Cardiac MIBG scintigraphy is a sensitive tool for detecting cardiac sympathetic denervation in Parkinson's disease.

[(123)I]Metaiodobenzylguanidine ([(123)I]MIBG) cardiac scintigraphy could be helpful to differentiate Parkinson's disease (PD) from multiple system atrophy (MSA), demonstrating that, in PD with autonomic failure but not in MSA, there is a myocardial postganglionic sympathetic dysfunction. To investigate whether this method is more sensitive than standard autonomic testing to detect early involvement of sympathetic cardiac efferent, we analyse MIBG myocardial uptake in 8 PD patients with normal autonomic testing (nondysautonomia PD group, NDPD) in comparison with 10 PD patients with abnormal autonomic testing (dysautonomia PD group, DPD) and 10 MSA patients. Global MIBG uptake was assessed using the ratio of [(123)I]MIBG uptake in the heart to the upper mediastinum (H/M) on planar scintigraphic data. Regional MIBG uptake was determined on two single photon emission tomography scans in regions of the left ventricle. The mean H/M ratios were significantly different among the three groups (P < 0.0001). H/M ratios of both NDPD and DPD patients groups (H/M = 1.83 +/- 0.50 and 1.24 +/- 0.40, respectively) were significantly lower than in MSA patients (H/M = 2.52 +/- 0.60). However, in NDPD patients, H/M was significantly higher than in DPD patients. When compared to MSA patients, NDPD patients showed a regional reduction in MIBG uptake in all left ventricle regions markedly in the apex and the inferior wall. Our results suggest that MIBG myocardial scintigraphy (analysis of both H/M ratio and regional MIBG uptake) may be more sensitive than standard autonomic testing for the early detection of silent autonomic dysfunction in PD.

Courbon F ，Brefel-Courbon C ，Thalamas C ，Alibelli MJ ，Berry I ，Montastruc JL ，Rascol O ，Senard JM ... -  《MOVEMENT DISORDERS》

Peripheral sympathetic dysfunction in patients with Parkinson's disease without autonomic failure is heart selective and disease specific. taki@med.kanazawa-u.ac.jp.

Taki J ，Nakajima K ，Hwang EH ，Matsunari I ，Komai K ，Yoshita M ，Sakajiri K ，Tonami N ... -  《-》

MIBG scintigraphy for differentiating Parkinson's disease with autonomic dysfunction from Parkinsonism-predominant multiple system atrophy.

Parkinson's disease (PD) with autonomic dysfunction is difficult to differentiate from Parkinsonism-predominant multiple system atrophy (MSA-p). This study aimed to analyze the validity of MIBG scintigraphy for PD with autonomic dysfunction and MSA-p. Thirty-nine patients (PD: 27 patients, MSA-p type: 12) and 12 age-matched controls were prospectively enrolled and underwent MIBG scintigraphy and autonomic function test (AFT). We separately calculated early and delayed heart-to-mediastinal (H/M) ratio and washout rates (WRs). AFT was composed of sympathetic skin reflex and parasympathetic tests based on heart rate variability. Abnormal AFT was observed in 17 (63%) of PD and 10 (83%) of MSA-p. On comparing PD with abnormal AFT with MSA-p, either the early or delayed H/M ratio in PD was not different from that in MSA-p (P > 0.05). Only the WR could differentiate PD with abnormal AFT from MSA-p (47.07 +/- 57.48 vs. 31.39 +/- 31.52, respectively) (P = 0.026). According to the results, WR may be more useful than the early and delayed H/M ratio to distinguish MSA-p from PD with abnormal AFT. Furthermore, the MIBG uptake did not reflect the disease duration or severity.

Chung EJ ，Lee WY ，Yoon WT ，Kim BJ ，Lee GH ... -  《-》

(131)I-MIBG myocardial scintigraphy for differentiation of Parkinson's disease from multiple system atrophy or essential tremor in Chinese population.

Clinical distinction of Parkinson's disease (PD) from multiple system atrophy (MSA) or essential tremor (ET) is sometimes difficult. The purpose of this study was to assess changes in cardiac sympathetic nerve function in PD, MSA, and ET by 131I-MIBG myocardial scintigraphy METHODS: Patients with PD (25), MSA (18), or ET (11) and 10 healthy controls (HC) were enrolled. 131I-MIBG myocardial scintigraphy was performed for each subject, and heart/mediastinum (H/M) ratios were calculated at two sample times (15min and 4h after the injection of 131I-MIBG), representing the 131I-MIBG myocardial uptake ratios. The washout ratio (WOR) of MIBG which indicates the activity tone of the presynaptic sympathetic nerves was calculated for each subject. The H/M ratios at the two sample times (15min and 4h) were 1.65±0.36 and 1.50±0.43 in the PD group, 1.97±0.36 and 2.08±0.57 in the MSA group, 2.34±0.34 and 2.46±0.51 in the ET group, and 2.41±0.26 and 2.66±0.47 in the HC group. The H/M ratios at the two sample times were lower in the PD group than in the MSA, ET, or HC groups, with statistical significance (all P<0.05). The H/M ratios at the two sample times were significantly lower in the MSA group than in the HC group (all P<0.05). There was no significant difference in H/M ratios at either sample time between the ET and HC group (all P>0.05). The washout ratios (WORs) of MIBG were significantly increased in PD group compared with those in MSA, ET and HC groups. In subgroup analysis, The H/M ratios at the two sample times were decreased in early PD group compared with those in early MSA and early ET groups, with statistical significance (all P<0.05). Cardiac sympathetic dysfunction can occur in both PD and MSA patients, especially in PD patients, whereas it remains normal in ET patients. 131I-MIBG myocardial scintigraphy can help distinguish patients with PD from those with MSA or ET with good sensitivity and specificity.

Yang T ，Wang L ，Li Y ，Cheng M ，Jiao J ，Wang Q ，Guo H ... -  《-》

[Cardiac sympathetic dysfunction in Parkinson's disease--relationship between results of 123I-MIBG scintigraphy and autonomic nervous function evaluated by the Valsalva maneuver].

Oka H ，Yoshioka M ，Morita M ，Mochio S ，Inoue K ... -  《-》