Abstract: Background  ¹³¹I-metaiodobenzylguanidine (¹³¹I-MIBG) can be intaked by cardiac sympathetic postganglionic fibre, thus becomes the imaging agent to evaluate cardiac sympathetic nerve function. The aim of this study is to investigate the autonomic nerve dysfunction of patients with multiple system atrophy (MSA) by using cardiac ¹³¹I-MIBG scintigraphy.  Methods  Clinical data of 12 MSA patients conforming to the "secord consensus statement on the diagnosis of MSA" was analyzed by Unified Multiple System Atrophy Rating Scale (UMSARS). ¹³¹I-MIBG scintigraphy was performed in 12 MSA patients and 7 age-matched controls. Planar images of the chest were obtained 15 min, 4 h and 24 h after the intravenous injection of 3 mCi 13¹³¹I-MIBG. Cardiac ¹³¹I-MIBG uptake was quantified by comparing region of interest (ROI) over heart/mediastinum (H/M) ratio.  Results  Cardiac 131¹³¹I-MIBG uptake ratio in MSA group was significantly less than that in control group in 15 min (1.90 ± 0.41 vs 2.38 ± 0.32, P = 0.017) and 4 h (1.96 ± 0.63 vs 2.60 ± 0.55, P = 0.039). There were significant difference (P < 0.05) between MSA group and control group.  Conclusions  Cardiac ¹³¹I-MIBG uptake ratio in MSA group was less than that in control group. This finding suggests cardiac sympathetic degeneration may occur in MSA patients.

Key words: Multiple system atrophy, Sympathetic nervous system,  ¹³¹I-MIBG (not in MeSH)

摘要： 研究背景 ¹³¹I-间碘苄胍（¹³¹I-MIBG）可被心脏交感神经节后纤维摄取，是评价心脏交感神经功能的显像剂。本研究采用¹³¹I-MIBG 心肌显像方法，探讨多系统萎缩患者自主神经功能障碍。方法 共12 例符合2008 年第2 版诊断标准的多系统萎缩患者和7 例正常对照者，通过统一多系统萎缩评价量表进行病情严重程度评价，静脉注射¹³¹I-MIBG 3 mCi后于不同测量时间点（15 min、4 h 和24 h）采集胸部前位平面像，计算¹³¹I-MIBG 心肌摄取率。结果 注射¹³¹I-MIBG 后15 min 和4 h，多系统萎缩组患者¹³¹I-MIBG 心肌摄取率均低于正常对照组（15 min：1.90 ± 0.41 对2.38 ± 0.32，P = 0.017；4 h：1.96 ± 0.63 对2.60 ± 0.55，P = 0.039）。结论 多系统萎缩组患者¹³¹I-MIBG 心肌摄取率低于正常对照组，提示多系统萎缩可以发生心脏交感神经变性。

关键词: 多系统萎缩, 交感神经系统, ¹³¹I-间碘苄胍（非MeSH 词）