To observe the effect of percutaneous electrical stimulation on peripheral nerve regeneration, a model was created on the sciatic nerves of 56 rats from either sectioned and followed by direct anastomosis or clamping of the nerve. The indices, such as conducting velocity of nerve, maximal induced action potential of muscle, growth speed of nerve, rateof axon crossing anastomosis site, number of muscular fiber on transverse area and weight of muscle by autocontrol were compared. In this study, 36 rats were divided into two groups, 24 rats in Group 1 and 12 rats in Group 2. In Gourp 1, both sciatic nerves were sectioned and was anastomozed 4 weeks later. One side of the nerve was stimulated with percutaneous electric current, the other side was served as control. In Group 2, both sides of nerves were clamped and the electical stimulationwas carried out on one side. The parameters of the electric current were 2～5HZ, 0.4m/s, 24～48V. The electrophysiological and histomorphological features were observed 1 to 6 weeks after operation. The results showed that in the stimulatedside, the indices were all superior to that of the control side. This suggestedthat electrical stimulation could promote peripheral nerve regeneration.
Spinal cord stimulation (SCS) for pain is usually implanted as an open loop system using unchanged parameters. To avoid the under and over stimulation caused by lead migration, evoked compound action potentials (ECAP) is used as feedback signal to change the stimulating parameters. This study established a simulation model of ECAP recording to investigate the relationship between ECAP component and dorsal column (DC) fiber recruitment. Finite element model of SCS and multi-compartment model of sensory fiber were coupled to calculate the single fiber action potential (SFAP) caused by single fiber in different spinal cord regions. The synthetized ECAP, superimposition of SFAP, could be considered as an index of DC fiber excitation degree, because the position of crests and amplitude of ECAP corresponds to different fiber diameters. When 10% or less DC fibers were excited, the crests corresponded to fibers with large diameters. When 20% or more DC fibers were excited, ECAP showed a slow conduction crest, which corresponded to fibers with small diameters. The amplitude of this slow conduction crest increased as the stimulating intensity increased while the amplitude of the fast conduction crest almost remained unchanged. Therefore, the simulated ECAP signal in this paper could be used to evaluate the degree of excitation of DC fibers. This SCS-ECAP model may provide theoretical basis for future clinical application of close loop SCS base on ECAP.
An experimental study on Holland pigs was designed to evaluate the effect of direct current stimulation on the rate of epidermie regeneration. The 44 animals were divided into four groups, each of eleven animals and the stimulation levels were 10~uADC, 30~uADC, 50~uADC,0~uADC respectively. The results showed that the rate of regeneration of epidermic cell and wound healing was faster with the DC stimulation directly than indirectly, especially in the area of negative electrode and the rate of wound healing with the DC stimulation indirectly was faster than without DC stimulation. Proper applications dircct eurrent of appropriate intensity were definitely beneficial in the treatnent of patienls donor site after removing a thick split-thickness skin graft.
ObjectiveTo explore the best nursing regimen for patients with severe Tardive dyskinesia (TD) after deep brain stimulation (DBS). MethodsTo analyze the clinical nursing data of 7 patients with TD treated by DBS in our department from January 2018 to August 2019, preoperative assessment of the patient's condition, dyskinesia care, psychological care, preoperative preparation, preoperative guidance, etc. General nursing, observation and nursing of complications, psychological nursing, safety management and rehabilitation training of limb function were carried out after operation discharge to discharge guidance, daily life guidance, DBS device-related education and other post-discharge continuous care to help patients improve quality of life. The changes of TD symptoms were assessed with the abnormal involuntary movement scale -LRB-AIMS, the nursing effect was assessed with the psychiatric nursing observation sc-Nosiee (NOSIE) , and the self-care ability was assessed with the ability of daily livin-ADL- scale (ADL). ResultsAll of the 7 TD patients recovered well after operation, without complications caused by improper nursing, and the TD symptoms were relieved. The AIMS and NOSIE scores were significantly lower at 1 month, 3 months and 1 year after operation than those before operation (P<0.05). The ADL scores were significantly higher than those before operation (P<0.05). ConclusionIn order to treat TD patients with DBS operation, we should pay attention to the pertinent nursing in perioperative period and the continuous nursing after discharge, it is of great significance to relieve the symptoms of involuntary movement, improve the mental state and improve the self-care ability of patients with TD.
In order to investigate the effect of deep brain stimulation on diseases such as epilepsy, we developed a closed-loop electrical stimulation system using LabVIEW virtual instrument environment and NI data acquisition card. The system was used to detect electrical signals of epileptic seizures automatically and to generate electrical stimuli. We designed a novel automatic detection algorithm of epileptic seizures by combining three features of field potentials: the amplitude, slope and coastline index. Experimental results of rat epileptic model in the hippocampal region showed that the system was able to detect epileptic seizures with an accuracy rate 91.3% and false rate 8.0%. Furthermore, the on-line high frequency electrical stimuli showed a suppression effect on seizures. In addition, the system was adaptive and flexible with multiple work modes, such as automatic and manual modes. Moreover, the simple time-domain algorithm of seizure detection guaranteed the real-time feature of the system and provided an easy-to-use equipment for the experiment researches of epilepsy control by electrical stimulation.
Objective To review researches of treatment of peripheral nerve injury with neuromuscular electrical stimulation (NMES) regarding mechanism, parameters, and cl inical appl ication at home and abroad. Methods The latest original l iterature concerning treatment of peri pheral nerve injury with NMES was extensively reviewed. Results NMES should be used under individual parameters and proper mode of stimulation at early stage of injury. It could promote nerve regeneration and prevent muscle atrophy. Conclusion NMES plays an important role in cl inical appl ication of treating peripheral nerve injury, and implantable stimulation will be the future.
There are few researches on the modulation effect of transcranial direct current stimulation(tDCS) on complex spatial cognition. Especially, the influence of tDCS on the neural electrophysiological response in spatial cognition is not yet clear. This study selected the classic spatial cognition task paradigm (three-dimensional mental rotation task) as the research object. By comparing the changes in behavior and event-related potentials in different modes of tDCS before, during and after the application of tDCS, this study analyzed the behavioral and neurophysiological effects of tDCS on mental rotation. The comparison between active-tDCS and sham-tDCS showed no statistically significant difference in behavior between different stimulation modes. Still, the changes in the amplitudes of P2 and P3 during the stimulation were statistically significant. Compared with sham-tDCS, the amplitudes of P2 and P3 in active-tDCS mode showed a greater decrease during the stimulation. This study clarifies the influence of tDCS on the event-related potentials of the mental rotation task. It shows that tDCS may improve the brain information processing efficiency during the mental rotation task. Also, this study provides a reference for an in-depth understanding and exploration of the modulation effect of tDCS on complex spatial cognition.
Objective To review the advances of functional electrical stimulation(FES) in treatment of peripheral nerve injuries. Methods By index of recent literature, the measures of stimulation, the mechanisms of FES and unsolved problems were evaluated and analyzed. Results Great advances have been made in the treatment of peripheral nerve injuries. It can not only enhance the regeneration of injured peripheral nerve, but also prevent muscular atrophy. Conclusion FES is an effective treatment for peripheral nerve injuries.
As an emerging non-invasive brain stimulation technique, transcranial direct current stimulation (tDCS) has received increasing attention in the field of stroke disease rehabilitation. However, its efficacy needs to be further studied. The tDCS has three stimulation modes: bipolar-stimulation mode, anode-stimulation mode and cathode-stimulation mode. Nineteen stroke patients were included in this research (10 with left-hemisphere lesion and 9 with right). Resting electroencephalogram (EEG) signals were collected from subjects before and after bipolar-stimulation, anodal-stimulation, cathodal-stimulation, and pseudo-stimulation, with pseudo-stimulation serving as the control group. The changes of multi-scale intrinsic fuzzy entropy (MIFE) of EEG signals before and after stimulation were compared. The results revealed that MIFE was significantly greater in the frontal and central regions after bipolar-stimulation (P < 0.05), in the left central region after anodal-stimulation (P < 0.05), and in the frontal and right central regions after cathodal-stimulation (P < 0.05) in patients with left-hemisphere lesions. MIFE was significantly greater in the frontal, central and parieto-occipital joint regions after bipolar-stimulation (P < 0.05), in the left frontal and right central regions after anodal- stimulation (P < 0.05), and in the central and right occipital regions after cathodal-stimulation (P < 0.05) in patients with right-hemisphere lesions. However, the difference before and after pseudo-stimulation was not statistically significant (P > 0.05). The results of this paper showed that the bipolar stimulation pattern affected the largest range of brain areas, and it might provide a reference for the clinical study of rehabilitation after stroke.
We studied the influence of electrode array parameters on temperature distribution to the retina during the use of retinal prosthesis in order to avoid thermal damage to retina caused by long-term electrical stimulation. Based on real epiretinal prosthesis, a three-dimensional model of electrical stimulation for retina with 4×4 microelectrode array had been established using the finite element software (COMSOL Multiphysics). The steady-state temperature field of electrical stimulation of the retina was calculated, and the effects of the electrode parameters such as the distance between the electrode contacts, the materials and area of the electrode contact on temperature field were considered. The maximum increase in the retina steady temperature was about 0.004℃ with practical stimulation current. When the distance between the electrode contacts was changed from 130 μm to 520 μm, the temperature was reduced by about 0.006℃. When the contact radius was doubled from 130 μm to 260 μm, the temperature decrease was about 0.005℃. It was shown that there were little temperature changes in the retina with a 4×4 epiretinal microelectrode array, reflecting the safety of electrical stimulation. It was also shown that the maximum temperature in the retina decreased with increasing the distance between the electrode contacts, as well as increasing the area of electrode contact. However, the change of the maximum temperature was very small when the distance became larger than the diameter of electrode contact. There was no significant difference in the effects of temperature increase among the different electrode materials. Rational selection of the distance between the electrode contacts and their area in electrode design can reduce the temperature rise induced by electrical stimulation.