Glioblastoma(GBM)is a highly infiltrative brain tumor.The treatment of GBM is challenging due to the existence of blood brain barrier,its highly invasive nature,and its heterogeneity.Given the limitations of conventio...Glioblastoma(GBM)is a highly infiltrative brain tumor.The treatment of GBM is challenging due to the existence of blood brain barrier,its highly invasive nature,and its heterogeneity.Given the limitations of conventional therapies,this Perspective explores the development trajectory of implantable devices,highlighting the advantages of current models.With the progression in research,these implantable devices certainly hold promising potential for GBM therapy.展开更多
A common model of power supply for implantable devices was established to study factors affecting volume conduction energy transfer. Electromagnetic and equivalent circuit models were constructed to study the effect o...A common model of power supply for implantable devices was established to study factors affecting volume conduction energy transfer. Electromagnetic and equivalent circuit models were constructed to study the effect of separation between the source electrode pairs on volume conduction energy transfer. In addition, the parameters of external signal including waveform, amplitude and frequency were analyzed. As the current amplitude did not lead to tissue injury and the current frequency did not cause nerve excitability, the recommended separation be- tween the source electrodes was 3 cm, the proposed waveform of signal source was sinusoidal wave and the opti- mal frequency was 200 KHz. In agar experiment and swine skin experiment, the current transfer efficiencies were 28.13% and 20.65%, respectively, and the energy transfer efficiencies were 9.86% and 6.90%, respectively. In conclusion, we can achieve optimal efficiency of energy transfer by appropriately setting the separation between the source electrode parameters of the signal source.展开更多
Background:Cardiac implantable electronic devices(CIEDs)are essential for preventing sudden cardiac death in patients with cardiovascular diseases,but implantation procedures carry risks of complications such as infec...Background:Cardiac implantable electronic devices(CIEDs)are essential for preventing sudden cardiac death in patients with cardiovascular diseases,but implantation procedures carry risks of complications such as infection,hematoma,and bleeding,with incidence rates of 3–4%.Previous studies have examined individual risk factors separately,but integrated predictive models are lacking.We compared the predictive performance and interpretability of artificial neural network(ANN)and logistic regression models to evaluate their respective strengths in clinical risk assessment.Methods:This retrospective study analyzed data from 180 patients who underwent cardiac implantable electronic device(CIED)implantation in Taiwan between 2017 and 2018.To address class imbalance and enhance model training,the dataset was augmented to 540 records using the Synthetic Minority Oversampling Technique(SMOTE).A total of 13 clinical risk factors were evaluated(e.g.,age,body mass index(BMI),platelet count,left ventricular ejection fraction(LVEF),prothrombin time/international normalized ratio(PT/INR),hemoglobin(Hb),comorbidities,and antithrombotic use).Results:The most influential risk factors identified by the ANN model were platelet count,PT/INR,LVEF,Hb,and age.In the logistic regression analysis,reduced LVEF,lower hemoglobin levels,prolonged PT/INR,and lower BMI were significantly associated with an increased risk of complications.ANN model achieved a higher area under the curve(AUC=0.952)compared to the logistic regression model(AUC=0.802),indicating superior predictive performance.Additionally,the overall model quality was also higher for the ANN model(0.93)than for logistic regression(0.76).Conclusions:This study demonstrates that ANN models can effectively predict complications associated CIED procedures and identify critical preoperative risk factors.These findings support the use of ANN-based models for individualized risk stratification,enhancing procedural safety,improving patient outcomes,and potentially reducing healthcare costs associated with postoperative complications.展开更多
To overcome some of the problems inherent in conventional heating aids such as low gain at high fi'equencies due to acoustic feedback,discomfort in occlusion of the extemal ear canal and so on,implantable middle e...To overcome some of the problems inherent in conventional heating aids such as low gain at high fi'equencies due to acoustic feedback,discomfort in occlusion of the extemal ear canal and so on,implantable middle ear hearing devices(IMEHDs)have been developed over the past two decades.For such kinds of IMEHDs,this paper presents the design of a floating mass piezoelectric actuator using a PMN-30%PT stack as a new type of vibrator.The proposed piezoelectric actuator consists of only three components of a piezoelectric stack,a metal case and a clamp.For the purpose of aiding the design of this actuator,a coupling biomechanics model of human middle ear and the piezoelectric actuator was constructed.This model was built based on a complete set of computerized tomography section images of a healthy volunteer's left ear by reverse engineering technology.The validity of this model was confirmed by comparing the motion of the tympanic membrane and stapes footplate obtained by this model with published experimental measurements on human temporal bones.It is shown that the designed actuator can be implanted on the incus long process by a simple surgical operation,and the stapes footplate displacement by its excitation at 10.5 V root-mean-square(RMS)voltage was equivalent to that from acoustic stimulation at 100 dB sound pressure level(SPL),which is adequate stimulation to the ossicular chain.The corresponding power consumption is 0.04 mW per volt of excitation at 1 kHz,which is low enough for the transducer to be used in an implantable middle ear device.展开更多
With the widespread adoption of ultrasound guidance,Seldinger puncture techniques,and intracardiac electrical positioning technology for the placement of peripherally inserted central catheters in recent years,an incr...With the widespread adoption of ultrasound guidance,Seldinger puncture techniques,and intracardiac electrical positioning technology for the placement of peripherally inserted central catheters in recent years,an increasing number of medical staff and patients now accept peripheral placement of totally implantable venous access devices(TIVADs)in the upper arm.This approach has the advantage of completely avoiding the risks of hemothorax,pneumothorax,and neck and chest scarring.Medical specialties presently engaged in this study in China include internal medicine,surgery,anesthesiology,and interventional departments.However,command over implantation techniques,treatment of complications,and proper use and maintenance of TIVAD remain uneven among different medical units.Moreover,currently,there are no established quality control standards for implantation techniques or specifications for handling complications.Thus,this expert consensus is proposed to improve the success rate of TIVAD implantation via the upper-arm approach,reduce complication rates,and ensure patient safety.This consensus elaborates on the technical indications and contraindications,procedures and technical points,treatment of complications,and the use and maintenance of upper-arm TIVAD,thus providing a practical reference for medical staff.展开更多
Background Cardiac implantable electronic devices （CIEDs） greatly improve survival and life quality of patients. However, there are gender differences regarding both the utilization and benefit of these devices. In ...Background Cardiac implantable electronic devices （CIEDs） greatly improve survival and life quality of patients. However, there are gender differences regarding both the utilization and benefit of these devices. In this prospective CIED registry, we aim to appraise the gender differences in CIED utilization in China. Methods Twenty centers from 14 provinces in China were included in our registry study. All patients who underwent a CIED implantation in these twenty centers between Jan 2015 and Dec 2016 were included. Results A total of 8570 patients were enrolled in the baseline cohort, including 7203 pacemaker, 664 implantable cardiac defibrillators （ICD） implants and 703 cardiac resynchronization therapy device （CRT/D）. Totally, 4117 （48.0%） CIED patients were female, and more than 59% pacemaker patients were female, but women account only one third of ICD or CRT/D implantation in this registry. There were significant differences between genders at pacemaker and ICD indications. Female was more likely received a pacemaker due to sick sinus syndrome （SSS） （63.9% vs. 51.0%, P 〈 0.001）. Female patients receiving an ICD were more likely due to cardiac ion channel disease （29.2% vs. 4.2%, P 〈 0.001）. The percentage of utilization of dual-chamber pacemaker in female patients was significantly higher than male （85.3% vs. 81.1%, P 〈 0.001）. But male patients were more likely received a cardiac resynchronization therapy devices with defibrillator than female （56.5% vs. 41.9%, P = 0.001）. In pacemaker patient, male was more likely to have structure heart disease （31.3% vs. 28.0%, P = 0.002）. In ICD patient, male patients were more likely to have ischemic heart disease （48.2% vs. 29.2%, P 〈 0.001）. The mean age of women at the time of CRT/D implantation was older than men （P = 0.014）. Nonischemic cardiomyopathy （70.9%） was the most common etiology in the patients who underwent the treat？ment of CRT/D, no matter male or female. Conclusions In real-world setting, female do have different epidemiology, pathophysiology and clinical presentation of many cardiac rhythm disorders when compared with male, and all these factors may affect the utilization of CIED implantation. But it also possibility that cultural and socioeconomic features may play a role in this apparent discrimination.展开更多
As cardiac implantable electronic devices(CIED)become more prevalent,it is important to acknowledge potential electromagnetic interference(EMI)from other sources,such as internal and external electronic devices and pr...As cardiac implantable electronic devices(CIED)become more prevalent,it is important to acknowledge potential electromagnetic interference(EMI)from other sources,such as internal and external electronic devices and procedures and its effect on these devices.EMI from other sources can potentially inhibit pacing and trigger shocks in permanent pacemakers(PPM)and implantable cardioverter defibrillators(ICD),respectively.This review analyzes potential EMI amongst CIED and left ventricular assist device,deep brain stimulators,spinal cord stimulators,transcutaneous electrical nerve stimulators,and throughout an array of procedures,such as endoscopy,bronchoscopy,and procedures involving electrocautery.Although there is evidence to support EMI from internal and external devices and during procedures,there is a lack of large multicenter studies,and,as a result,current management guidelines are based primarily on expert opinion and anecdotal experience.We aim to provide a general overview of PPM/ICD function,review documented EMI effect on these devices,and acknowledge current management of CIED interference.展开更多
BACKGROUND Cardiovascular implantable electronic devices(CIEDs)are implanted in an increasing number of patients each year,which has led to an increase in the risk of CIED infection.Antibacterial CIED envelopes locall...BACKGROUND Cardiovascular implantable electronic devices(CIEDs)are implanted in an increasing number of patients each year,which has led to an increase in the risk of CIED infection.Antibacterial CIED envelopes locally deliver antibiotics to the implant site over a short-term period and have been shown to reduce the risk of implant site infection.These envelopes are derived from either biologic or nonbiologic materials.There is a paucity of data examining patient risk profiles and outcomes from using these envelope materials in the clinical setting and comparing these results to patients receiving no envelope with their CIED implantation.AIM To evaluate risk profiles and outcomes of patients who underwent CIED procedures with an antibacterial envelope or no envelope.METHODS After obtaining Internal Review Board approval,the records of consecutive patients who underwent a CIED implantation procedure by a single physician between March 2017 and December 2019 were retrospectively collected from our hospital.A total of 248 patients within this period were identified and reviewed through 12 mo of follow up.The CIED procedures used either no envelope(n=57),a biologic envelope(CanGaroo®,Aziyo Biologics)that was pre-hydrated by the physician with vancomycin and gentamicin(n=89),or a non-biologic envelope(Tyrx^(TM),Medtronic)that was coated with a resorbable polymer containing the drug substances rifampin and minocycline by the manufacturer(n=102).Patient selection for receiving either no envelope or an envelope(and which envelope to use)was determined by the treating physician.Statistical analyses were performed between the 3 groups(CanGaroo,Tyrx,and no envelope),and also between the No Envelope and Any Envelope groups by an independent,experienced biostatistician.RESULTS On average,patients who received any envelope(biologic or non-biologic)were younger(70.7±14.0 vs 74.9±10.6,P=0.017),had a greater number of infection risk factors(81.2%vs 49.1%,P<0.001),received more high-powered devices(37.2%vs 5.8%,P=0.004),and were undergoing more reoperative procedures(47.1%vs 0.0%,P<0.001)than patients who received no envelope.Between the two envelopes,biologic envelopes tended to be used more often in higher risk patients(84.3%vs 78.4%)and reoperative procedures(62.9%vs 33.3%)than non-biologic envelopes.The rate of CIED implant site pocket infection was low(any envelope 0.5%vs no envelope 0.0%)and was statistically equivalent between the two envelope groups.Other reported adverse events(lead dislodgement,lead or pocket revision,device migration or erosion,twiddler’s syndrome,and erythema/fever)were low and statistically equivalent between groups(biologic 2.2%,non-biologic 3.9%,no envelope 1.8%).CONCLUSION CIED infection rates for biologic and non-biologic antibacterial envelopes are similar.Antibacterial envelopes may benefit patients who are higher risk for infection,however additional studies are warranted to confirm this.展开更多
AIM:To compare the surgical outcomes of glaucoma drainage device implantation(GDI)and trans-scleral neodymium:YAG cyclophotocoagulation(CPC)in the management of refractory glaucoma after Descemetstripping automated en...AIM:To compare the surgical outcomes of glaucoma drainage device implantation(GDI)and trans-scleral neodymium:YAG cyclophotocoagulation(CPC)in the management of refractory glaucoma after Descemetstripping automated endothelial keratoplasty(DSAEK).METHODS:This retrospective study on observational case series enrolled 29 patients who underwent DSAEK and posterior anti-glaucoma surgery(15 with GDI and 14 with CPC).The main outcome measures were intraocular pressure(IOP),glaucoma surgery success rate(defined as IOP of 6–21 mm Hg without additional anti-glaucoma operation),number of glaucoma medications,endothelial graft status,and best-corrected visual acuity(BCVA).RESULTS:The mean follow-up time was 34.1 and 21.0mo for DSAEK or glaucoma surgeries,both for the GDI and CPC groups.Both groups showed significant IOP reduction after glaucoma surgery.The GDI group presented a significantly higher success rate in IOP control than the CPC group(60%vs 21.4%,P=0.03).Both procedures significantly decreased the number of glaucoma medications(P=0.03).Forty percent and 57%of cases in the GDI and the CPC group,respectively,experienced endothelial graft failure during follow-up(P=0.36).Significantly worse BCVA after surgery was observed in the CPC group but not in the GDI group.CONCLUSION:Both GDI and CPC significantly decrease IOP in eyes with glaucoma after DSAEK.GDI is preferable to CPC in refractory glaucoma cases after DSAEK,as it manifests a significantly higher success rate for IOP control,similar endothelial graft failure rate,and relatively preserves BCVA than CPC.展开更多
1 Introduction Virtually all cardiovascular diseases including arrhythmias,valve disease,coronary artery disease and heart failure(HF)are increasingly common with advancing age.^([1])Age and disease-related changes in...1 Introduction Virtually all cardiovascular diseases including arrhythmias,valve disease,coronary artery disease and heart failure(HF)are increasingly common with advancing age.^([1])Age and disease-related changes in the heart including fibrosis in the atrial and ventricular myocardium and conduction system,scar tissue from myocardial infarction or other cardiomyopathic processes,increased inflammatory cytokines and changes to ion channels are just some of the factors that predispose older adults to arrhythmias.^([2]).展开更多
Background Remote monitoring(RM)is increasingly employed for all types of cardiac implantable devices(CIED).However,there are only limited data on the acceptance of RM by the elderly.The aim of our study was to ascert...Background Remote monitoring(RM)is increasingly employed for all types of cardiac implantable devices(CIED).However,there are only limited data on the acceptance of RM by the elderly.The aim of our study was to ascertain how octogenarians assess RM technologies compared to younger,presumably technically more literate patients,and what concerns or technical problems the system presents to both groups of patients.Methods The trial was designed as a descriptive,register-based single-center study.The study population consisted of all consecutive patients≥80 years of age(group A,n=94)and all consecutive patients aged≤40 years(group B,n=71),who had undergone implantation of an implantable cardioverter-defibrillator(ICD)between the years of 2009 and 2018 and were using a Home Monitoring?(HM,Biotronik,Berlin,Germany)system.All patients fulfilling entry criteria were approached with a request to participate in the survey.Results A total of 85(90.4%)and 65(91.5%)valid surveys were obtained for groups A and B,respectively.Ninety-two percent of patients in both groups(P=0.903)were satisfied with the limited number of planned ambulatory follow-ups(i.e.,once a year).All patients in both groups(100%)reported that they were satisfied with the HM system,and 97%and 94%of patients in Groups A and B,respectively,ranked it highly beneficial(P=0.68).A significant proportion of patients in both groups were completely unaware of any health-related benefits associated with the use of the HM system(42%in Group A vs.49%in Group B,P=0.4).Among the most frequently reported personal benefits of HM were a sense of safety and security and savings on travel expenses and time.5%and 9%of patients in Groups A and B,respectively,reported that usage of HM caused them some degree of psychological stress(P=0.27).Nearly all patients in both groups reported receiving information on HM from their doctor after ICD implantation.None of Group A reported receiving information from a nurse either before or after ICD implantation,while 14%of Group B patients reported receiving information from a nurse after,but not before ICD implantation.Seven and 51%(P<0.0001)of patients in Group A and B,respectively,sought additional information about HM post-discharge.Conclusions The HM system received good marks and was much appreciated,even in patients over 80 years of age.The level of acceptance and potential psychological stress resulting from RM technology appears to be about the same in older patients as in younger patients.The majority of octogenarians either did not fully understand the clinical benefits of the system or mistakenly thought that the HM system was a substitute for emergency 24-h surveillance.These results highlight the need for better patient education relative to RM technology,with one option being to delegate more of this educational process to specially trained nurses.展开更多
Recently,the inductive coupling link is the most robust method for powering implanted biomedical devices,such as micro-system stimulators,cochlear implants,and retinal implants.This research provides a novel theoretic...Recently,the inductive coupling link is the most robust method for powering implanted biomedical devices,such as micro-system stimulators,cochlear implants,and retinal implants.This research provides a novel theoretical and mathematical analysis to optimize the inductive coupling link efficiency driven by efficient proposed class-E power amplifiers using high and optimum input impedance.The design of the coupling link is based on two pairs of aligned,single-layer,planar spiral circular coils with a proposed geometric dimension,operating at a resonant frequency of 13.56 MHz.Both transmitter and receiver coils are small in size.Implanted device resistance varies from 200Ωto 500Ωwith 50Ωof stepes.When the conventional load resistance of power amplifiers is 50Ω,the efficiency is 45%;when the optimum resonant load is 41.89Ωwith a coupling coefficient of 0.087,the efficiency increases to 49%.The efficiency optimization is reached by calculating the matching network for the external LC tank of the transmitter coil.The proposed design may be suitable for active implantable devices.展开更多
Background: As the prognosis of lung cancer (LC) patients improves, subcutaneously implanted central venous access device ports (CV-ports) have frequently been used for continuing chemotherapy (CC) or palliative care ...Background: As the prognosis of lung cancer (LC) patients improves, subcutaneously implanted central venous access device ports (CV-ports) have frequently been used for continuing chemotherapy (CC) or palliative care (PC). In this study, we examined the clinical course of LC patients with subcutaneously implanted CV-ports from the time of receiving chemotherapy to the endpoint of cancer. Materials and Methods: We retrospectively reviewed the clinical data and treatment history of LC patients with subcutaneously implanted CV-ports between June 2008 and November 2013 using clinical records and a pharmacy database. Results: Of the 132 LC patients with subcutaneously implanted CV-ports, 79 (59.8%) had CV-ports for CC (the CC group) and 53 (40.2%) had CV-ports for PC (the PC group). After CV-port implantation, LC patients in the CC group received a median of two regimens with a median of 6 cycles. The median survival time of patients in the CC and PC groups was 457 and 44 days, respectively. In the CC group, the median survival time of small cell and non-small cell LC patients was 342 (95% confidence interval, 235 - 627) and 563 (95% confidence interval, 368 - 728) days, respectively. Nine patients (6.8%) had their CV-ports removed due to complications. Forty (30.3%) of the 132 enrolled patients were referred for at-home PC. The at-home death rate observed among these 40 patients was 30.0% (N = 12). Conclusion: CV-ports may contribute to seamless oncological care.展开更多
Implantable cardiovascular devices have revolutionized the management of cardiovascular diseases,significantly enhancing patients’quality of life.With the increasing demand of cardiac implantable electronic devices,t...Implantable cardiovascular devices have revolutionized the management of cardiovascular diseases,significantly enhancing patients’quality of life.With the increasing demand of cardiac implantable electronic devices,the imperative for novel device development is evident.This review article first elaborates the mechanisms underlying foreign body response and infection,elucidating the complex interplay between implanted constructs and host tissues.The discussion then focuses on current advancements in materials science and engineering aimed at mitigating these challenges.Material innovations,such as drugeluting materials,surface modifications,and biomimetic materials,are explored as strategies to modulate these responses and to prevent fibrotic or thrombotic complications and infection.Finally,future directions in materials development for implantable cardiovascular devices are introduced.By addressing safety and patency concerns through innovative material strategies,this article aims to guide the research and development of advanced materials for both current and future cardiovascular implantable devices,ultimately improving patient outcomes and advancing cardiovascular disease treatment.展开更多
Malignant tumors have the capability to metastasize and colonize,meaning that they can spread to other organs and tissues,distributing metastatic focus and are hard to target.Although significant advances have been ma...Malignant tumors have the capability to metastasize and colonize,meaning that they can spread to other organs and tissues,distributing metastatic focus and are hard to target.Although significant advances have been made in cancer treatment,it remains one of the leading causes of death around the globe.In recent years,new-emerging implantable systems and devices have been developed to tackle the challenge of metastatic tumors.In this review,implantable systems for suppressing tumors and preventing tumor recurrence are reported.In particular,we emphasize the responsive drug delivery systems and the external field assisted catalytic therapy for tumor treatment,as well as implantable biosensors for tumor microenvironment monitoring.We also conclude the open challenges and future perspectives of implantable systems and devices for cancer therapy and sensing.展开更多
Implantable electronic devices as a valuable biomedical tool are used to treat chronic diseases.However,traditional pacemakers exist a serious risk of complications.A biodegradable,closed‐loop sensor‐actuator system...Implantable electronic devices as a valuable biomedical tool are used to treat chronic diseases.However,traditional pacemakers exist a serious risk of complications.A biodegradable,closed‐loop sensor‐actuator system is developed for cardiac rhythm monitoring.This system could achieve autonomous electrotherapy.展开更多
Neural network functionality depends on the signaling of excitable cells and intricate synaptic connections,which collectively promote advanced functions of the brain,such as perception,motor control,and cognition.Neu...Neural network functionality depends on the signaling of excitable cells and intricate synaptic connections,which collectively promote advanced functions of the brain,such as perception,motor control,and cognition.Neurological diseases may cause changes in the structure and connection patterns of neural networks,thereby leading to loss of motor and sensory functions.Neural interfaces are dependable tools for recording or stimu-lating neural circuit dynamics,but conventional neural implants do not align with the physicochemical char-acteristics of living tissues,resulting in eventual failure of these interface devices.These challenges in neuroengineering have spurred progress in materials science.In this account,we explore the interaction mechanisms between electrodes and biological tissues,offering strategies to meet the electrochemical and biocompatibility demands of bioelectronic interfaces in engineering,with an emphasis on the structural design and manufacturing technologies of implantable devices.展开更多
Background：The conventional venous access for cardiovascular implantable electronic device （CIED） is the subclavian vein,which is often accompanied by high complication rate.The aim of this study was to assess the ...Background：The conventional venous access for cardiovascular implantable electronic device （CIED） is the subclavian vein,which is often accompanied by high complication rate.The aim of this study was to assess the efficacy and safety of optimized axillary vein technique.Methods：A total of 247 patients undergoing CIED implantation were included and assigned to the axillary vein group or the subclavian vein group randomly.Success rate of puncture and complications in the perioperative period and follow-ups were recorded.Results：The overall success rate （95.7% vs.96.0%） and one-time success rate （68.4% vs.66.1%） of punctures were similar between the two groups.In the subclavian vein group,pneumothorax occurred in three patients.The subclavian gaps of three patients were too tight to allow operation of the electrode lead.In contrast,there were no puncture-associated complications in the axillary vein group.In the patient follow-ups,two patients in the subclavian vein group had subclavian crush syndrome and both of them received lead replacement.The incidence of complications during the perioperative period and follow-ups of the axillary vein group and the subclavian vein group was 1.6% （2/125） and 8.2% （10/122）,respectively （χ^2=5.813,P =0.016）.Conclusion：Optimized axillary vein technique may be superior to the conventional subclavian vein technique for CIED lead placement.展开更多
Implantable electronic devices(IEDs)are widely used by human beings to achieve medical treatment and diagnosis nowadays.However,ideal encapsulation of IEDs is still far from perfect as full prevention of body fluid di...Implantable electronic devices(IEDs)are widely used by human beings to achieve medical treatment and diagnosis nowadays.However,ideal encapsulation of IEDs is still far from perfect as full prevention of body fluid diffusion into the coating remains unsolved.Herein,we develop a high-performance composite coating for IED encapsulation by introducing SiO_(2) nanoparticles into silicone rubber,which synergistically enhances mechanical properties and improves barrier performance.By fabricating composite coatings with different nanosilica contents,3%nanosilica is proved to be an optimal additive content with an excellent combination of improved fracture strength(from 2.5 MPa to 4.5 MPa),increased coating resistance(from 10^(4) to 10^(9) cm^(2))and ideal coating uniformity.Mechanical and electrochemical characterizations subsequently confirm substantially enhanced mechanical properties and barrier performance of the composite coating,which effectively resist crack propagation and impede penetrations of water and chloride ions through the coating.Theoretical calculations further uncover that modified SiO_(2) particles with enriched methyl groups endow a strong bridging effect to interact with silicone rubber monomer,which,together with anti-agglomeration property of methyl groups,contributes to a pronounced improvement in mechanical performance of nanosilica-filled silicone rubber.Benefitting from the enhanced mechanical and barrier properties,the as-fabricated nanosilica-filled silicone rubber demonstrates superior protection for the encapsulated circuits with a significantly improved lifetime(709.1 h)compared to that of circuits coated by pure silicone rubber(472.8 h)and bare circuit boards(1 h),which offers great values for packaging material design in future IED encapsulation.展开更多
A non-invasive software upgrade method for permanent implantable medical devices was developed to alleviate patients＇ suffering due to malfunctions because of software faults,which may cause serious adverse health co...A non-invasive software upgrade method for permanent implantable medical devices was developed to alleviate patients＇ suffering due to malfunctions because of software faults,which may cause serious adverse health consequences or require enhancements with new software.The programs distributed to the internal implantable pulse generator（IPG） from the external programmer have been developed so that the upgrade service program in the IPG is simplified with most complex functions executed by the external programmer.A bidirectional protocol including frame definition and transmission mode was designed to insure secure upgrades.A neuro-stimulator was used to verify the upgrade solution with no additional elements,to maintain the hardware reliability.This study emphasizes how to insure a secure and stable upgrade process and reduce power consumption for special wireless and life safety-critical applications.Tests on rhesus monkeys to evaluate the feasibility of the approach for an IPG used for brain stimulation evaluation show that the software upgrade can be implemented stably with good tolerance to the wireless data transmissions.展开更多
基金financially supported by the National Natural Science Foundation of China(U23A20591 and 52273158).
文摘Glioblastoma(GBM)is a highly infiltrative brain tumor.The treatment of GBM is challenging due to the existence of blood brain barrier,its highly invasive nature,and its heterogeneity.Given the limitations of conventional therapies,this Perspective explores the development trajectory of implantable devices,highlighting the advantages of current models.With the progression in research,these implantable devices certainly hold promising potential for GBM therapy.
文摘A common model of power supply for implantable devices was established to study factors affecting volume conduction energy transfer. Electromagnetic and equivalent circuit models were constructed to study the effect of separation between the source electrode pairs on volume conduction energy transfer. In addition, the parameters of external signal including waveform, amplitude and frequency were analyzed. As the current amplitude did not lead to tissue injury and the current frequency did not cause nerve excitability, the recommended separation be- tween the source electrodes was 3 cm, the proposed waveform of signal source was sinusoidal wave and the opti- mal frequency was 200 KHz. In agar experiment and swine skin experiment, the current transfer efficiencies were 28.13% and 20.65%, respectively, and the energy transfer efficiencies were 9.86% and 6.90%, respectively. In conclusion, we can achieve optimal efficiency of energy transfer by appropriately setting the separation between the source electrode parameters of the signal source.
文摘Background:Cardiac implantable electronic devices(CIEDs)are essential for preventing sudden cardiac death in patients with cardiovascular diseases,but implantation procedures carry risks of complications such as infection,hematoma,and bleeding,with incidence rates of 3–4%.Previous studies have examined individual risk factors separately,but integrated predictive models are lacking.We compared the predictive performance and interpretability of artificial neural network(ANN)and logistic regression models to evaluate their respective strengths in clinical risk assessment.Methods:This retrospective study analyzed data from 180 patients who underwent cardiac implantable electronic device(CIED)implantation in Taiwan between 2017 and 2018.To address class imbalance and enhance model training,the dataset was augmented to 540 records using the Synthetic Minority Oversampling Technique(SMOTE).A total of 13 clinical risk factors were evaluated(e.g.,age,body mass index(BMI),platelet count,left ventricular ejection fraction(LVEF),prothrombin time/international normalized ratio(PT/INR),hemoglobin(Hb),comorbidities,and antithrombotic use).Results:The most influential risk factors identified by the ANN model were platelet count,PT/INR,LVEF,Hb,and age.In the logistic regression analysis,reduced LVEF,lower hemoglobin levels,prolonged PT/INR,and lower BMI were significantly associated with an increased risk of complications.ANN model achieved a higher area under the curve(AUC=0.952)compared to the logistic regression model(AUC=0.802),indicating superior predictive performance.Additionally,the overall model quality was also higher for the ANN model(0.93)than for logistic regression(0.76).Conclusions:This study demonstrates that ANN models can effectively predict complications associated CIED procedures and identify critical preoperative risk factors.These findings support the use of ANN-based models for individualized risk stratification,enhancing procedural safety,improving patient outcomes,and potentially reducing healthcare costs associated with postoperative complications.
基金supported by National Natural Science Foundation of China(Grant No.10772121)
文摘To overcome some of the problems inherent in conventional heating aids such as low gain at high fi'equencies due to acoustic feedback,discomfort in occlusion of the extemal ear canal and so on,implantable middle ear hearing devices(IMEHDs)have been developed over the past two decades.For such kinds of IMEHDs,this paper presents the design of a floating mass piezoelectric actuator using a PMN-30%PT stack as a new type of vibrator.The proposed piezoelectric actuator consists of only three components of a piezoelectric stack,a metal case and a clamp.For the purpose of aiding the design of this actuator,a coupling biomechanics model of human middle ear and the piezoelectric actuator was constructed.This model was built based on a complete set of computerized tomography section images of a healthy volunteer's left ear by reverse engineering technology.The validity of this model was confirmed by comparing the motion of the tympanic membrane and stapes footplate obtained by this model with published experimental measurements on human temporal bones.It is shown that the designed actuator can be implanted on the incus long process by a simple surgical operation,and the stapes footplate displacement by its excitation at 10.5 V root-mean-square(RMS)voltage was equivalent to that from acoustic stimulation at 100 dB sound pressure level(SPL),which is adequate stimulation to the ossicular chain.The corresponding power consumption is 0.04 mW per volt of excitation at 1 kHz,which is low enough for the transducer to be used in an implantable middle ear device.
文摘With the widespread adoption of ultrasound guidance,Seldinger puncture techniques,and intracardiac electrical positioning technology for the placement of peripherally inserted central catheters in recent years,an increasing number of medical staff and patients now accept peripheral placement of totally implantable venous access devices(TIVADs)in the upper arm.This approach has the advantage of completely avoiding the risks of hemothorax,pneumothorax,and neck and chest scarring.Medical specialties presently engaged in this study in China include internal medicine,surgery,anesthesiology,and interventional departments.However,command over implantation techniques,treatment of complications,and proper use and maintenance of TIVAD remain uneven among different medical units.Moreover,currently,there are no established quality control standards for implantation techniques or specifications for handling complications.Thus,this expert consensus is proposed to improve the success rate of TIVAD implantation via the upper-arm approach,reduce complication rates,and ensure patient safety.This consensus elaborates on the technical indications and contraindications,procedures and technical points,treatment of complications,and the use and maintenance of upper-arm TIVAD,thus providing a practical reference for medical staff.
文摘Background Cardiac implantable electronic devices （CIEDs） greatly improve survival and life quality of patients. However, there are gender differences regarding both the utilization and benefit of these devices. In this prospective CIED registry, we aim to appraise the gender differences in CIED utilization in China. Methods Twenty centers from 14 provinces in China were included in our registry study. All patients who underwent a CIED implantation in these twenty centers between Jan 2015 and Dec 2016 were included. Results A total of 8570 patients were enrolled in the baseline cohort, including 7203 pacemaker, 664 implantable cardiac defibrillators （ICD） implants and 703 cardiac resynchronization therapy device （CRT/D）. Totally, 4117 （48.0%） CIED patients were female, and more than 59% pacemaker patients were female, but women account only one third of ICD or CRT/D implantation in this registry. There were significant differences between genders at pacemaker and ICD indications. Female was more likely received a pacemaker due to sick sinus syndrome （SSS） （63.9% vs. 51.0%, P 〈 0.001）. Female patients receiving an ICD were more likely due to cardiac ion channel disease （29.2% vs. 4.2%, P 〈 0.001）. The percentage of utilization of dual-chamber pacemaker in female patients was significantly higher than male （85.3% vs. 81.1%, P 〈 0.001）. But male patients were more likely received a cardiac resynchronization therapy devices with defibrillator than female （56.5% vs. 41.9%, P = 0.001）. In pacemaker patient, male was more likely to have structure heart disease （31.3% vs. 28.0%, P = 0.002）. In ICD patient, male patients were more likely to have ischemic heart disease （48.2% vs. 29.2%, P 〈 0.001）. The mean age of women at the time of CRT/D implantation was older than men （P = 0.014）. Nonischemic cardiomyopathy （70.9%） was the most common etiology in the patients who underwent the treat？ment of CRT/D, no matter male or female. Conclusions In real-world setting, female do have different epidemiology, pathophysiology and clinical presentation of many cardiac rhythm disorders when compared with male, and all these factors may affect the utilization of CIED implantation. But it also possibility that cultural and socioeconomic features may play a role in this apparent discrimination.
文摘As cardiac implantable electronic devices(CIED)become more prevalent,it is important to acknowledge potential electromagnetic interference(EMI)from other sources,such as internal and external electronic devices and procedures and its effect on these devices.EMI from other sources can potentially inhibit pacing and trigger shocks in permanent pacemakers(PPM)and implantable cardioverter defibrillators(ICD),respectively.This review analyzes potential EMI amongst CIED and left ventricular assist device,deep brain stimulators,spinal cord stimulators,transcutaneous electrical nerve stimulators,and throughout an array of procedures,such as endoscopy,bronchoscopy,and procedures involving electrocautery.Although there is evidence to support EMI from internal and external devices and during procedures,there is a lack of large multicenter studies,and,as a result,current management guidelines are based primarily on expert opinion and anecdotal experience.We aim to provide a general overview of PPM/ICD function,review documented EMI effect on these devices,and acknowledge current management of CIED interference.
文摘BACKGROUND Cardiovascular implantable electronic devices(CIEDs)are implanted in an increasing number of patients each year,which has led to an increase in the risk of CIED infection.Antibacterial CIED envelopes locally deliver antibiotics to the implant site over a short-term period and have been shown to reduce the risk of implant site infection.These envelopes are derived from either biologic or nonbiologic materials.There is a paucity of data examining patient risk profiles and outcomes from using these envelope materials in the clinical setting and comparing these results to patients receiving no envelope with their CIED implantation.AIM To evaluate risk profiles and outcomes of patients who underwent CIED procedures with an antibacterial envelope or no envelope.METHODS After obtaining Internal Review Board approval,the records of consecutive patients who underwent a CIED implantation procedure by a single physician between March 2017 and December 2019 were retrospectively collected from our hospital.A total of 248 patients within this period were identified and reviewed through 12 mo of follow up.The CIED procedures used either no envelope(n=57),a biologic envelope(CanGaroo®,Aziyo Biologics)that was pre-hydrated by the physician with vancomycin and gentamicin(n=89),or a non-biologic envelope(Tyrx^(TM),Medtronic)that was coated with a resorbable polymer containing the drug substances rifampin and minocycline by the manufacturer(n=102).Patient selection for receiving either no envelope or an envelope(and which envelope to use)was determined by the treating physician.Statistical analyses were performed between the 3 groups(CanGaroo,Tyrx,and no envelope),and also between the No Envelope and Any Envelope groups by an independent,experienced biostatistician.RESULTS On average,patients who received any envelope(biologic or non-biologic)were younger(70.7±14.0 vs 74.9±10.6,P=0.017),had a greater number of infection risk factors(81.2%vs 49.1%,P<0.001),received more high-powered devices(37.2%vs 5.8%,P=0.004),and were undergoing more reoperative procedures(47.1%vs 0.0%,P<0.001)than patients who received no envelope.Between the two envelopes,biologic envelopes tended to be used more often in higher risk patients(84.3%vs 78.4%)and reoperative procedures(62.9%vs 33.3%)than non-biologic envelopes.The rate of CIED implant site pocket infection was low(any envelope 0.5%vs no envelope 0.0%)and was statistically equivalent between the two envelope groups.Other reported adverse events(lead dislodgement,lead or pocket revision,device migration or erosion,twiddler’s syndrome,and erythema/fever)were low and statistically equivalent between groups(biologic 2.2%,non-biologic 3.9%,no envelope 1.8%).CONCLUSION CIED infection rates for biologic and non-biologic antibacterial envelopes are similar.Antibacterial envelopes may benefit patients who are higher risk for infection,however additional studies are warranted to confirm this.
文摘AIM:To compare the surgical outcomes of glaucoma drainage device implantation(GDI)and trans-scleral neodymium:YAG cyclophotocoagulation(CPC)in the management of refractory glaucoma after Descemetstripping automated endothelial keratoplasty(DSAEK).METHODS:This retrospective study on observational case series enrolled 29 patients who underwent DSAEK and posterior anti-glaucoma surgery(15 with GDI and 14 with CPC).The main outcome measures were intraocular pressure(IOP),glaucoma surgery success rate(defined as IOP of 6–21 mm Hg without additional anti-glaucoma operation),number of glaucoma medications,endothelial graft status,and best-corrected visual acuity(BCVA).RESULTS:The mean follow-up time was 34.1 and 21.0mo for DSAEK or glaucoma surgeries,both for the GDI and CPC groups.Both groups showed significant IOP reduction after glaucoma surgery.The GDI group presented a significantly higher success rate in IOP control than the CPC group(60%vs 21.4%,P=0.03).Both procedures significantly decreased the number of glaucoma medications(P=0.03).Forty percent and 57%of cases in the GDI and the CPC group,respectively,experienced endothelial graft failure during follow-up(P=0.36).Significantly worse BCVA after surgery was observed in the CPC group but not in the GDI group.CONCLUSION:Both GDI and CPC significantly decrease IOP in eyes with glaucoma after DSAEK.GDI is preferable to CPC in refractory glaucoma cases after DSAEK,as it manifests a significantly higher success rate for IOP control,similar endothelial graft failure rate,and relatively preserves BCVA than CPC.
文摘1 Introduction Virtually all cardiovascular diseases including arrhythmias,valve disease,coronary artery disease and heart failure(HF)are increasingly common with advancing age.^([1])Age and disease-related changes in the heart including fibrosis in the atrial and ventricular myocardium and conduction system,scar tissue from myocardial infarction or other cardiomyopathic processes,increased inflammatory cytokines and changes to ion channels are just some of the factors that predispose older adults to arrhythmias.^([2]).
基金the Grant Agency of the University of South Bohemia in Ceske Budejovice(project registration No.GAJU 079/2019/S)the Foundation Cardiac Center Ceske Budejovice for their financial support covering article processing and publication charges。
文摘Background Remote monitoring(RM)is increasingly employed for all types of cardiac implantable devices(CIED).However,there are only limited data on the acceptance of RM by the elderly.The aim of our study was to ascertain how octogenarians assess RM technologies compared to younger,presumably technically more literate patients,and what concerns or technical problems the system presents to both groups of patients.Methods The trial was designed as a descriptive,register-based single-center study.The study population consisted of all consecutive patients≥80 years of age(group A,n=94)and all consecutive patients aged≤40 years(group B,n=71),who had undergone implantation of an implantable cardioverter-defibrillator(ICD)between the years of 2009 and 2018 and were using a Home Monitoring?(HM,Biotronik,Berlin,Germany)system.All patients fulfilling entry criteria were approached with a request to participate in the survey.Results A total of 85(90.4%)and 65(91.5%)valid surveys were obtained for groups A and B,respectively.Ninety-two percent of patients in both groups(P=0.903)were satisfied with the limited number of planned ambulatory follow-ups(i.e.,once a year).All patients in both groups(100%)reported that they were satisfied with the HM system,and 97%and 94%of patients in Groups A and B,respectively,ranked it highly beneficial(P=0.68).A significant proportion of patients in both groups were completely unaware of any health-related benefits associated with the use of the HM system(42%in Group A vs.49%in Group B,P=0.4).Among the most frequently reported personal benefits of HM were a sense of safety and security and savings on travel expenses and time.5%and 9%of patients in Groups A and B,respectively,reported that usage of HM caused them some degree of psychological stress(P=0.27).Nearly all patients in both groups reported receiving information on HM from their doctor after ICD implantation.None of Group A reported receiving information from a nurse either before or after ICD implantation,while 14%of Group B patients reported receiving information from a nurse after,but not before ICD implantation.Seven and 51%(P<0.0001)of patients in Group A and B,respectively,sought additional information about HM post-discharge.Conclusions The HM system received good marks and was much appreciated,even in patients over 80 years of age.The level of acceptance and potential psychological stress resulting from RM technology appears to be about the same in older patients as in younger patients.The majority of octogenarians either did not fully understand the clinical benefits of the system or mistakenly thought that the HM system was a substitute for emergency 24-h surveillance.These results highlight the need for better patient education relative to RM technology,with one option being to delegate more of this educational process to specially trained nurses.
文摘Recently,the inductive coupling link is the most robust method for powering implanted biomedical devices,such as micro-system stimulators,cochlear implants,and retinal implants.This research provides a novel theoretical and mathematical analysis to optimize the inductive coupling link efficiency driven by efficient proposed class-E power amplifiers using high and optimum input impedance.The design of the coupling link is based on two pairs of aligned,single-layer,planar spiral circular coils with a proposed geometric dimension,operating at a resonant frequency of 13.56 MHz.Both transmitter and receiver coils are small in size.Implanted device resistance varies from 200Ωto 500Ωwith 50Ωof stepes.When the conventional load resistance of power amplifiers is 50Ω,the efficiency is 45%;when the optimum resonant load is 41.89Ωwith a coupling coefficient of 0.087,the efficiency increases to 49%.The efficiency optimization is reached by calculating the matching network for the external LC tank of the transmitter coil.The proposed design may be suitable for active implantable devices.
文摘Background: As the prognosis of lung cancer (LC) patients improves, subcutaneously implanted central venous access device ports (CV-ports) have frequently been used for continuing chemotherapy (CC) or palliative care (PC). In this study, we examined the clinical course of LC patients with subcutaneously implanted CV-ports from the time of receiving chemotherapy to the endpoint of cancer. Materials and Methods: We retrospectively reviewed the clinical data and treatment history of LC patients with subcutaneously implanted CV-ports between June 2008 and November 2013 using clinical records and a pharmacy database. Results: Of the 132 LC patients with subcutaneously implanted CV-ports, 79 (59.8%) had CV-ports for CC (the CC group) and 53 (40.2%) had CV-ports for PC (the PC group). After CV-port implantation, LC patients in the CC group received a median of two regimens with a median of 6 cycles. The median survival time of patients in the CC and PC groups was 457 and 44 days, respectively. In the CC group, the median survival time of small cell and non-small cell LC patients was 342 (95% confidence interval, 235 - 627) and 563 (95% confidence interval, 368 - 728) days, respectively. Nine patients (6.8%) had their CV-ports removed due to complications. Forty (30.3%) of the 132 enrolled patients were referred for at-home PC. The at-home death rate observed among these 40 patients was 30.0% (N = 12). Conclusion: CV-ports may contribute to seamless oncological care.
基金supported by the National Heart,Lung,and Blood Institute of the National Institutes of Health under Award(No.R01HL157077).
文摘Implantable cardiovascular devices have revolutionized the management of cardiovascular diseases,significantly enhancing patients’quality of life.With the increasing demand of cardiac implantable electronic devices,the imperative for novel device development is evident.This review article first elaborates the mechanisms underlying foreign body response and infection,elucidating the complex interplay between implanted constructs and host tissues.The discussion then focuses on current advancements in materials science and engineering aimed at mitigating these challenges.Material innovations,such as drugeluting materials,surface modifications,and biomimetic materials,are explored as strategies to modulate these responses and to prevent fibrotic or thrombotic complications and infection.Finally,future directions in materials development for implantable cardiovascular devices are introduced.By addressing safety and patency concerns through innovative material strategies,this article aims to guide the research and development of advanced materials for both current and future cardiovascular implantable devices,ultimately improving patient outcomes and advancing cardiovascular disease treatment.
基金supported by the National Nature Science Foundation of China(Nos.82072065 and 82202333)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA16021103)+2 种基金the Fundamental Research Funds for the Central Universities(Nos.E2EG6802X2 and E2E46801)the China Postdoctoral Science Foundation(Nos.BX2021299 and 2021M703166)the National Youth Talent Support Program.
文摘Malignant tumors have the capability to metastasize and colonize,meaning that they can spread to other organs and tissues,distributing metastatic focus and are hard to target.Although significant advances have been made in cancer treatment,it remains one of the leading causes of death around the globe.In recent years,new-emerging implantable systems and devices have been developed to tackle the challenge of metastatic tumors.In this review,implantable systems for suppressing tumors and preventing tumor recurrence are reported.In particular,we emphasize the responsive drug delivery systems and the external field assisted catalytic therapy for tumor treatment,as well as implantable biosensors for tumor microenvironment monitoring.We also conclude the open challenges and future perspectives of implantable systems and devices for cancer therapy and sensing.
基金Ministry of Science and Technology of China,Grant/Award Number:2018YFA0703200National Natural Science Foundation of China,Grant/Award Number:51973154+2 种基金National Innovation Group“Organic Integrated Circuit Core Material Foundation”,Grant/Award Number:52121002Natural Science Foundation of Tianjin,Grant/Award Number:20JCZDJC00680Haihe Laboratory of Sustainable Chemical Transformations。
文摘Implantable electronic devices as a valuable biomedical tool are used to treat chronic diseases.However,traditional pacemakers exist a serious risk of complications.A biodegradable,closed‐loop sensor‐actuator system is developed for cardiac rhythm monitoring.This system could achieve autonomous electrotherapy.
基金supported by grants from the National Innovation Platform Develop-ment Program(No.2020021105012440)the National Natural Science Foundation of China(No.82172524,81974355)+1 种基金the Major Pro-gram of Hubei Province(No.2023BAA005)Key Research and Devel-opment Program Project of Hubei Province(NO.2021BEA161).
文摘Neural network functionality depends on the signaling of excitable cells and intricate synaptic connections,which collectively promote advanced functions of the brain,such as perception,motor control,and cognition.Neurological diseases may cause changes in the structure and connection patterns of neural networks,thereby leading to loss of motor and sensory functions.Neural interfaces are dependable tools for recording or stimu-lating neural circuit dynamics,but conventional neural implants do not align with the physicochemical char-acteristics of living tissues,resulting in eventual failure of these interface devices.These challenges in neuroengineering have spurred progress in materials science.In this account,we explore the interaction mechanisms between electrodes and biological tissues,offering strategies to meet the electrochemical and biocompatibility demands of bioelectronic interfaces in engineering,with an emphasis on the structural design and manufacturing technologies of implantable devices.
文摘Background：The conventional venous access for cardiovascular implantable electronic device （CIED） is the subclavian vein,which is often accompanied by high complication rate.The aim of this study was to assess the efficacy and safety of optimized axillary vein technique.Methods：A total of 247 patients undergoing CIED implantation were included and assigned to the axillary vein group or the subclavian vein group randomly.Success rate of puncture and complications in the perioperative period and follow-ups were recorded.Results：The overall success rate （95.7% vs.96.0%） and one-time success rate （68.4% vs.66.1%） of punctures were similar between the two groups.In the subclavian vein group,pneumothorax occurred in three patients.The subclavian gaps of three patients were too tight to allow operation of the electrode lead.In contrast,there were no puncture-associated complications in the axillary vein group.In the patient follow-ups,two patients in the subclavian vein group had subclavian crush syndrome and both of them received lead replacement.The incidence of complications during the perioperative period and follow-ups of the axillary vein group and the subclavian vein group was 1.6% （2/125） and 8.2% （10/122）,respectively （χ^2=5.813,P =0.016）.Conclusion：Optimized axillary vein technique may be superior to the conventional subclavian vein technique for CIED lead placement.
基金supported by the National Natural Science Foundation of China(Nos.51871227 and 52271079).
文摘Implantable electronic devices(IEDs)are widely used by human beings to achieve medical treatment and diagnosis nowadays.However,ideal encapsulation of IEDs is still far from perfect as full prevention of body fluid diffusion into the coating remains unsolved.Herein,we develop a high-performance composite coating for IED encapsulation by introducing SiO_(2) nanoparticles into silicone rubber,which synergistically enhances mechanical properties and improves barrier performance.By fabricating composite coatings with different nanosilica contents,3%nanosilica is proved to be an optimal additive content with an excellent combination of improved fracture strength(from 2.5 MPa to 4.5 MPa),increased coating resistance(from 10^(4) to 10^(9) cm^(2))and ideal coating uniformity.Mechanical and electrochemical characterizations subsequently confirm substantially enhanced mechanical properties and barrier performance of the composite coating,which effectively resist crack propagation and impede penetrations of water and chloride ions through the coating.Theoretical calculations further uncover that modified SiO_(2) particles with enriched methyl groups endow a strong bridging effect to interact with silicone rubber monomer,which,together with anti-agglomeration property of methyl groups,contributes to a pronounced improvement in mechanical performance of nanosilica-filled silicone rubber.Benefitting from the enhanced mechanical and barrier properties,the as-fabricated nanosilica-filled silicone rubber demonstrates superior protection for the encapsulated circuits with a significantly improved lifetime(709.1 h)compared to that of circuits coated by pure silicone rubber(472.8 h)and bare circuit boards(1 h),which offers great values for packaging material design in future IED encapsulation.
基金Supported in part by the National Key Technology Research andDevelopment Program (No 2009BAI79B03)in part by the National Natural Science Foundation of China (No 60906050/F040604)the Opening Foundation of the State Key Laboratory of Space Medicine Fundamentals and Application (Chinese Astronaut Research and Training Center) (No SMFA09K08)
文摘A non-invasive software upgrade method for permanent implantable medical devices was developed to alleviate patients＇ suffering due to malfunctions because of software faults,which may cause serious adverse health consequences or require enhancements with new software.The programs distributed to the internal implantable pulse generator（IPG） from the external programmer have been developed so that the upgrade service program in the IPG is simplified with most complex functions executed by the external programmer.A bidirectional protocol including frame definition and transmission mode was designed to insure secure upgrades.A neuro-stimulator was used to verify the upgrade solution with no additional elements,to maintain the hardware reliability.This study emphasizes how to insure a secure and stable upgrade process and reduce power consumption for special wireless and life safety-critical applications.Tests on rhesus monkeys to evaluate the feasibility of the approach for an IPG used for brain stimulation evaluation show that the software upgrade can be implemented stably with good tolerance to the wireless data transmissions.
