BACKGROUND Differential diagnosis between Parkinson's disease (PD) and atypical Parkinsonian syndromes (APS), such as multiple system atrophy (MSA) and progressive supranuclear palsy (PSP), is often difficult because of overlap of common clinical features. We evaluated R2 Blink Reflex Recovery Cycle (R2BRRC) in drug-naive PD patients and in MSA and PSP patients to differentiate early PD from APS. METHODS We investigated 43 patients: 15 drug-naive PD patients, 16 MSA patients, and 12 PSP patients. R2BRRC was evaluated bilaterally at interstimulus intervals (ISIs) of 100, 150, 200, 300, 400, 500, and 750 ms. An asymmetry index (AI) of R2BRRC for each ISI was computed. RESULTS R2BRRC of PD patients showed an increased brainstem excitability for less affected side (LAS) stimulation at ISIs of 100, 150, 200 (p < 0.001), and 300 ms (p = 0.03) compared to more affected side (MAS) stimulation, whereas no differences between LAS and MAS stimulation were found in APS. AI of 0.87 at ISI of 100 ms differentiated PD from MSA with a sensitivity of 86.7% and a specificity of 100%, whereas AI of 0.78 at ISI of 100 ms permitted to discriminate PD from PSP with a sensitivity of 86.7% and a specificity of 91.7%. CONCLUSION AI of R2BRRC may represent a reliable tool in differentiating PD from APS, especially at the early stage of the disease.

中文翻译：

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眨眼反射恢复周期的不对称指数将帕金森氏病与非典型帕金森氏综合征区分开来。

背景技术由于常见临床特征的重叠，通常难以对帕金森氏病（PD）和非典型帕金森氏综合征（APS）（例如多系统萎缩症（MSA）和进行性核上性麻痹（PSP））进行鉴别诊断。我们评估了未经药物治疗的PD患者以及MSA和PSP患者的R2眨眼反射恢复周期（R2BRRC），以区分早期PD和APS。方法我们调查了43例患者：15例未经药物治疗的PD患者，16例MSA患者和12例PSP患者。R2BRRC在100、150、200、300、400、500和750 ms的刺激间隔（ISI）上进行了双边评估。计算了每个ISI的R2BRRC的不对称指数（AI）。结果PD患者的R2BRRC在100、150、200（p <0.001）和300 ms（p = 0）的ISI时显示出对较少受影响的一侧（LAS）刺激的脑干兴奋性增加。03）与受影响的一侧（MAS）刺激相比，而在APS中未发现LAS和MAS刺激之间存在差异。ISI为100 ms时AI为0.87，PD与MSA的区别为敏感性为86.7％，特异性为100％，而ISI为100 ms时AI为0.78，可以将PD与PSP区别开，敏感性为86.7％，特异性为PSP。 91.7％。结论R2BRRC的AI可能是区分PD和APS的可靠工具，尤其是在疾病早期。7％。结论R2BRRC的AI可能是区分PD和APS的可靠工具，尤其是在疾病早期。7％。结论R2BRRC的AI可能是区分PD和APS的可靠工具，尤其是在疾病早期。