Abnormal function of the motor circuit in chorea and dystonia : a comparison with Parkinson's disease.

我们研究了立体定向苍白球和丘脑手术对舞蹈病和肌张力障碍以及内苍白球（GPi）神经元放电模式异常的影响。对11例帕金森病患者在CT引导下采用微电极进行手术治疗（6女5男，49-74岁），1例齿状苍白球路易体萎缩，表现为舞蹈病（例1，女，29岁，双侧苍白球切开术），一位脱肌张力障碍患者（例2，男，54岁，单侧苍白球切开术），原发性全身性肌张力障碍患者（病例3，女性，55岁，单侧苍白球DBS），以及1例全身性肌张力障碍和颅内钙化患者（例4，女，27岁，双侧丘脑DBS）。患者根据AIMS或BPRS进行评估。Elgiloy，玻璃涂层微电极，在1000 Hz下阻抗为0.4 MΩ，用于单细胞记录。手术中未使用镇静剂，所有药物均在手术期间和夜间暂停使用。在标测期间记录GPi的自发单细胞活动的10至30秒样本，并存储在DAT磁带上。在50 kHz下对神经元信号进行数字化处理，根据峰值幅度和窗口孔径大小区分动作电位，计算单细胞动作电位的放电频率、振荡指数和爆发率。例1术后舞蹈症消失，例2术后肌张力障碍消失。例3和例4肌张力障碍改善30- 50%。病例2和病例3中肌张力障碍期间GPi的神经元记录显示，与无肌张力障碍的帕金森病患者的放电模式相比，平均放电率较低，具有高度爆发性和较少振荡性。这些结果表明，舞蹈病和肌张力障碍的结果从基底神经节输出的活动减少，但改变的放电模式是这些运动障碍的病理生理学的一个重要因素。

We studied the effects of stereotactic pallidal and thalamic surgeries on chorea and dystonia and abnormality of the neuronal firing pattern of the internal globus pallidus (GPi). The surgery was performed using microelectrode and CT guiding in 11 parkinsonian patients (6 females and 5 males, 49-74 years old), a patient with dentate-pallidoluysian atrophy showing chorea (Case 1, female, 29 years old, bilateral pallidotomy), a patient with off-dystonia (Case 2, male, 54 years old, unilateral pallidotomy), a patient with primary generalized dystonia (Case 3, female, 55 years old, unilateral pallidal DBS), and a patient with generalized dystonia and intracranial calcification (Case 4, female, 27 years old, bilateral thalamic DBS). Patients were evaluated according to the UPDRS or AIMS. Elgiloy, glass-coated microelectrodes with an impedance of 0.4 MΩ at 1000Hz were used for single-cell recording. No sedation was used in surgery, and all medication was withheld overnight and during surgery. Ten-to 30-second samples of spontaneous single-cell activity from GPi were recorded during mapping and stored on DAT tape. Neuronal signals were digitized at 50kHz, action potentials were discriminated according to the peak amplitude and window aperture onscreen, and the firing rates, oscillation indexes and burst ratios of single-cell action potentials were calculated. Chorea in Case 1 and dystonia in Case 2 were disappeared after surgery. Dystonia in Case 3 and Case 4 was improved by 30-50%. Neuronal recording from GPi during dystonia in Case 2 and Case 3 revealed that the mean firing rates were low, highly bursty and less oscillatory, as compared with firing patterns in off-state parkinsonian patients without dystonia. These results suggest that chorea and dystonia results from the decreased activities of the basal ganglia output, but the altered firing pattern is a significant factor underlying pathophysiology of these movement disorders.