Diagnostic performance of iodine-123-metaiodobenzylguanidine scintigraphy in differential diagnosis between Parkinson's disease and multiple-system atrophy: a systematic review and a meta-analysis.

BACKGROUND AND PURPOSE: This study was designed to review the diagnostic performance of iodine-123-metaiodobenzylguanidine (MIBG) scintigraphy in differential diagnosis between Parkinson's disease (PD) and multiple-system atrophy (MSA). METHODS: A comprehensive computer literature search of studies published through March 2011 regarding MIBG scintigraphy in patients with PD and MSA was performed in PubMed/MEDLINE and Embase databases. Only studies in which MIBG scintigraphy was performed for differential diagnosis between PD and MSA were selected. Pooled sensitivity and specificity of MIBG scintigraphy were presented with a 95% confidence interval (CI). The area under the ROC curve was calculated to measure the accuracy of MIBG scintigraphy in differential diagnosis between PD and MSA. RESULTS: Ultimately, we identified 12 studies comprising a total of 1226 patients (593 patients with PD, 117 patients with other Lewy body disease, 129 patients with MSA, and 387 patients with other diseases). The pooled sensitivity of MIBG scintigraphy to detect PD was 89% (95% CI: 86-91%); the pooled specificity of MIBG scintigraphy to discriminate between PD and MSA was 77% (95% CI: 68-84%). The area under the ROC curve was 0.93. CONCLUSIONS: MIBG scintigraphy is an accurate test for PD detection and differential diagnosis between PD and MSA; this method shows high sensitivity and adequate specificity in this field. Nevertheless, possible causes of false negative and false positive findings should be considered when interpreting the scintigraphic results.