Brücke T, Djamshidian S, Bencsits G, Pirker W, Asenbaum S, Podreka I
Neurologische Abteilung Wilhelminenspital, Wien.
J Neurol. 2000 Sep;247 Suppl 4:IV/2-7. doi: 10.1007/pl00007769.
This paper gives an overview of the clinical importance of SPECT and PET imaging of the dopaminergic system in the differential diagnosis and for the determination of the progression rate of Parkinson's disease (PD). D2 receptor imaging can help to differentiate multiple system atrophy (MSA) and progressive supranuclear palsy (PSP) from PD. In patients treated with neuroleptics it is possible to determine the rate of striatal D2 receptor blockade using this technique. This occupancy rate parallels the occurrence of parkinsonian side effects. Its measurement helps in the selection of newer atypical neuroleptics, which can be used to treat drug-induced psychosis in PD because they do not aggravate parkinsonian symptoms. Imaging of dopaminergic neurons with [123I]beta-CIT SPECT or [18F]DOPA PET is a way to visualize and quantify the nigrostriatal dopaminergic lesion in PD. Findings correlate with clinical rating scales and demonstrate the feasibility of detecting the preclinical lesion in patients with hemiparkinson or familial PD. [123I]beta-CIT SPECT can easily distinguish patients with essential tremor and patients with "lower body parkinsonism" due to a subcortical vascular encephalopathy. MSA and PSP cannot be separated from PD with this method alone. Longitudinal studies with [123I]beta-CIT SPECT and [18F]DOPA PET can quantify the progression rate in PD. SPECT results from our own group show a low rate of progression in patients with a long duration of disease and a more marked progression rate in patients with shorter disease duration. In the former group regions in the striatum with higher beta-CIT binding at the time of the first SPECT scan decline faster than regions with lower binding. These findings suggest a curvilinear course of progression which starts at different time points in different striatal regions and which levels off after several years of disease duration. These findings are in line with data from PET studies and underline the importance of an early start of neuroprotective strategies. Preliminary data from PET and SPECT studies in early PD suggest that dopamine agonists might have a slight neuroprotective effect and might slow down the rate of progression of the disease.
本文概述了多巴胺能系统单光子发射计算机断层扫描（SPECT）和正电子发射断层扫描（PET）成像在帕金森病（PD）鉴别诊断及病情进展速率测定方面的临床重要性。D2受体成像有助于将多系统萎缩（MSA）和进行性核上性麻痹（PSP）与PD区分开来。对于使用抗精神病药物治疗的患者，利用该技术能够测定纹状体D2受体的阻断率。这种占有率与帕金森氏症副作用的发生情况平行。其测量有助于选择新型非典型抗精神病药物，这些药物可用于治疗PD患者的药物性精神病，因为它们不会加重帕金森氏症症状。用[123I]β-CIT SPECT或[18F]多巴PET对多巴胺能神经元进行成像，是一种可视化和量化PD中黑质纹状体多巴胺能损伤的方法。研究结果与临床评分量表相关，并证明了在偏侧帕金森病或家族性PD患者中检测临床前损伤的可行性。[123I]β-CIT SPECT能够轻松区分特发性震颤患者和因皮质下血管性脑病导致的“下体帕金森综合征”患者。仅用此方法无法将MSA和PSP与PD区分开来。采用[123I]β-CIT SPECT和[18F]多巴PET进行的纵向研究能够量化PD的病情进展速率。我们团队的SPECT研究结果显示，病程较长的患者病情进展速率较低，而病程较短的患者病情进展速率更为明显。在前一组中，首次SPECT扫描时β-CIT结合较高的纹状体区域下降速度比结合较低的区域更快。这些发现表明病情进展呈曲线状，在不同的纹状体区域始于不同时间点，且在病程数年之后趋于平稳。这些发现与PET研究数据一致，并强调了尽早启动神经保护策略的重要性。早期PD的PET和SPECT研究初步数据表明，多巴胺激动剂可能具有轻微的神经保护作用，并可能减缓疾病的进展速率。
