TY - JOUR T1 - The <sup>18</sup>F-FDG PET Cingulate Island Sign and Comparison to <sup>123</sup>I-β-CIT SPECT for Diagnosis of Dementia with Lewy Bodies JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 1638 LP - 1645 DO - 10.2967/jnumed.109.065870 VL - 50 IS - 10 AU - Seok Ming Lim AU - Andrew Katsifis AU - Victor L. Villemagne AU - Rene Best AU - Gareth Jones AU - Michael Saling AU - Jennifer Bradshaw AU - John Merory AU - Michael Woodward AU - Malcolm Hopwood AU - Christopher C. Rowe Y1 - 2009/10/01 UR - http://jnm.snmjournals.org/content/50/10/1638.abstract N2 - Neuroimaging is increasingly used to supplement the clinical diagnosis of dementia with Lewy bodies (DLB) by showing reduced occipital metabolism and perfusion and reduced striatal dopaminergic innervation. We aimed to optimize the interpretation of 18F-FDG PET images for differentiating DLB from Alzheimer disease (AD) and to compare the results with dopamine transporter imaging using 123I-β-carbomethoxy-3ß-(4-iodophenyl)tropane (123I-β-CIT) SPECT. Methods: Fourteen subjects with a clinical diagnosis of DLB and 10 with AD underwent both 18F-FDG PET and 123I-β-CIT SPECT. Four DLB and 1 AD diagnoses were subsequently confirmed at autopsy. Diagnostic accuracy was calculated for visual interpretation by 3 readers of standard 3-plane and stereotactic surface projection 18F-FDG PET images, receiver-operating-characteristic analysis of regional 18F-FDG uptake, and a cutoff value for the striatal-to-occipital binding ratio of β-CIT defined by receiver-operating-characteristic analysis. Results: Visual interpretation of 3-plane 18F-FDG PET images had a sensitivity of 83% and specificity of 93% for DLB, slightly higher than the results with the stereotactic surface projection images. Regionally, hypometabolism in the lateral occipital cortex had the highest sensitivity (88%), but relative preservation of the mid or posterior cingulate gyrus (cingulate island sign) had the highest specificity (100%). Region-of-interest analysis revealed that occipital hypometabolism and relative preservation of the posterior cingulate both had a sensitivity of 77% and specificity of 80%. β-CIT achieved 100% accuracy and greater effect size than did 18F-FDG PET (Cohen d = 4.1 vs. 1.9). Conclusion: Both 18F-FDG PET and 123I-β-CIT SPECT appear useful for the diagnosis of DLB, although the latter provides more robust results. The cingulate island sign may enhance the specificity of 18F-FDG PET. ER -