脑深部电刺激术的电极移位

目的研究脑深部电刺激术(DBS)电极移位的原因及预防措施.方法研究113例帕金森病DBS术中及术后程控时的深部电极与预置靶点的差异.结果发生电极移位5例,其中术中发生2例;3例术中刺激效果满意,电极未发生移位,但术后4周程控时达不到满意效果,复查头颅MRI示脑深部电极移位,2例比原定位置深4 mm,1例比原定位置深6 mm.结论植入的刺激电极在颅内移位是影响DBS治疗效果的重要因素,可造成某些病人术中刺激效果好,但一段时间后疗效差的现象,应积极预防.     

滑轨CT在帕金森病患者脑深部电刺激手术中的应用价值

目的评价滑轨CT在帕金森病(PD)患者脑深部电刺激(DBS)手术中的临床应用效果。方法选择郑州大学第一附属医院神经外科自2019年5月至2023年5月采用DBS手术治疗的117例PD患者, 其中采用局麻46例, 全麻71例;73例患者行双侧丘脑底核(STN)DBS手术, 43例患者行双侧苍白球内侧部(GPi)DBS手术, 1例患者行右侧GPi DBS、左侧STN DBS手术。通过术前/术中滑轨CT图像与术前MRI图像融合, 计算患者术前计划靶点与术中实际靶点的空间距离(如空间距离大于2 mm, 表示电极位置偏移, 及时调整电极位置)。比较不同麻醉、手术方式患者术前计划靶点与术中实际靶点空间距离的差异。结果 117例PD患者手术均顺利完成, 共植入234根电极。无因电极错位或疗效欠佳行二次手术的患者。CT扫描期间未发生麻醉脱管及机械碰撞, 无颅内出血并发症。117例患者术前计划靶点与术中实际靶点的空间距离为(1.35±0.50) mm。术中4根电极的位置明显偏移, 术中即刻调整电极位置, 再次复查CT证实电极位置良好。全麻组和局麻组、STN组和GPi组患者双侧术前计划靶点与术中实际靶点空...     

微电极记录与影像技术联合应用对帕金森病脑深部电刺激最佳刺激治疗位置的研究

目的探讨帕金森病(PD)患者脑深部电刺激(DBS)术最佳刺激靶点的位置。方法 40例PD患者接受立体定向双侧丘脑底核(STN)脑深部电刺激术。术中通过微电极记录采集神经元电活动,埋置脑深部电刺激器,术后复查电极位置,通过影像资料和电生理数据,确定电极尖端坐标,并计算电极各触点坐标,以及电极针道中STN上下边界和中心点的坐标。结果最佳刺激触点中心坐标的平均位置与STN上边界坐标的平均位置的差异无统计学意义。结论 STN上边界区域为DBS治疗PD的最佳刺激位置。     

基于电极偏差的靶点矫正法在脑深部电刺激术中的初步临床应用

目的探讨基于电极偏差的靶点矫正法在脑深部电刺激术(DBS)中对提高电极植入精确性的临床应用价值。方法回顾性分析2014年3月至2018年4月浙江大学医学院附属第二医院神经外科行丘脑底核DBS治疗的61例帕金森病患者的临床资料。其中,2014年3月至2017年3月应用DBS治疗患者42例(84侧电极),为未矫正组,术后进行头颅MRI与CT融合并应用公式分别计算电极在X、Y、Z轴的偏差距离以及电极偏差值ΔP,并制定相应的靶点矫正规则;2017年4月至2018年4月纳入的19例患者(36侧电极)均参照此矫正规则进行靶点矫正,再行DBS治疗,为矫正组,术后复查头颅CT,并进行头颅MRI与CT融合后计算ΔP。将电极偏差程度按照ΔP≤1 mm、>1~2 mm、>2~3 mm和>3 mm进行划分。将电极植入靶点后无需术中调整定义为第1次穿刺成功。比较两组患者电极第1次穿刺成功率、ΔP以及电极偏差程度。结果两组患者手术均顺利完成,术后无致残、死亡等严重并发症,术后复查头颅CT结果均未见脑梗死或脑出血。未矫正组左侧ΔP为(1.6±0.9)mm,其中X轴向内移(0.1±0.9)mm,Y轴向后移(1.0±0.9)mm,Z轴向上移(0.5±0.5)mm;右侧ΔP中位数(上、下四分位数)为1.4(1.2,2.2)mm,其中X轴向内移(0.2±0.9)mm,Y轴向后移1.0(0.3,1.5)mm,Z轴向上移(0.4±0.5)mm,计算所得的靶点矫正规则为双侧Y轴向均向前增加1.0 mm,双侧Z轴向均向下增加0.5 mm。矫正组术中电极第1次穿刺成功率为94.4%(34/36),与未矫正组的77.4%(65/84)比较,差异有统计学意义(χ²=5.082,P=0.024)。矫正组的左侧ΔP较未矫正组减小(t=-3.507,P=0.001);但矫正组的右侧ΔP与未矫正组比较,差异无统计学意义(Z=-1.646,P=0.100)。矫正组与未矫正组比较,双侧电极偏差程度的差异均具有统计学意义(均P<0.05)。结论基于电极偏差的靶点矫正法可提高术中电极第1次穿刺成功率,减小电极位置的偏差,对提高DBS电极植入精确性有一定的临床应用价值。     

立体定向框架下帕金森病脑深部电刺激手术标准化流程的思考与改进

目的探讨立体定向框架下帕金森病脑深部电刺激(DBS)手术标准化流程的细节及其改进措施。方法回顾分析2016年1月—2018年12月南京医科大学附属脑科医院神经内、外科联合评估后,行DBS治疗的236例中晚期帕金森病患者的临床资料。其中2例为单侧DBS,其余均为双侧,共470侧;术中采用改进后的手术流程,并关注手术细节;术后影像复查与手术计划对比,分析实际电极位置与计划的误差。结果本组患者最佳电极触点位置与计划位置相差(0. 74±0. 19) mm。术后发生皮层少量无症状出血者1例,≥30 mL的颅内积气者3例。结论帕金森病DBS手术需要高度精细化,在每一个环节与细节应给予足够的注意与精细化的操作,才能提高电极植入的精确度。     

脑深部电刺激术的手术并发症及防治

目的 探讨脑深部电极刺激术(DBS)手术并发症的产生原因及防治方法.方法 对278例(531侧)接受DBS治疗的患者发生的手术并发症及其处理方法进行回顾性分析.结果 DBS手术并发症的发生主要与手术操作、治疗靶点的选择与定位、刺激器装置等方面有关.其中与手术相关的并发症为脑内血肿、术后癫痫、脑脊液漏等;与刺激靶点选择和定佗相关的并发症有异动症、构音障碍、眼睑下垂等;与植入装置相关的并发症有电极折断、电极移位、装置故障等.结论 严格与细致的手术操作、选择正确的手术方式、精细的术后程控可有效地减少和预防DBS手术并发症的发生.     

脑深部电刺激术同期植入两侧电极精度的对比研究

目的探讨脑深部电刺激(DBS)术同期植入两侧电极的精度差异。方法收集北部战区总医院神经外科2017年2月—2019年2月行同期双侧DBS术患者133例。在ROSA机器人辅助下共植入电极266侧,其中丘脑底核(STN) 160侧、丘脑腹中间核(nucleus ventralis intermedius,Vim) 2侧、苍白球内侧部(Gpi) 104侧。所有患者均于术后2 h和术后1周复查头部CT三维重建,并与术前CT图像(手术计划靶点)融合;测量植入电极与计划靶点在靶点平面X轴和Y轴上的误差距离。结果全部266根治疗电极均成功植入,未发生颅内出血、颅内感染和偏瘫等严重并发症,也未出现电极折断现象。术后2 h和术后1周时,第一侧与第二侧植入电极在X轴与Y轴上的误差比较,差异均无统计学意义(均P 0. 05)。结论 ROSA机器人辅助下DBS术同期植入两侧电极的精度无明显差异。DBS术可以同时植入双侧治疗电极,无需延期手术植入第二侧电极。     

ROSA辅助脑深部电刺激术的精准性研究

目的探讨立体定向手术机器人(Robot of Stereotactic Assistant,ROSA)辅助下脑深部电刺激术(DBS)准确性及安全性。方法 18例帕金森病和2例特发性震颤病人,均行ROSA辅助下DBS,术后复查CT,记录电极在x轴和y轴最大偏差距离和最小偏差距离,计算平均值。记录术中电极相关出血事件与术后并发症。结果 20例病人术前计划植入电极39根,实际植入电极39根,其中植入丘脑底核37根,丘脑腹中间核2根。电极尖端距靶点x轴最大偏差距离2.13 mm,最小偏差距离0.09 mm,平均偏差距离(0.68±0.43)mm;y轴最大偏差距离1.50 mm,最小偏差距离0.21 mm,平均偏差距离(0.63±0.29)mm。结论 ROSA辅助下行DBS,电极植入准确,安全性高。     

经颅超声在STN-DBS电极植入术靶点定位中的应用

目的 探讨经颅超声引导技术在丘脑底核（STN）脑深部电刺激术（DBS）中植入电极精准定位中的应用价值。方法 回顾性分析2020年5月至2021年5月利用经颅超声引导技术辅助丘脑底核（subthalamic nucleus STN）-DBS治疗的11例运动障碍性疾病的临床资料。在接受STN-DBS电极植入侧有合适颞骨窗时经颅超声对电极位置进行监测和测量。结果 11例中,帕金森病9例,肌张力障碍2例。颞部耳前骨窗超声能够观察到植入电极的高强回声点状信号,可以观察到中脑周围与电极植入相关解剖结构,以及与植入电极的关系。术后随访4~24个月;9例帕金森病药物“关”状态统一帕金森病评定量表评分改善率为60.0%;药物“开”状态改善率为44.0%;2例肌张力障碍病人肌张力障碍运动评分量表评分改善率为40%、80%;随访期间,2例发生构音障碍,经程控后改善;1例出现癫痫发作;无出血等并发症。结论 经颅超声能够显示黑质以及植入电极的高回声信号,是确定脑深部刺激电极或黑质内外正确位置的一种操作方便的辅助技术。     

脑深部电刺激治疗帕金森病作用机制的探讨

目的从蛋白组学的角度探索脑深部电刺激(DBS)与毁损术治疗帕金森病的机制是否类同。方法采用荧光差异凝胶电泳(DIGE)技术,测定3例行双侧丘脑底核DBS治疗的帕金森病病人脑脊液中蛋白,在手术前(未干预组)、手术7 d后但未刺激前(微毁损组)和刺激1周后(DBS组)的表达变化。另留取3例非中枢系统疾病病人的脑脊液蛋白作为正常对照组。结果未干预组和微毁损组、未干预组和DBS组、微毁损组和DBS组的组间比较分别发现14、18和13个明显差异蛋白点。除3个蛋白点外,未干预组和微毁损组与未干预组和DBS组的组间蛋白差异点完全不同;且在这3个相同的蛋白点中,两个蛋白点呈相反方向表达。结论结果初步提示DBS与毁损术治疗帕金森病的机制不相同。     

Bowstringing como complicación de estimulación cerebral profunda

Deep brain stimulation (DBS) is an established surgical therapy for intractable movement disorders, such as Parkinson's disease, essential tremor and dystonia. As the number of treated patients has increased rapidly, new sets of problems about complications of DBS have arisen. Bowstringing is defined as abnormal tethering of leads between the pulse generators and stimulating electrode, associated with pain and contracture of the neck over the extension cable.We report the case of a 56-year-old woman with a history of advanced Parkinson's disease who had been treated by implantation of a bilateral, subthalamic nucleus, deep brain stimulator. A car accident caused the rupture of the right electrode, which was replaced. Six months after the replacement the patient presented disabling pain and tension in the neck where deep brain extension cables were located. A cervical incision was performed to excise scar tissue.Bowstringing is a rare complication of DBS and although patients sometimes report discomfort and tension in the cervical region, surgical procedures are not normally required.     

Twiddler’s syndrome in a patient with a deep brain stimulation device for generalized dystonia

Deep brain stimulation (DBS) is the technique of neurostimulation of deep brain structures for the treatment of conditions such as essential tremor, dystonia, Parkinson’s disease and chronic pain syndromes. The procedure uses implanted deep brain stimulation electrodes connected to extension leads and an implantable pulse generator (IPG). Hardware failure related to the DBS procedure is not infrequent, and includes electrode migration and disconnection. We describe a patient who received bilateral globus pallidus internus DBS for dystonia with initially good clinical response, but the device eventually failed. Radiographs showed multiple twisting of the extension leads with disconnection from the brain electrodes and a diagnosis of Twiddler’s syndrome was made. Twiddler’s syndrome was first described in patients with cardiac pacemakers. Patients with mental disability, elderly and obese patients are at increased risk. Twiddler’s syndrome should be suspected whenever there is a failure of the DBS device to relieve symptoms previously responsive to stimulation. Surgical correction is usually required.     

Somatosensory evoked potentials (SEPs) recorded from deep brain stimulation (DBS) electrodes in the thalamus and subthalamic nucleus (STN).

OBJECTIVE: To examine the location of deep brain stimulation (DBS) electrode somatosensory evoked potentials (SEPs) and determine the generators of the median nerve SEPs recorded in thalamus and subthalamic nucleus (STN). METHODS: SEPs were recorded from contacts of DBS electrodes and microelectrodes in thalamus and STN to establish the latencies of N13, N18 and N20 in 24 patients (8 tremor, 4 chronic pain, 12 Parkinson disease) undergoing chronic DBS. RESULTS: A large SEP with a mean latency of 17.9+/-1.7 ms was recorded from thalamic contacts. Phase reversal occurred at the horizontal level of the anterior commissure-posterior commissure line. Smaller potentials with similar latency but no reversal could be recorded from STN electrodes. CONCLUSIONS: We propose that the thalamic SEP is generated by excitatory post-synaptic potentials in sensory relay neurons in nucleus ventrocaudalis. A small potential in STN at a similar latency, may be due to volume conduction from thalamus. Intraoperative and postoperative SEP recordings from DBS electrodes could be used to determine the optimal position of the contacts relative to the sensory pathways and the choice of contacts for chronic stimulation.     

Stereotactic microdialysis of the basal ganglia in Parkinson's disease

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is an efficacious treatment in patients with advanced Parkinson's disease, yet the mechanisms of STN DBS are poorly understood. The aims of this study were to develop a useful method for studying neurotransmitter alterations during DBS and for the pharmacokinetics of L-dopa in brain tissue. Ten patients with Parkinson's disease participated, whereof two had no previous L-dopa medication. The electrodes and catheters were placed using MRI-guided stereotaxic targeting. Two microdialysis probes were placed, one in the right internal globus pallidus, and one in a brachial vein. The quadripolar deep brain electrodes were placed in the right STN. Microdialysates from brain tissue and blood were collected in 15-min fractions at baseline and during DBS. After stimulation new baseline fractions were taken and finally three fractions during continuous intravenous infusion of L-dopa. Clinical evaluation showed that both DBS and L-dopa infusion gave good relief of rigidity and tremor in all ten patients. During DBS the L-dopa levels in the brain increased in some of the patients but did not persist during the whole stimulation period. The concentration in brain increased substantially during intravenous L-dopa infusion. A number of catecholamines and their metabolites were analysed with high pressure liquid chromatography (HPLC). With our study we could show that this model is suitable for the monitoring of neurotransmitters and for pharmacokinetic studies in human brain, although we found that the sampling time was too short to follow the possible alterations in brain activity caused by DBS.     

MRI- and skull x-ray-based approaches to evaluate the position of deep brain stimulation electrode contacts--a technical note

Deep brain stimulation (DBS) has developed into an established therapy for the treatment of movement disorders, most commonly Parkinson's disease and tremor of different etiology. The subthalamic nucleus (STN) has evolved as the preferred target for DBS in patients with idiopathic Parkinson's disease. The principal target for DBS in tremor patients is the ventrolateral thalamus which has been explored for ablative procedures (thalamotomy) for some decades. Detailed information about the exact site of chronic stimulation, i.e. the location of the active electrode contacts, are important to map the actual subcortical structures modulating the therapeutic effects of DBS. We compared two different methods not requiring intra-operative teleradiography to determine the stereotactic coordinates of single electrode contacts, (i) correlation of pre- and post-operative MRI, and (ii) post-operative stereotactic skull x-ray. For seven patients implanted bilateral with quadripolar DBS electrodes the coordinates for each contact were determined by both approaches. This revealed for a total of 56 electrode contacts a median euclidean 3D-difference between both methods of 1.18 mm (range 0.42 to 1.93 mm). These data suggest that both approaches may be used to determine the position of single electrode contacts.     

Accuracy of stereotactic electrode placement in deep brain stimulation by intraoperative computed tomography

The purpose of this study was to evaluate the accuracy of stereotactic electrode placement in patients undergoing deep brain stimulation by using pre- and postoperative computed tomography (CT). Twenty-three patients with movement disorders (Parkinson's disease (n = 7), tremor (n = 9), dystonia (n = 7)) treated with bilateral deep brain stimulation (DBS) (overall 46 target points) were investigated. The target point of the electrode was planned stereotactically in combination with a preoperative stereotactic helical computed tomography (CT). A postoperative CT, which was carried out still in the operating room while the patient had the stereotactic frame on the head, was performed in order to control the position of the electrodes in relation to the previously planned target point. The position of the four electrode contacts was measured according to the Talairach space (AC–PC line) and compared with the coordinates of the planned target point. The mean spatial distance of planned target perpendicular to the electrode was 1.32 ± 0.75 mm. These results show the high accuracy of stereotactic implantation of DBS electrodes assisted by pre- and postoperative image fusion with computed tomography (CT).     

OFF-off rebound dyskinesia in subthalamic nucleus deep brain stimulation of Parkinson's disease.

A 61-year-old man with Parkinson's disease (PD), motor fluctuations, and dyskinesias underwent bilateral implantation of deep brain stimulation (DBS) electrodes in the subthalamic nucleus (STN). One month after surgery, DBS was optimized to bilateral monopolar settings at the most proximal electrode just superior to the STN, which improved motor fluctuations and dyskinesias. At several postoperative evaluations off medications overnight, both stimulators were turned off and within 60 seconds he developed severe dyskinesias. When the stimulators were turned back on, the dyskinesias soon resolved. This article is a first report of a unique pattern of rebound-type dyskinesia that occurred in the off medication state produced by stopping STN DBS.     

Human central nervous system circuits examined through the electrodes implanted for deep brain stimulation.

High-frequency repetitive electrical stimulation of deep brain structures through stereotactically implanted electrodes is a well established procedure for symptomatic treatment of patients with Parkinson's disease and other neurological conditions involving dysfunction of basal ganglia circuits. Target nuclei have mainly three structures: the nucleus ventrointermedius externus of the thalamus (Vim), the globus pallidus internum (GPi) and the subthalamic nucleus (STN). Having an electrode implanted in deep brain tissue offers a unique opportunity for carrying out neurophysiological studies on the neural structures and pathways that are within the area of influence of the electrode. This possibility has been used by many researchers in the field that either recorded the activity from, or applied stimulation to, the electrode implanted in the target nuclei. The results of these studies have brought improvement on our knowledge of human brain circuitry and provided cues for understanding better the effects of deep brain stimulation (DBS). We present here a review of the literature on the use of DBS electrodes for externally controlled recording or stimulation. The results reported show some of the possibilities of this new dimension of neurophysiological studies and are, most likely, a preliminary account of future major interventions on human brain.     

Role of electrode design on the volume of tissue activated during deep brain stimulation

Deep brain stimulation (DBS) is an established clinical treatment for a range of neurological disorders. Depending on the disease state of the patient, different anatomical structures such as the ventral intermediate nucleus of the thalamus (VIM), the subthalamic nucleus or the globus pallidus are targeted for stimulation. However, the same electrode design is currently used in nearly all DBS applications, even though substantial morphological and anatomical differences exist between the various target nuclei. The fundamental goal of this study was to develop a theoretical understanding of the impact of changes in the DBS electrode contact geometry on the volume of tissue activated (VTA) during stimulation. Finite element models of the electrodes and surrounding medium were coupled to cable models of myelinated axons to predict the VTA as a function of stimulation parameter settings and electrode design. Clinical DBS electrodes have cylindrical contacts 1.27 mm in diameter (d) and 1.5 mm in height (h). Our results show that changes in contact height and diameter can substantially modulate the size and shape of the VTA, even when contact surface area is preserved. Electrode designs with a low aspect ratio (d/h) maximize the VTA by providing greater spread of the stimulation parallel to the electrode shaft without sacrificing lateral spread. The results of this study provide the foundation necessary to customize electrode design and VTA shape for specific anatomical targets, and an example is presented for the VIM. A range of opportunities exist to engineer DBS systems to maximize stimulation of the target area while minimizing stimulation of non-target areas. Therefore, it may be possible to improve therapeutic benefit and minimize side effects from DBS with the design of target-specific electrodes.