Comparison of the usefulness of brain perfusion SPECT and MIBG myocardial scintigraphy for the diagnosis of dementia with Lewy bodies

Abstract

Background: Supportive features in the diagnostic criteria for dementia with Lewy bodies (DLB) include occipital hypoperfusion and decreased cardiac uptake of (123)I-metaiodobenzylguanidine (MIBG). In this study, we performed both brain perfusion single photon emission computed tomography (SPECT) and MIBG myocardial scintigraphy in the same subjects and evaluated their sensitivity to detect the characteristic features of DLB.

Methods: Twenty-five patients with probable DLB (76.8 +/- 5.1 years old, 10 male) underwent (99m)Tc-ethylcysteinate dimer brain perfusion SPECT and (123)I-MIBG myocardial scintigraphy. The results of SPECT were analyzed using a qualitative analysis program, easy Z score imaging system (eZIS), and an automated quantitative analysis program, 3DSRT.

Results: Qualitative analysis using eZIS demonstrated occipital hypoperfusion in 17 subjects (68%). The quantified mean blood perfusion in the occipital segment on the 3DSRT template was 40.7 +/- 5.03 ml/100 g/min (right) and 40.5 +/- 5.38 ml/100 g/min (left), and in 19 DLB patients these values were below the normal limit. Twenty-four of 25 subjects (96%) had decreased cardiac MIBG uptake in the delayed image.

Conclusion: MIBG myocardial scintigraphy was superior to brain perfusion SPECT in detecting a characteristic feature of DLB. Our results suggest that combining SPECT and MIBG scintigraphy could increase the accuracy of clinical diagnosis of DLB.