Background: 123I-metaiodobenzylguanidine (123I-MIBG) myocardial scintigraphy is clinically used to estimate myocardial sympathetic damage in some forms of heart disease, autonomic nerve disturbance in diabetic neuropathy, and disturbance of the autonomic nervous system in neurodegenerative disease. In the present study, examinations were performed to clarify the rate and characteristics of cardiac sympathetic disturbance in Parkinson's disease (PD) and usefulness of 123I-MIBG myocardial scintigraphy to differentiate PD from the Lewy Body Disease (LBD).
Material and methods: 108 subjects were studied. There were 70 patients with PD, 21 patients with LBD, and 17 age-matched normal subjects without neurological disease. The clinical parameters evaluated were severity of the process (measured by Hoehn and Yahr Scale), vegetative manifestations, development time and use of medication taken. Myocardial adrenergic function was analyzed by imaging with 123I-MIBG. Early (15 min) and delayed (4 h) images of the thorax in the anterior view were obtained after injection of 123I-MIBG (111 MBq). The qualitative and semiquantitative 123I-MIBG uptake was quantified by calculating a heart-to-mediastinum ratio (HMR) and analyzed in a blind manner.
Results: The mean H/M ratio in patients with PD and LBD was significantly lower than in controls (p < 0.05). This is independent of development time, process severity, use of medication or vegetative manifestations. The HMR obtained in LBD patients is less clear than in PD.
Conclusion: 123I-MIBG myocardial scintigraphy might detect early disturbances of the sympathetic nervous system in PD and LBD.