Transnasal endoscopy-guided percutaneous access to the sphenopalatine ganglion for neurostimulation in the treatment of primary headache: operative technique and feasibility

Abstract Objectives: Cluster headache is considered a trigeminal autonomic cephalalgia and may present with characteristic symptoms of sympathetic/parasympathetic activation on the affected side of the face, such as nasal discharge, tearing, and conjunctival injection. Invasive therapies targeting the sphenopalatine ganglion have been performed in these headache syndromes and can have a medication-sparing effect, especially in refractory, difficult-to-manage cases. The gate control theory of pain suggests that electric pulses delivered to nerve tissues can modulate neuronal activity, thus aiding in management of nociceptive or neuropathic pain, and studies have demonstrated the efficacy and safety of sphenopalatine ganglion neurostimulation. Within this context, we sought to assess the feasibility of a new surgical technique for neurostimulation of the sphenopalatine ganglion in a cadaver dissection model. Methods: The technique was developed through dissection of two cadaver heads. We divided the procedure into two stages: an endonasal endoscopic approach to expose the sphenopalatine ganglion and confirm electrode placement, and a cervicofacial approach to introduce the electrode array and position the internal pulse-generator unit. Computed tomography was performed to confirm implant placement at the end of the procedure. Results: The pulse-generator unit was successfully placed through a retroauricular incision, as is already standard for cochlear implant placement. This should reduce the incidence of perioperative sequelae, especially pain and swelling in the oral region, which are a common complication of previous approaches used for this purpose. Control imaging confirmed proper electrode placement. The device used in this study allows the patient to modulate the intensity of the stimulus, reducing or even obviating the need for drug therapy. Conclusion: The novel technique described herein, based on percutaneous access guided by transmaxillary endoscopy, can provide great precision in electrode array positioning and decreased perioperative morbidity, combining the advantages of endoscopic approaches with those of the retroauricular route. Level of evidence: 3.

Roadmap of Medical Device for Implanted Brain-computer Interface / 中国医疗器械杂志

Implanted brain-computer interface (iBCI) is a system that establishes a direct communication channel between human brain and computer or an external devices by implanted neural electrode. Because of the good functional extensibility, iBCI devices as a platform technology have the potential to bring benefit to people with nervous system disease and progress rapidly from fundamental neuroscience discoveries to translational applications and market access. In this report, the industrialization process of implanted neural regulation medical devices is reviewed, and the translational pathway of iBCI in clinical application is proposed. However, the Food and Drug Administration (FDA) regulations and guidances for iBCI were expounded as a breakthrough medical device. Furthermore, several iBCI products in the process of applying for medical device registration certificate were briefly introduced and compared recently. Due to the complexity of iBCI in clinical application, the translational applications and industrialization of iBCI as a medical device need the closely cooperation between regulatory departments, companies, universities, institutes and hospitals in the future.

Comparison of Intraoperative Ultrasound-guided Versus Technique Modified Subclavian Vein Puncture During Implantation of Totally Implanted Port / 肿瘤防治研究

Objective To compare the success rate and complication rate between real-time ultrasound-guided and technique modified methods of right subclavian vein puncture in tumor patients during implantation of totally implanted port, and to evaluate their effectiveness and safety. Methods We randomly divided 260 tumor patients into ultrasound-guided group and technique modified group, and compared the success rate, pneumothorax, arterial injury, ectopic catheter, local hematoma, puncture times, pinch-off syndrome, etc. Results The success rate of primary puncture in the ultrasound-guided group was better than that in the technique modified group (96.92% vs. 86.15%, P=0.002). The overall complication of the ultrasound-guided group was lower than that of the technique modified group (0 vs. 9.23%, P < 0.001). The incidence of pneumothorax (0 vs. 3.85%, P=0.024) and accidental arterial injury (0 vs. 3.08%, P=0.044) in the ultrasound-guided group were lower than those in the technique modified group. There was no arteriovenous fistula and pinch-off syndrome in any group. Conclusion Compared with the technique modified group, the ultrasound-guided group has more advantages in puncture. Patients with vascular variability can be detected in time.

Advances in zebrafish models of tumor / 中国药理学通报

Zebrafish, with unique characteristics, has been widely involved in the study of the occurrence and development of tumors, the development and screening of anti-tumor drugs, and the determination of the best treatment regimen.In this review, we highlight and raise awareness regarding the classification, characteristics and advantages of zebrafish tumor models, helping to understand and apply zebrafish tumor models reasonably.

Efetividade e Segurança da Remoção de Cabos-Eletrodos Transvenosos de Marca-Passos e Desfibriladores Implantáveis no Cenário da Prática Clínica Real / Effectiveness and Safety of Transvenous Removal of Cardiac Pacing and Implantable Cardioverter-defibrillator Leads in the Real Clinical Scenario

Resumo Fundamento Remoção de cabos-eletrodos de dispositivos cardíacos eletrônicos implantáveis (DCEI) é procedimento pouco frequente e sua realização exige longo treinamento profissional e infraestrutura adequada. Objetivos Avaliar a efetividade e a segurança da remoção de cabos-eletrodos de DCEI e determinar fatores de risco para complicações cirúrgicas e mortalidade em 30 dias. Métodos Estudo prospectivo com dados derivados da prática clínica. De janeiro/2014 a abril/2020, foram incluídos, consecutivamente, 365 pacientes submetidos à remoção de cabos-eletrodos, independentemente da indicação e técnica cirúrgica utilizada. Os desfechos primários foram: taxa de sucesso do procedimento, taxa combinada de complicações maiores e morte intraoperatória. Os desfechos secundários foram: fatores de risco para complicações intraoperatórias maiores e morte em 30 dias. Empregou-se análise univariada e multivariada, com nível de significância de 5%. Resultados A taxa de sucesso do procedimento foi de 96,7%, sendo 90,1% de sucesso completo e 6,6% de sucesso clínico. Complicações maiores intraoperatórias ocorreram em 15 (4,1%) pacientes. Fatores preditores de complicações maiores foram: tempo de implante dos cabos-eletrodos ≥ 7 anos (OR= 3,78, p= 0,046) e mudança de estratégia cirúrgica (OR= 5,30, p= 0,023). Classe funcional III-IV (OR= 6,98, p<0,001), insuficiência renal (OR= 5,75, p=0,001), infecção no DCEI (OR= 13,30, p<0,001), número de procedimentos realizados (OR= 77,32, p<0,001) e complicações maiores intraoperatórias (OR= 38,84, p<0,001) foram fatores preditores para mortalidade em 30 dias. Conclusões Os resultados desse estudo, que é o maior registro prospectivo de remoção de cabos-eletrodos da América Latina, confirmam a segurança e a efetividade desse procedimento no cenário da prática clínica real. (Arq Bras Cardiol. 2020; 115(6):1114-1124)

Abstract Background Transvenous lead extraction (TLE) of cardiac implantable electronic devices (CIED) is an uncommon procedure and requires specialized personnel and adequate facilities. Objectives To evaluate the effectiveness and safety of the removal of CIED leads and to determine risk factors for surgical complications and mortality in 30 days. Methods Prospective study with data derived from clinical practice. From January 2014 to April 2020, we included 365 consecutive patients who underwent TLE, regardless of the indication and surgical technique used. The primary outcomes were: success rate of the procedure, combined rate of major complications and intraoperative death. Secondary outcomes were: risk factors for major intraoperative complications and death within 30 days. Univariate and multivariate analysis were used, with a significance level of 5%. Results Procedure success rate was 96.7%, with 90.1% of complete success and 6.6% of clinical success. Major intraoperative complications occurred in 15 (4.1%) patients. Predictors of major complications were: lead dwelling time ≥ 7 years (OR = 3.78, p = 0.046) and change in surgical strategy (OR = 5.30, p = 0.023). Functional class III-IV (OR = 6.98, p <0.001), renal failure (OR = 5.75, p = 0.001), CIED infection (OR = 13.30, p <0.001), number of procedures performed (OR = 77.32, p <0.001) and major intraoperative complications (OR = 38.84, p <0.001) were predictors of 30-day mortality. Conclusions The results of this study, which is the largest prospective registry of consecutive TLE procedures in Latin America, confirm the safety and effectiveness of this procedure in the context of real clinical practice. (Arq Bras Cardiol. 2020; 115(6):1114-1124)

Research progress on cardiac rehabilitation in patients with implanted cardiac defibrillator / 生物医学工程学杂志

Implantable cardioverter defibrillator (ICD) is the most effective measure to prevent sudden cardiac death. However, ICD patients frequently have problems such as decline of exercise tolerance and quality of life, anxiety and depression after operation, which require cardiac rehabilitation (CR). A considerable amount of studies have proved that CR is an effective secondary prevention measure for patients with cardiovascular disease. Its safety and effectiveness have been supported by evidence-based medicine research, which can prevent the recurrence of cardiovascular events, reduce the readmisson rate, and promote healthy behavior and active lifestyle formation of patients, so as to improve the quality of life of patients. This review mainly summarized the necessity, safety, exercise program and economic benefits of CR in ICD patients.

The relationship between neuroticism and sleep quality of patients withpermanent pacemaker implantation:mediating effect of positive psychological capital / 中国实用护理杂志

Objective To investigate the sleep quality of pacemaker implanted patients,to analyze the relationships among neuroticism,positive psychological capital and sleep quality,and to examine the potential mediating effect of positive psychological capital on the relationship between neuroticism and sleep quality. Methods Using convenience sampling, a total of 178 pacemaker implanted patients were interviewed and analyzed in two tertiary hospitals of Shandong province. They were assessed with Big Five Inventory,The Positive Psycap Questionnaireand Pittsburgh Sleep Quality Indexfor the evaluation of neuroticism,positive psychological capital and sleep quality.The Process macro was used to test the mediating effect. Results The mean score of PSQI in patients with pacemaker implantation was (8.48± 4.50), and 71.3％of them had sleep problems.The scores of neuroticism had positively correlated with the PSQI scores(r=0.31, P<0.01), the scores of positive psychological capital had negatively correlated with the PSQI scores(r=- 0.39, P<0.01).The confidence interval from Bootstrap output indicated positive psychological capital played a mediating role between neuroticism and sleep quality (95％CI:0.06-0.23), mediation effect was 0.14, the percentage of mediation effect in total effect was 43.75％. Conclusions The relation of positive psychological capital to neuroticism and sleep quality among pacemaker implanted patients are intimate.Positive psychological capital could mediate the relationship between neuroticism and sleep quality. It is suggested that nurses can improve the patient′s sleep by enhancing the intervention of positive psychological capital according to the personality characteristics of patients.

Management System of Implantable Medical Device in Accordance with JCI Standard Based on HRP System / 中国医疗器械杂志

JCI standard is the most professional and authoritative certification standard of medical quality and safety system in the world. HRP information system is a systematic hospital resource management platform which integrates the existing hospital information resources and establishes a set of unified, efficient, interconnected and information sharing operation and management of the hospital. In order to meet the requirements of closed-loop management of implantable medical devices in the JCI standard, our hospital has established a set of standards which based on the HRP system platform, including access permission, purchase application, entering and leaving the warehouse, bookkeeping charge, cost accounting and postoperative traceability of implanted medical device management system. HRP system improves the management level of implantable medical devices, and realizes the closed-loop management of the whole process of implantable medical devices.

Safety analysis of implanted peritoneal ports in gastric cancer with peritoneal metastasis / 中国肿瘤临床

Objective: Intraperitoneal chemotherapy is increasingly being used in the treatment of gastric cancer with peritoneal me-tastasis, because the drug can directly act on the metastatic nodules. Repeated treatment can be administered through implanted ports, provided the ports are appropriately managed. Our study aimed to investigate the safety of peritoneal port implantation in pa-tients with gastric cancer with peritoneal metastasis. Methods: We retrospectively reviewed the records of patients undergoing intra-peritoneal port implantation for the administration of chemotherapy between June 2015 and June 2018 to investigate the causes of complications and to discuss their management and prevention. Results: Fifty-five ports were implanted in 54 patients with median us-age time of 8.4 (0.8-32.0) months. Complications occurred at 13 port sites (23.6%), including obstruction (7.3%), severe pain (5.5%), in-fection (3.6%), reflux (3.6%), access difficulty (1.8%), and subcutaneous mass formation (1.8%). The median interval from the time of port implantation to the development of complications was 2.1 months. No factor contributing to the complications was identified (P>0.05). Conclusions: Peritoneal port implantation to systematic chemotherapy in patients with gastric cancer with peritoneal metastasis is safe and feasible if the ports can be carefully managed.

The application of sacral neuromodulation in the treatment of female neurogenic lower urinary tract dysfunction / 中国医师杂志

Trauma,iatrogenic injury,and neurological disorders can lead to neurogenic lower urinary tract dysfunction (NLUTD).However,there are some special causes in women,including radical hysterectomy,mid-urethral suspension,pelvic organ prolapse repair,Fowler syndrome,interstitial cystitis etc.Traditional behavioral therapy,drug treatment and surgeries may work less well in patients with NLUTD and may even lead to progression and deterioration of the diseases.A review of current literatures revealed that there is an increasing evidence on the application of sacral neuromodulation (SNM) in the treatment of NLUTD in female.This review will provide a summary of the known mechanisms of female NLUTD and the effectiveness of SNM.

Application of sacral neuromodulation in lower urinary tract diseases related to pelvic floor dysfunction / 中国医师杂志

Pelvic floor dysfunction associated with lower urinary tract diseases,is a common disease in women.Sacral neuromodulation is a safe and effective new technique with small trauma,which has significant advantages for patients with refractory pelvic floor dysfunction-related lower urinary tract diseases and has good clinical application prospects.

La colocación de los electrodos para el registro electronistagmográfico

Fundamento: la calidad de un registro nistagmográfico durante los estudios del sistema vestibular, depende de la adecuada selección y colocación de los electrodos, los cuáles suelen ser ubicados en puntos específicos de la órbita ocular para permitir la recolección de la variación de potencial eléctrico generado entre la córnea y la retina causada por las sacudidas del nistagmo inducido o natural. Objetivo: presentar los resultados experimentales que demuestran esta influencia al cuantificar el efecto sobre los registros. Desarrollo: se empleó la técnica de estimulación visual con blanco móvil a diferentes frecuencias de movimiento, y los registros se realizaron en las condiciones de iluminación establecidas para electrooculografía, se utilizó un amplificador biomédico (electronistagmógrafo) de dos canales con frecuencia de muestreo de 1 kHz. Los Resultados obtenidos reflejan el cambio de las tensiones en los registros de acuerdo a la zona de colocación de los electrodos, al existir una zona óptima para el adecuado registro electronistagmográfico. Conclusiones: se demostró la afectación por zonas en los registros en el dominio temporal y de la frecuencia, y su influencia en la generación de errores en el diagnóstico topográfico de enfermedades que afectan el Sistema Vestibular.

Background: quality of record of electronystagmography during the studies of the vestibular system depends on the proper selection and placement of the electrodes, which are usually located at specific points in the eye socket to allow the collection of the variation of electric potential generated between the cornea and the retina caused by the jerking of the induced or natural nystagmus. Objective: to present the experimental results that demonstrate this influence by quantifying the effect on the records. Development: it was used the technique of visual stimulation with moving target at different frequencies of movement, and the records were made under the lighting conditions established in the published standard for electrooculography, using a two-channel amplifier with a sampling frequency of 1 kHz. The results obtained reflect the change in the tensions in the records according to the electrode placement zone, there being an optimal zone for the adequate record of electronystagmography. Conclusions: the affectation by zones in the records in the temporal domain and the frequency was demonstrated, and its influence in the generation of errors in the topographic diagnosis of diseases that affect the Vestibular System.

Relationship of Electromechanical Dyssynchrony in Patients Submitted to CRT With LV Lead Implantation Guided by Gated Myocardial Perfusion Spect / Relação entre Dissincronismo Elétrico e Mecânico em Pacientes Submetidos a TRC com Implante do Eletrodo de VE Orientado pela Cintilografia GATED SPECT

Abstract Background: Heart failure (HF) affects more than 5 million individuals in the United States, with more than 1 million hospital admissions per year. Cardiac resynchronization therapy (CRT) can benefit patients with advanced HF and prolonged QRS. A significant percentage of patients, however, does not respond to CRT. Electrical dyssynchrony isolated might not be a good predictor of response, and the last left ventricular (LV) segment to contract can influence the response. Objectives: To assess electromechanical dyssynchrony in CRT with LV lead implantation guided by GATED SPECT. Methods: This study included 15 patients with functional class II-IV HF and clinically optimized, ejection fraction of 35%, sinus rhythm, left bundle-branch block, and QRS ≥ 120 ms. The patients underwent electrocardiography, answered the Minnesota Living with Heart Failure Questionnaire (MLHFQ), and underwent gated myocardial perfusion SPECT up to 4 weeks before CRT, being reassessed 6 months later. The primary analysis aimed at determining the proportion of patients with a reduction in QRS duration and favorable response to CRT, depending on concordance of the LV lead position, using chi-square test. The pre- and post-CRT variables were analyzed by use of Student t test, adopting the significance level of 5%. Results: We implanted 15 CRT devices, and 2 patients died during follow-up. The durations of the QRS (212 ms vs 136 ms) and the PR interval (179 ms vs 126 ms) were significantly reduced (p < 0.001). In 54% of the patients, the lead position was concordant with the maximal delay site. In the responder group, the lateral position was prevalent. The MLHFQ showed a significant improvement in quality of life (p < 0.0002). Conclusion: CRT determines improvement in the quality of life and in electrical synchronism. Electromechanical synchronism relates to response to CRT. Positioning the LV lead in the maximal delay site has limitations.

Resumo Fundamento: A insuficiência cardíaca (IC) afeta mais de 5 milhões de pessoas nos Estados Unidos, com mais de 1 milhão de internações/ano. A terapia de ressincronização (TRC) pode beneficiar pacientes com IC avançada e QRS alargado; entretanto, percentual significativo de pacientes não respondem à TRC. O dissincronismo elétrico isolado pode não representar um bom preditor de resposta, e o local da última ativação do ventrículo esquerdo (VE) pode influenciar na resposta. Objetivos: Avaliar o dissincronismo eletromecânico na TRC com o implante do eletrodo do VE orientado por GATED SPECT. Métodos: Incluídos 15 pacientes com IC classe funcional II-IV, otimizados clinicamente, com fração de ejeção de 35%, ritmo sinusal, bloqueio de ramo esquerdo, QRS ≥ 120 ms. Realizaram eletrocardiograma, Questionário Minnesota Vivendo com Insuficiência Cardíaca (MLHFQ) e cintilografia GATED SPECT até 4 semanas antes do implante. Reavaliados 6 meses após. Análise primária visou determinar a proporção de pacientes com redução da duração do QRS e resposta favorável à TRC dependendo da concordância ou não na posição do eletrodo, utilizando teste Qui-Quadrado. Análise das variáveis pré e pós TRC foi feita através do teste t de Student, assumindo significância de 5%. Resultados: Realizamos 15 implantes com 2 óbitos no seguimento. As reduções das durações do QRS (212 ms vs 136 ms) e do IPR (179 ms vs 126 ms) foram significativas (p < 0,001). Em 54%, o eletrodo foi concordante com o local de maior atraso. No grupo respondedor, a posição lateral foi prevalente. O MLHFQ mostrou melhora significativa da qualidade de vida (p < 0,0002). Conclusão: A TRC determina melhora da qualidade de vida e do sincronismo elétrico. O sincronismo eletromecânico relaciona-se com a resposta à TRC. O posicionamento do eletrodo de VE no sítio de maior retardo tem limitações.

Micro-implanted-anchorage safety: cortical bone thickness in the maxillary posterior region of skeletal class II malocclusion / Seguridad en el micro-implante de anclaje: espesor del hueso cortical en la región posterior del maxilar en maloclusión de clase esquelética tipo II

Cone Beam Computed Tomography (CBCT) measurement of cortical bone thickness and implantation angle in the maxillary posterior region was used to provide reference for the safety of Micro-Implanted-Anchorage (MIA) implantation in skeletal class II malocclusion. Twenty samples of CBCT images were collected from orthodontics patients (ages, 12-40 years) in Shanxi Medical University Stomatological Hospital, the thickness of cortical bone was measured at 45°, 60° and 90° from the alveolar crest, being at 4 mm, 6 mm and 8 mm, respectively. SPSS17.0 statistical software was used to analyze the data, and the one-way ANOVA and LSD method were compared. There was a significant difference in the thickness of the cortical bone obtained by implanting MIA at the same height of different angle (P≤0.05). The greater the inclination angle of the implanted MIA, the thicker the cortical bone. Also, the higher the implant site, the thicker the cortical bone thickness. Finally, the greater the thickness of the cortical bone in the maxillary posterior region of skeletal class II malocclusion, the greater the thickness of the cortical bone. At the same implantation height, implanted MIA with a tilt angle of 45º to 60º, 90º to obtain the best cortical bone thickness.

La medición del grosor del hueso cortical y del ángulo de implantación en la región posterior del maxilar por tomografía computarizada de haz cónico (TCHC) se utilizó para proporcionar una referencia para la implantación y el anclaje seguros de un Micro-Implante de Anclaje (MIA) en la maloclusión de clase esquelética tipo II. Veinte muestras de imágenes de TCHC fueron obtenidas de pacientes de ortodoncia (12-40 años) en el Hospital Estomatológico de la Universidad Médica de Shanxi. Se midió el grosor del hueso cortical a 45°, 60° y 90° de la cresta alveolar, encontrándose a 4 mm, 6 mm y 8 mm, respectivamente. Se utilizó el software estadístico SPSS 17.0 para analizar los datos, y se compararon con los métodos ANOVA y LSD de un factor. Hubo una diferencia significativa en el grosor del hueso cortical obtenido al implantar el MIA a la misma altura en diferentes ángulos (P <0,05). Cuanto mayor es el ángulo de inclinación del MIA implantado, más grueso es el hueso cortical. También, cuanto más alto es el sitio del implante, más grueso es el grosor del hueso cortical. Finalmente, cuanto mayor sea el grosor del hueso cortical en la región posterior del maxilar, en la maloclusión de clase esquelética tipo II, mayor será el grosor del hueso cortical.

Técnica de Alemán y Pico para la profundización del surco vestibular inferior / Alemán and Pico technique for deepening the inferior vestibular edge

A pesar de los avances en la tecnología para preservar la dentición, aún se requiere la rehabilitación del sistema masticatorio en pacientes desdentados parcial o totalmente, lo que resulta difícil y frustrante -- tanto para los afectados como para los protesistas -- si existe atrofia grave del hueso alveolar. Este problema se puede solucionar mediante una intervención quirúrgica denominada profundización del vestíbulo, dirigida a lograr el aumento de la cresta alveolar y, con ello, el soporte de las prótesis dentales. A tal efecto, en el presente trabajo se propone y describe una nueva opción terapéutica: la técnica de Alemán y Pico, para la profundización del surco vestibular inferior, la cual no es tan invasiva y resulta factible cuando no se cuenta con las condiciones necesarias para colocar implantes, ya sea por escasez de recursos materiales o por situaciones propias del paciente

In spite of the advances in technology to preserve the eruption of teeth, the rehabilitation of the masticatory system is still required in partial or totally toothless patients, what is difficult and frustrating -- either for those affected patients or for the prosthesists -- if serious atrophy of the alveolar bone exists. This problem can be solved by means of a surgical procedure denominated deepening of the vestibule directed to achieve the increase of the alveolar crest and, with it, the support of the dental prosthesis. To such an effect, this work intends and describes a new therapeutic option: the Alemán and Pico technique, for deepening of the inferior vestibular edge, which is not so invasive and it is feasible when the necessary conditions to place an implant are not available, either due to shortage of material resources or due to situations of the patients themselves

A lost cable: «reel¼ syndrome / Un cable suelto: síndrome del «carrete¼

Abstract: Lead dislodgement syndromes (twiddler, ratchet or reel syndromes) are rare causes of cardiac stimulation device malfunction that can occur most commonly early after device implantation. In most cases, lead replacement (due to extensive damage) or reposition (due to displacement) is needed. We present a case of reel syndrome involving the left ventricular lead of a (AU)

Resumen: Los síndromes de desprendimiento de los cables (síndrome de "tweedler", trinquete o carrete) son causas raras de disfunción del dispositivo de estimulación cardiaca, que generalmente ocurren en el periodo temprano después del implante. En la mayoría de los casos, se requiere el reemplazo del cable (debido a daños extensos) o el reposicionamiento (debido al desplazamiento). Presentamos un caso de síndrome del carrete que involucra de manera exclusiva el cable ventricular izquierdo de un dispositivo de resincronización-desfibrilador cardiaco.(AU)

Characterization of Tetrodes Coated with Au Nanoparticles (AuNPs) and PEDOT and Their Application to Thalamic Neural Signal Detection in vivo

Tetrodes, consisting of four twisted micro-wires can simultaneously record the number of neurons in the brain. To improve the quality of neuronal activity detection, the tetrode tips should be modified to increase the surface area and lower the impedance properties. In this study, tetrode tips were modified by the electrodeposition of Au nanoparticles (AuNPs) and dextran (Dex) doped poly (3,4-ethylenedioxythiophene) (PEDOT). The electrochemical properties were measured using electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). A decrease in the impedance value from 4.3 MΩ to 13 kΩ at 1 kHz was achieved by the modified tetrodes. The cathodic charge storage capacity (CSC(C)) of AuNPs-PEDOT deposited tetrodes was 4.5 mC/cm², as determined by CV measurements. The tetrodes that were electroplated with AuNPs and PEDOT exhibited an increased surface area, which reduced the tetrode impedance. In vivo recording in the ventral posterior medial (VPM) nucleus of the thalamus was performed to investigate the single-unit activity in normal rats. To evaluate the recording performance of modified tetrodes, spontaneous spike signals were recorded. The values of the L-ratio, isolation distance and signal-to-noise (SNR) confirmed that electroplating the tetrode surface with AuNPs and PEDOT improved the recording performance, and these parameters could be used to effectively quantify the spikes of each cluster.

Clinical application of right outflow tract septal pacing of active electrode lead / 中国医师进修杂志

Objective To investigate the advantage and disadvantage of the right ventricular outflow septal pacing.Methods Eighty patients requiring pacemaker because of slow arrhythmia were randomly divided into the active fixation group and passive fixation group.The implantation time, radiation exposure time and changes of electrocardiogram were compared between 2 groups,and the heart function changes 1 year after treatment were observed by color Doppler ultrasound.Results The implantation time and radiation exposure time in active fixation group were significantly longer than those in passive fixation group: (20.00 ± 3.48) min vs.(15.00 ± 2.67) min and (9.45 ± 3.48) min vs.(6.78 ± 2.67)min,and there were statistical differences(P<0.05).The QRS duration and QTc duration in active fixation group were significantly shorter than those in passive fixation group:(0.119 2 ± 0.042 1)s vs.(0.142 3 ± 0.032 4)s and(0.403 5 ± 0.026 8)s vs.(0.442 7 ± 0.054 1)s,and there were statistical differences(P<0.05).In active fixation group,there were no statistical differences in left atrial diameter, left ventricular end-diastolic diameter, left ventricular minor axis decurtaion rate and left ventricular ejection fraction, compared before treatment and 1 year after treatment (P>0.05).Conclusions The application of the active electrode lead in the right outflow trace septal pacing is more associated with wider physiological ventricular function.

Comparison between left ventricular quadripolar leads and traditional left ventricular bipolar leads / 心血管康复医学杂志

While receiving cardiac resynchronization therapy (CRT) ,traditional left ventricular lead implantation may fail due to anatomical abnormality of heart vein ,poor left ventricular pacing threshold ,lead dislocation and ra-dial nerve stimulation etc .So left ventricular quadripolar leads rise in response to the proper time and condition .The present article made a brief review on research progress of application of left ventricular quadripolar leads in clinic .