Comparison of ¹²³I-MIBG myocardial scintigraphy, brain perfusion SPECT, and voxel-based MRI morphometry for distinguishing between dementia with Lewy bodies and Alzheimer’s disease

Objective: This study aimed to compare the diagnostic value of ¹²³I-metaiodobenzylguanidine (MIBG) myocardial scintigraphy, N-isopropyl-p[¹²³I]iodoamphetamine (IMP) brain perfusion single-photon emission computed tomography (SPECT), and brain magnetic resonance imaging (MRI) voxel-based morphometry (VBM) for the differentiation of dementia with Lewy bodies (DLB) and Alzheimer’s disease (AD).

Methods: Thirty-five and 34 patients with probable DLB and probable AD, respectively, were enrolled. All patients underwent ¹²³I-MIBG myocardial scintigraphy, ¹²³I-IMP brain perfusion SPECT, and brain MRI. For ¹²³I-MIBG imaging, we calculated early and delayed heart-to-mediastinum (H/M) uptake ratios. Three-dimensional stereotactic surface projections (3D-SSP) were used to analyze the results of ¹²³I-IMP SPECT. VBM with statistical parametric mapping 8 plus diffeomorphic anatomical registration using exponentiated Lie algebra (DARTEL) was used to analyze the brain MRI data.

Conclusions: ¹²³I-MIBG myocardial scintigraphy was superior to brain perfusion SPECT and brain MRI using an advanced statistical technique to differentiate DLB and AD.

Results: The area under the receiver operating characteristic curves (AUC) for discriminating DLB and AD was highest (0.882) for the delayed H/M ratio on ¹²³I-MIBG scintigraphy. AUC for z-score measurement in the occipital lobe was 0.818 and that for the extent of gray matter (GM) atrophy in the whole brain was 0.788. AUC for the combination of 3D-SSP and VBM analysis was 0.836. The respective sensitivities and specificities for distinguishing DLB from AD were 97.1 and 100 % for the delayed H/M ratio using ¹²³I-MIBG scintigraphy; 88.6 and 73.5 % for the occipital lobe z-score using 3D-SSP analysis; 85.7 and 64.7 % for the extent of whole brain GM atrophy using voxel-based MRI morphometry; and 91.4 and 76.5 % for the combination of 3D-SSP analysis and VBM.