Cardiac I-Metaiodobenzylguanidine Scintigraphy in Patients with Parkinson’s Disease and Parkinson’s Disease with Dementia

Background: Because patients with idiopathic Parkinson’s disease (PD) may exhibit patterns of cognitive impairment, it is difficult to distinguish from patients with Parkinson's disease dementia (PDD). Recently, cardiac I-metaiodobenzylguanidine (MIBG) scintigraphy has been used to help distinguish PD from atypical Parkinsonism. This study investigated the relations between cardiac I-MIBG scintigraphy and these diseases. Methods: Cardiac I-MIBG scintigraphy was conducted on 18 patients with PD, 18 patients with PDD and 13 normal controls matched for age, disease duration and severity of symptoms. The heart to mediastinum (H/M) ratio was calculated. Results: The mean values of H/M ratio were significantly lower for PDD and PD than for normal controls but there was no difference between the disease groups. Conclusion: Unfortunately, cardiac I-MIBG scintigraphy did not distinguish PDD from PD in our study. We suggest further research with larger study populations be done to clarify the use of cardiac I-MIBG scintigraphy in differentiating other Lewy body diseases from dementia with PD features.