Changqing Jiang

Carbon Nanotube Yarns for Deep Brain Stimulation Electrode

A new form of deep brain stimulation (DBS) electrode was proposed that was made of carbon nanotube yarns (CNTYs). Electrode interface properties were examined using cyclic voltammetry (CV) and electrochemical impedance spectrum (EIS). The CNTY electrode interface exhibited large charge storage capacity (CSC) of 12.3 mC/cm2 which increased to 98.6 mC/cm2 after acid treatment, compared with 5.0 mC/cm2 of Pt-Ir. Impedance spectrum of both untreated and treated CNTY electrodes showed that finite diffusion process occurred at the interface due to their porous structure and charge was delivered through capacitive mechanism. To evaluate stability electrical stimulus was exerted for up to 72 h and CV and EIS results of CNTY electrodes revealed little alteration. Therefore CNTY could make a good electrode material for DBS.

Artifact properties of carbon nanotube yarn electrode in magnetic resonance imaging

OBJECTIVE Deep brain stimulating (DBS) is a rapidly developing therapy that can treat many refractory neurological diseases. However, the traditional DBS electrodes which are made of Pt-Ir alloy may induce severe field distortions in magnetic resonance imaging (MRI) which leads to artifacts that will lower the local image quality and cause inconvenience or interference. A novel DBS electrode made from carbon nanotube yarns (CNTYs) is brought up to reduce the artifacts. This study is therefore to evaluate the artifact properties of the novel electrode. APPROACH We compared its MR artifact characteristics with the Pt-Ir electrode in water phantom, including its artifact behaviors at different orientations as well as at various off-center positions, using both spin echo (SE) and gradient echo (GE) sequences, and confirmed its performance in vivo. MAIN RESULTS The results in phantom showed that the CNTY electrode artifacts reduced as much as 62% and 74% on GE and SE images, respectively, compared to the Pt-Ir one. And consistent behaviors were confirmed in vivo. The susceptibility difference was identified as the dominant cause in producing artifacts. SIGNIFICANCE Employing the CNTY electrode may generate much less field distortion in the vicinity, improve local MR image quality and possibly be beneficial in various aspects.

Automated Segmentation and Reconstruction of the Subthalamic Nucleus in Parkinson's Disease Patients

In the treatment of Parkinsons disease for deep brain stimulation (DBS), the subthalamic nucleus (STN) is the most important target on a specific brain nucleus. Although procedural details are well established, targeting STN remains problematic because of its variable location and relatively small size.

An Experimental Study of Deep Brain Stimulation Lead Fracture: Possible Fatigue Mechanisms and Prevention Approach

Lead fracture is a common and troublesome hardware‐related complication in deep brain stimulation therapy. Frequent cervical movements are suspected as the main cause, but the underlying mechanisms are still unclear. We propose the integrity of the helical structure of the lead wires is important and conduct systematic experiments to demonstrate this. We aim to provide a new view on how lead fracture takes place.

Reliability evaluation and improvement of deep brain stimulator based on accelerated flexing test

Reliability of a deep brain stimulator is very important. In this paper, the reliability performance of the extension and lead of a deep brain stimulator was evaluated based on an accelerated flexing test, and through a weakness detection, segment level improvement and assembly level improvement procedure, failure frequency was reduced and bending count till failure values got significant increased for the weak points of the extension and lead. The deep brain stimulator is now under clinical trial, and the results showed that the method and improvement strategy is helpful to reliability design and process improvement.