HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH RSS TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Figures Only Full Text Full Text (PDF) All Versions of this Article: jnumed.109.065870v1 50/10/1638    most recent Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Related articles in JNM Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Google Scholar Articles by Lim, S. M. Articles by Rowe, C. C. PubMed PubMed Citation Articles by Lim, S. M. Articles by Rowe, C. C.

The ¹⁸F-FDG PET Cingulate Island Sign and Comparison to ¹²³I-β-CIT SPECT for Diagnosis of Dementia with Lewy Bodies

¹ Department of Nuclear Medicine and Centre for PET, Austin Health, Victoria, Australia; ² Australian Nuclear Science and Technology Organization, Menai, New South Wales, Australia; ³ Department of Medicine, Austin Health, University of Melbourne, Victoria, Australia; ⁴ Department of Clinical Neuropsychology, Austin Health, University of Melbourne, Victoria, Australia; ⁵ Department of Aged Care, Austin Health, Victoria, Australia; and ⁶ Department of Psychiatry, Austin Health, Victoria, Australia

Correspondence: For correspondence or reprints contact: Christopher C. Rowe, Centre for PET, Austin Health, 145 Studley Rd., Heidelberg, Victoria 3084, Australia. E-mail: christopher.rowe{at}austin.org.au

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.

Key Words: dementia with Lewy bodies • emission tomography • ¹⁸F-FDG • ¹²³I-β-CIT

COPYRIGHT © 2009 by the Society of Nuclear Medicine, Inc.

Related articles in JNM:

This Month in JNM

JNM 2009 50: 11A-12A. [Full Text]