TY - JOUR T1 - Initial Clinical Comparison of <sup>18</sup>F-Florbetapir and <sup>18</sup>F-FDG PET in Patients with Alzheimer Disease and Controls JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 902 LP - 907 DO - 10.2967/jnumed.111.099606 VL - 53 IS - 6 AU - Andrew B. Newberg AU - Steven E. Arnold AU - Nancy Wintering AU - Barry W. Rovner AU - Abass Alavi Y1 - 2012/06/01 UR - http://jnm.snmjournals.org/content/53/6/902.abstract N2 - The purpose of this study was to determine how clinical interpretations of the 18F-amyloid tracer florbetapir compares diagnostically with 18F-FDG PET when evaluating patients with Alzheimer disease (AD) and controls. Methods: Nineteen patients with a clinical diagnosis of AD and 21 elderly controls were evaluated with both 18F-florbetapir and 18F-FDG PET scans. Scans were interpreted together by 2 expert readers masked to any case information and were assessed for tracer binding patterns consistent with AD. The criteria for interpreting the 18F-florbetapir scan as positive for AD was the presence of binding in the cortical regions relative to the cerebellum. 18F-FDG PET scans were interpreted as positive if they displayed the classic pattern of hypometabolism in the temporoparietal regions. Scans were interpreted as either positive or negative for AD. In addition, a relative scoring system was used to assess the degree of either hypometabolism or amyloid binding in specified regions. The metabolism and amyloid binding scores for each region were compared across subjects. An overall ratio was calculated on the basis of values in regions expected to be affected by AD and those not expected to be affected. The metabolic ratio and amyloid ratio were then correlated with the mini-mental status examination (MMSE) score. Results: The sensitivity and specificity, compared with the clinical diagnosis of AD or controls, for the 18F-florbetapir scans were 95% and 95%, respectively, and for the 18F-FDG scans 89% and 86%, respectively. When a comparison with MMSE scores was made, 18F-FDG significantly correlated with MMSE when both controls and AD patients were included (r = 0.79, P &lt; 0.0001) and in AD patients alone (r = 0.70, P = 0.001). The 18F-florbetapir scores significantly correlated with MMSE scores only when both controls and AD patients were included (r = 0.62, P &lt; 0.001) but not in the AD group alone (r = 0.12, P = 0.66). Conclusion: Overall, both scans performed well in detecting AD in patients with known clinical AD. Both scans correlated well with cognitive status as determined by MMSE when the entire cohort of controls and AD patients was evaluated. However, only the 18F-FDG scans correlated with cognitive status when AD patients were evaluated separately. ER -