also preserved the presence of global cerebral metabolic reduction indicated in analysis of the quantitative data. Conclusion: Energy metabolism in the pens in probable AD is well preserved, The pens is a reliable reference for data normalization and will enhance diagnostic accuracy and efficiency of quantitative and nonquantitative functional brain imaging.