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Therapeutic Methods and Therapies TCIM
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1.
Adv Ther ; 37(2): 637-643, 2020 02.
Article in English | MEDLINE | ID: mdl-31875299

ABSTRACT

Recently rechargeable devices have been introduced for sacral neuromodulation (SNM) with conditional safety for full-body magnetic resonance imaging (MRI). Currently a recharge-free SNM device represents the standard implant; however, it is only approved for MRI head scans. As further new technologies with broader MRI capabilities are emerging, the advantages as well as disadvantages of both rechargeable versus recharge-free devices will be briefly discussed in this commentary from the perspective of patients, healthcare professionals, and providers.


Subject(s)
Fecal Incontinence/therapy , Inventions , Prostheses and Implants/standards , Sacrum/physiopathology , Therapies, Investigational/standards , Transcutaneous Electric Nerve Stimulation/standards , Urinary Bladder, Overactive/therapy , Adult , Aged , Aged, 80 and over , Female , Guidelines as Topic , Humans , Male , Middle Aged , Therapies, Investigational/instrumentation , Therapies, Investigational/methods , Transcutaneous Electric Nerve Stimulation/instrumentation , Transcutaneous Electric Nerve Stimulation/methods
2.
Rev Bras Enferm ; 71(3): 1099-1105, 2018 May.
Article in Portuguese, English | MEDLINE | ID: mdl-29924168

ABSTRACT

OBJECTIVE: to assess potential failures in the care process with orthotics, prosthetics and special materials in a high-complexity hospital. METHOD: an intervention study conducted from March to October 2013. This process was assessed with the Failure Mode and Effects Analysis (FMEA) service tool. The data were analysed according to the risk and the corrective measures were defined. RESULTS: no failure was classified as high risk and the corrective measures indicated as low and moderate risk had the following improvement initiatives suggested: standardize the material records in the information system; create a specific form to require materials; hire specialized technical personnel and create a continuous education program. CONCLUSION: all the suggested initiatives were implemented and helped to reduce the assistance risks for patients due to failures in this process. The actions increase safety levels and provide higher quality of service.


Subject(s)
Nursing Care/standards , Orthotic Devices/standards , Prostheses and Implants/standards , Risk Assessment/methods , Brazil , Humans , Medical Errors/prevention & control , National Health Programs/organization & administration
3.
Rev. bras. enferm ; Rev. bras. enferm;71(3): 1099-1105, May-June 2018. graf
Article in English | LILACS, BDENF - Nursing | ID: biblio-958640

ABSTRACT

ABSTRACT Objective: to assess potential failures in the care process with orthotics, prosthetics and special materials in a high-complexity hospital. Method: an intervention study conducted from March to October 2013. This process was assessed with the Failure Mode and Effects Analysis (FMEA) service tool. The data were analysed according to the risk and the corrective measures were defined. Results: no failure was classified as high risk and the corrective measures indicated as low and moderate risk had the following improvement initiatives suggested: standardize the material records in the information system; create a specific form to require materials; hire specialized technical personnel and create a continuous education program. Conclusion: all the suggested initiatives were implemented and helped to reduce the assistance risks for patients due to failures in this process. The actions increase safety levels and provide higher quality of service.


RESUMEN Objetivo: evaluar las fallas potenciales en el proceso de trabajo del cuidado con ortesis, prótesis y materiales especiales en un hospital de alta complejidad. Método: estudio de intervención realizado de marzo a octubre de 2013. El proceso fue evaluado utilizando la herramienta de Análisis del Modo y Efecto de Fallas del tipo servicio. Los datos fueron analizados conforme el riesgo y se definieron las medidas correctivas. Resultados: ninguna falla fue clasificada como alto riesgo y las medidas correctivas apuntadas como de bajo y moderado riesgo han tenido propuestas de acciones de perfeccionamiento: estandarización de los registros de materiales en el sistema de información; creación de un formulario específico para la solicitud de material; contratación de personal técnico especializado y creación de un programa de educación permanente. Conclusión: todas las acciones propuestas fueron implantadas y ayudaron en la reducción del riesgo asistencial a los pacientes por fallas en este proceso, aumentando los niveles de seguridad y proporcionando más calidad en el servicio.


RESUMO Objetivo: avaliar as falhas potenciais, no processo de trabalho do cuidado com órteses, próteses e materiais especiais em um hospital de alta complexidade. Método: estudo de intervenção realizado de março a outubro de 2013. O processo foi avaliado utilizando a ferramenta de Análise de Modos de Falhas e Efeitos do tipo serviço. Os dados foram analisados conforme o risco e foram definidas as medidas corretivas. Resultados: nenhuma falha foi classificada de alto risco e as medidas corretivas apontadas como de baixo e moderado risco tiveram propostas de ações de melhoria, como: padronização dos cadastros de materiais no sistema de informação; criação de um formulário específico para a solicitação de material; contratação de pessoal técnico especializado e criação de um programa de educação permanente. Conclusão: todas as ações propostas foram implantadas e auxiliaram na redução do risco assistencial aos pacientes por falhas neste processo, aumentando os níveis de segurança e proporcionando maior qualidade no serviço.


Subject(s)
Humans , Orthotic Devices/standards , Prostheses and Implants/standards , Risk Assessment/methods , Nursing Care/standards , Brazil , Medical Errors/prevention & control , National Health Programs/organization & administration
4.
Rev. bras. cir. plást ; 31(3): 299-307, 2016. ilus
Article in English, Portuguese | LILACS | ID: biblio-2292

ABSTRACT

INTRODUÇÃO: A pele de pacientes emagrecidas pós-cirurgia bariátrica apresenta alterações estruturais e proteômicas e não resiste ao peso das mamas, levando-as à flacidez residual precoce, exigindo suporte auxiliar. O objetivo é aplicar suporte auxiliar de lâmina de polipropileno não absorvível mais poliglecaprone absorvível ou lâmina de silicone de bustos, em forma de "soutien interno" como auxiliar de sustentação da pele, para manutenção da forma das mamas, e flacidez no mínimo comparável a outras pacientes sem emagrecimento pela cirurgia bariátrica. MÉTODOS: Nove pacientes foram submetidas à mamoplastia em T invertido com modelagem dos tecidos mamários, com redução do volume e envolvidos com lâmina de sustentação auxiliar. RESULTADOS: Não houve flacidez precoce e em observação de até 4 anos ela era aceitável. Uma delas apresentou seroma, drenado com boa resolução. Serão operadas outras 24 pacientes dentro do protocolo, acompanhadas e observadas por 2 anos com controle mamográfico, ultrassônico e ressonância magnética. CONCLUSÃO: A mamoplastia redutora pós-cirurgia bariátrica requer suporte extra à glândula mamária. A pele estruturalmente alterada não suporta o seu peso e haverá flacidez precoce.


INTRODUCTION: The skin presents structural and proteomic changes after bariatric surgery and cannot withstand the weight of the breasts, which leads to early residual flaccidity, requiring auxiliary support. The goal is to apply a nonabsorbable polypropylene-poliglecaprone absorbable auxiliary mesh support or Bustos silicone sheet, in the form of an "internal brassiere," to support the skin in order to maintain the shape and flaccidity of the breasts comparable with those of normal breasts. METHODS: Nine patients underwent mammoplasty in inverted T with modeling of tissue implants, reduction of breast volume, and wrapping with an auxiliary support mesh. RESULTS: Flaccidity was not observed at an early stage and the condition was acceptable for up to 4 years of follow-up. One of the patients had a seroma, which was drained with good resolution. Another 24 patients will be operated according to the protocol and observed for 2 years by using mammography, ultrasonography, and magnetic resonance imaging. CONCLUSION: Reduction mammoplasty after bariatric surgery requires additional support for the mammary gland. The structurally altered skin could not support the weight of the breasts, resulting in early flaccidity.


Subject(s)
Humans , Female , Middle Aged , History, 21st Century , Polypropylenes , Prostheses and Implants , Obesity, Morbid , Breast , Weight Loss , Mammary Glands, Human , Bariatric Surgery , Polypropylenes/adverse effects , Polypropylenes/therapeutic use , Prostheses and Implants/adverse effects , Prostheses and Implants/standards , Obesity, Morbid/surgery , Obesity, Morbid/pathology , Obesity, Morbid/therapy , Breast/surgery , Breast/transplantation , Mammary Glands, Human/surgery , Mammary Glands, Human/transplantation , Bariatric Surgery/adverse effects , Bariatric Surgery/methods
5.
Perm J ; 16(2): 36-44, 2012.
Article in English | MEDLINE | ID: mdl-22745614

ABSTRACT

INTRODUCTION: Considering the high cost, volume, and patient safety issues associated with medical devices, monitoring of medical device performance is critical to ensure patient safety and quality of care. The purpose of this article is to describe the Kaiser Permanente (KP) implant registries and to highlight the benefits of these implant registries on patient safety, quality, cost effectiveness, and research. METHODS: Eight KP implant registries leverage the integrated health care system's administrative databases and electronic health records system. Registry data collected undergo quality control and validation as well as statistical analysis. RESULTS: Patient safety has been enhanced through identification of affected patients during major recalls, identification of risk factors associated with outcomes of interest, development of risk calculators, and surveillance programs for infections and adverse events. Effective quality improvement activities included medical center- and surgeon-specific profiles for use in benchmarking reports, and changes in practice related to registry information output. Among the cost-effectiveness strategies employed were collaborations with sourcing and contracting groups, and assistance in adherence to formulary device guidelines. Research studies using registry data included postoperative complications, resource utilization, infection risk factors, thromboembolic prophylaxis, effects of surgical delay on concurrent injuries, and sports injury patterns. CONCLUSIONS: The unique KP implant registries provide important information and affect several areas of our organization, including patient safety, quality improvement, cost-effectiveness, and research.


Subject(s)
Databases, Factual , Prostheses and Implants/standards , Registries/statistics & numerical data , California , Cost-Benefit Analysis , Humans , Patient Safety , Prostheses and Implants/adverse effects , Prostheses and Implants/economics , Quality Improvement , Research , Risk Assessment , Risk Factors
6.
Exp Brain Res ; 218(3): 389-400, 2012 May.
Article in English | MEDLINE | ID: mdl-22349559

ABSTRACT

An implantable prosthesis that stimulates vestibular nerve branches to restore sensation of head rotation and vision-stabilizing reflexes could benefit individuals disabled by bilateral loss of vestibular sensation. The normal vestibular system encodes head movement by increasing or decreasing firing rate of the vestibular afferents about a baseline firing rate in proportion to head rotation velocity. Our multichannel vestibular prosthesis emulates this encoding scheme by modulating pulse rate and pulse current amplitude above and below a baseline stimulation rate (BSR) and a baseline stimulation current. Unilateral baseline prosthetic stimulation that mimics normal vestibular afferent baseline firing results in vestibulo-ocular reflex (VOR) eye responses with a wider range of eye velocity in response to stimuli modulated above baseline (excitatory) than below baseline (inhibitory). Stimulus modulation about higher than normal baselines resulted in increased range of inhibitory eye velocity, but decreased range of excitatory eye velocity. Simultaneous modulation of rate and current (co-modulation) above all tested baselines elicited a significantly wider range of excitatory eye velocity than rate or current modulation alone. Time constants associated with the recovery of VOR excitability following adaptation to elevated BSRs implicate synaptic vesicle depletion as a possible mechanism for the small range of excitatory eye velocity elicited by rate modulation alone. These findings can be used toward selecting optimal baseline levels for vestibular stimulation that would result in large inhibitory eye responses while maintaining a wide range of excitatory eye velocity via co-modulation.


Subject(s)
Electric Stimulation Therapy/methods , Head Movements/physiology , Postural Balance/physiology , Prostheses and Implants/standards , Reflex, Vestibulo-Ocular/physiology , Vestibular Diseases/therapy , Animals , Chinchilla , Electrodes, Implanted/standards , Electrodes, Implanted/trends , Prostheses and Implants/trends , Vestibular Diseases/physiopathology
7.
BMC Musculoskelet Disord ; 12: 32, 2011 Feb 01.
Article in English | MEDLINE | ID: mdl-21284879

ABSTRACT

BACKGROUND: Total hip replacement is considered the best option for treatment of displaced intracapsular fractures of the femoral neck (FFN). The size of the femoral head is an important factor that influences the outcome of a total hip arthroplasty (THA): implants with a 28 mm femoral head are more prone to dislocate than implants with a 32 mm head. Obviously, a large head coupled to a polyethylene inlay can lead to more wear, osteolysis and failure of the implant. Ceramic induces less friction and minimal wear even with larger heads. METHODS: A total of 35 THAs were performed for displaced intracapsular FFN, using a 32 mm alumina-alumina coupling. RESULTS: At a mean follow-up of 80 months, 33 have been clinically and radiologically reviewed. None of the implants needed revision for any reason, none of the cups were considered to have failed, no dislocations nor breakage of the ceramic components were recorded. One anatomic cementless stem was radiologically loose. CONCLUSIONS: On the basis of our experience, we suggest that ceramic-on-ceramic coupling offers minimal friction and wear even with large heads.


Subject(s)
Aluminum Oxide/therapeutic use , Arthroplasty, Replacement, Hip/instrumentation , Femoral Neck Fractures/surgery , Prostheses and Implants/standards , Prosthesis Implantation/instrumentation , Aged , Arthroplasty, Replacement, Hip/methods , Female , Femoral Neck Fractures/diagnostic imaging , Femoral Neck Fractures/pathology , Humans , Male , Middle Aged , Prosthesis Implantation/methods , Radiography
9.
Acta Neurochir (Wien) ; 151(12): 1663-72, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19618104

ABSTRACT

BACKGROUND: The advent of stent-assisted coil embolization has revolutionized the endovascular management of complex intracranial aneurysms. Although performed routinely in most cerebrovascular centers, there are not many case series reported about the Y-stent technique for coil placement in cerebral aneurysms. The authors present the second largest series available within the neurosurgical literature. METHODS: The authors have retrospectively reviewed the medical records and angiographic data of six patients who were diagnosed as having unruptured cerebral aneurysms and subsequently treated using "Y" stent-assisted coil embolization. Five out of six cerebral aneurysms in this study were located at the basilar tip while the remaining one was at the left MCA trifurcation. Aneurysms ranged in size from 8-22 mm. All patients were female with ages ranging from 37-70 years. One patient presented with recurrence of an aneurysm previously managed with a balloon-assisted coil embolization. Another patient presented after a failed trial of a balloon-assisted procedure. One patient had originally been diagnosed with multiple aneurysms of varying size and location. RESULTS: A "Y" configuration was successfully established in all six patients. Five patients have had a symptom-free recovery period at average follow-up period of 36.7 months. The remaining patient is notable for recurrence that was discovered on angiogram 32 months postoperatively. CONCLUSIONS: The proposed Y-stent technique is a safe and effective option that can be employed in the endovascular reconstruction of unruptured intracranial aneurysms of complex location and orientation. These methods serve as an acceptable alternative in the management of aneurysms traditionally managed with microsurgery. Hemodynamic assessment has shown Y-stenting to be an advantageous therapy option, yet further studies are required to assess these parameters in alternative therapies.


Subject(s)
Embolization, Therapeutic/instrumentation , Intracranial Aneurysm/therapy , Prostheses and Implants/standards , Stents/standards , Adult , Aged , Cerebral Angiography , Embolization, Therapeutic/methods , Female , Humans , Intracranial Aneurysm/diagnostic imaging , Intracranial Aneurysm/pathology , Middle Aged , Retrospective Studies
10.
Minim Invasive Neurosurg ; 51(4): 208-10, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18683111

ABSTRACT

Day surgery awake craniotomy has been recently proposed for patients harbouring supratentorial brain tumours. This technique has been demonstrated to be safe and effective in a large cohort of patients operated by one neurosurgeon at the University of Toronto. The aim of this paper is to present a technical description of the protocol that has been adopted for these patients and a discussion of relevant practical issues which may arise. In particular, patient eligibility criteria are briefly discussed and intra- and post-operative management are presented. Key messages for those who are going to start to perform day surgery awake craniotomies include the preparation of a fast, simple and standardized protocol for the treatment of these patients and cooperation among patients and their care-givers (surgeon, anesthetist, nurses, family members).


Subject(s)
Ambulatory Surgical Procedures/methods , Brain Neoplasms/surgery , Clinical Protocols/standards , Craniotomy/methods , Neurosurgical Procedures/methods , Anesthesia, Local/methods , Bone Plates/standards , Brain/pathology , Brain/surgery , Humans , Hypnotics and Sedatives/administration & dosage , Neuronavigation/methods , Outpatients , Pain, Postoperative/drug therapy , Pain, Postoperative/prevention & control , Patient Care Team/standards , Patient Compliance , Patient Selection , Postoperative Care/methods , Preoperative Care/instrumentation , Preoperative Care/methods , Prostheses and Implants/standards , Surgical Flaps/standards , Wakefulness/drug effects
11.
Spine (Phila Pa 1976) ; 32(15): 1621-8, 2007 Jul 01.
Article in English | MEDLINE | ID: mdl-17621209

ABSTRACT

STUDY DESIGN: Prospective cohort follow-up study. OBJECTIVES: To refine the indication criteria for neuroreflexotherapy (NRT) in the treatment of subacute and chronic neck (NP), thoracic (TP) and low back pain (LBP) in the Spanish National Health Service (SNHS), by identifying prognostic factors for clinical outcome. SUMMARY OF BACKGROUND DATA: NRT consists of the temporary subcutaneous implantation of surgical devices in trigger points. Previous randomized controlled trials have shown its efficacy, effectiveness, and cost-effectiveness for treating subacute and chronic LBP. Clinical audits in routine practice have shown similar results in NP, TP, and LBP patients. PATIENTS AND METHODS: All 1514 patients from the SNHS in the Balearic Islands in which a NRT intervention was performed and who were discharged between January 1, 2004, and December 31, 2005, were included in this study. Treatment failure was defined as a baseline score equivalent to or lower than the corresponding one at discharge for local pain, referred pain, or LBP-related disability. Multivariate logistic regression models were developed for each of those variables. Maximal models included reason for referral (NP, TP, or LBP), age, sex, baseline values for each variable, number of days in which the surgical devices used in NRT were left implanted, duration of the current episode, time elapsed since the first episode, and previous failed surgery for the current episode. Calibration of the models was assessed through the Hosmer-Lemeshow test, while discrimination was assessed through the area under the ROC curve and the Nagelkerke R test. RESULTS: When referred to NRT, patients' median (IQR) duration of the episode was 210 (90, 730) days. Failure rates ranged between 9.9% for local pain and 14.5% for disability. Variables associated with a worst prognosis for local pain, referred pain, and disability were surgical devices remaining implanted for a shorter duration and, especially, a longer pain duration. Patients referred for NP were more likely to improve than those referred for TP or LBP. Regarding the evolution of local and referred pain, lesser improvement was observed in the least severe complaint at baseline. Models showed a good calibration. The area under the ROC curve ranged between 0.719 and 0.804, and R ranged between 0.101 and 0.255. CONCLUSION: A longer duration of the current episode is the worst detected prognostic factor for response to NRT, but prognostic models are inaccurate for predicting the clinical outcome of a given patient. In order to improve the success rate of this technology, these results only support earlier referral for patients complying with current indication criteria.


Subject(s)
Back Pain/therapy , Muscle, Skeletal/surgery , Myofascial Pain Syndromes/therapy , Neck Pain/therapy , Prostheses and Implants/statistics & numerical data , Reflexotherapy/methods , Adult , Aged , Back Pain/physiopathology , Chronic Disease/therapy , Cohort Studies , Female , Follow-Up Studies , Humans , Male , Middle Aged , Muscle, Skeletal/innervation , Muscle, Skeletal/physiopathology , Myofascial Pain Syndromes/physiopathology , National Health Programs , Neck Pain/physiopathology , Pain Measurement , Prognosis , Prospective Studies , Prostheses and Implants/standards , Reflexotherapy/instrumentation , Reflexotherapy/statistics & numerical data , Spain , Sutures/standards , Sutures/statistics & numerical data , Time Factors , Treatment Failure , Treatment Outcome
12.
Neurosci Lett ; 406(1-2): 81-6, 2006 Oct 02.
Article in English | MEDLINE | ID: mdl-16905255

ABSTRACT

Chronically implanted microelectrodes have been an important tool used by neuroscientists for many years and are critical for the development of neural prostheses designed to restore function after traumatic central nervous system (CNS) injury. It is well established that a variety of mammals, including non-human primates (NHP), tolerate noble metal electrodes in the cortex for extended periods of time, but little is known about the long-term effects of electrode implantation at the cellular level. While data from rodents have clearly shown gliosis around such implants, there have been difficulties in demonstrating these reactions in NHP. Glial reactions are to be expected in NHP, since any trauma to the mammalian CNS is believed to result in the formation of a glial scar consisting of reactive astrocytes and microglia around the injury site. Because a glial scar can potentially affect the quality of recordings or stimulations from implanted electrodes, it is important to determine the extent of gliosis around implants in NHP. We studied the response of cortical glial cells to chronic electrode implantation in the motor cortices of Rhesus macaques (Macaca mulatta) after 3 months and 3 years duration. Antibodies specific for astrocytes and microglia were used to detect the presence of glial reactions around electrode implant sites. Reactive glia were found within the cortical neuropil surrounding the chronically implanted noble metal electrodes. Reactive gliosis persisted over the time periods studied and demonstrates the importance of developing strategies to minimize this event, even around noble metal implants.


Subject(s)
Electric Stimulation Therapy/adverse effects , Gliosis/etiology , Macaca mulatta/surgery , Motor Cortex/injuries , Motor Cortex/pathology , Stereotaxic Techniques/adverse effects , Animals , Astrocytes/cytology , Astrocytes/physiology , Biomarkers/metabolism , Cicatrix/etiology , Cicatrix/physiopathology , Electric Stimulation Therapy/instrumentation , Electrodes, Implanted/adverse effects , Gliosis/physiopathology , Metals/toxicity , Microglia/cytology , Microglia/physiology , Motor Cortex/surgery , Nerve Degeneration/etiology , Nerve Degeneration/physiopathology , Nerve Tissue Proteins/metabolism , Neurons/pathology , Prostheses and Implants/adverse effects , Prostheses and Implants/standards , Stereotaxic Techniques/instrumentation , Time , Time Factors
13.
J Clin Neurosci ; 12(5): 574-9, 2005 Jun.
Article in English | MEDLINE | ID: mdl-16051097

ABSTRACT

OBJECTIVE: To assess the efficacy of a device using extraocular electrodes as a retinal prosthesis by evaluating the responses evoked in the visual cortex to electrical stimulation. METHODS: In anaesthetised cats, a lateral orbital dissection and ipsilateral parietal craniotomy was performed. Two extraocular retinal prosthesis (ERP) disc electrodes were sutured to the sclera on the lateral and superior aspects of the globe. Retinal stimulation was performed with charge-balanced constant-current pulses. Potentials evoked in the visual cortex were measured with a ball electrode placed on the lateral gyrus after removal of the dura. RESULTS: Stable attachment of the ERP electrodes to the globe was achieved with scleral sutures. Visual cortex responses were recorded with the electrodes in bipolar and monopolar configurations. The evoked response consisted of an early component with a peak around 8 ms, and a late component with a peak after 50 ms. Thresholds for evoking a response occurred at current intensities as low as 500 microA. Through extrapolation from evoked response amplitude data, thresholds as low as 300 microA were calculated. Cathodal monopolar stimulation demonstrated lower thresholds than anodal stimulation for evoking cortical responses. CONCLUSIONS: The ERP electrodes can be easily attached to the globe and are effective in electrically stimulating the retina, evoking responses in the primary visual cortex. Threshold charge-density was within safe limits for neural stimulation.


Subject(s)
Blindness/therapy , Electric Stimulation Therapy/instrumentation , Electric Stimulation Therapy/methods , Evoked Potentials, Visual/physiology , Prostheses and Implants/trends , Retina/physiology , Visual Cortex/physiology , Animals , Cats , Electrodes, Implanted/standards , Electrodes, Implanted/trends , Optic Nerve/physiology , Phosphenes/physiology , Prostheses and Implants/standards , Sclera/anatomy & histology , Sclera/physiology , Sclera/surgery , Sensory Thresholds/physiology , Treatment Outcome , Vision, Ocular/physiology , Visual Pathways/physiology , Visual Perception/physiology
14.
Neurol Res ; 26(1): 21-34, 2004 Jan.
Article in English | MEDLINE | ID: mdl-14977054

ABSTRACT

A number of prevalent eye diseases exist which may lead to partial or total blindness, and for which there are currently no cures or means by which to restore lost sight. Based on recent progress, it has become apparent that artificial prosthetic devices, which would use electrical stimulation of neurons in the visual pathway to elicit visual percepts, are likely to some day become a viable treatment for patients blinded by these diseases. A number of recent scientific reviews have summarized general functional electrical stimulation (FES) approaches related to the visual system, and many of the technical considerations regarding fabrication, biocompatibility, stimulation thresholds and electrotoxicity. This review will address a principal outstanding question in retinal prosthesis development: the design and implementation of a functional interface with the retina. A functional interface between electrodes and retinal neurons will be stable, biocompatible, and will convey useful information to the visual system. Several parameters related to both the artificial and biological aspects of the interface must be considered; this paper will emphasize electrode design. Additional issues central to the development of prosthesis interface design, including retinal physiology, eye diseases, and existing animal models of retinal degeneration, are also summarized.


Subject(s)
Blindness/therapy , Electric Stimulation Therapy/trends , Electrodes, Implanted/trends , Neurons/physiology , Prostheses and Implants/trends , Retina/surgery , Animals , Biocompatible Materials/standards , Blindness/pathology , Blindness/physiopathology , Electric Stimulation Therapy/instrumentation , Electric Stimulation Therapy/methods , Electrodes, Implanted/adverse effects , Electrodes, Implanted/standards , Eye Diseases/pathology , Eye Diseases/physiopathology , Eye Diseases/therapy , Humans , Prostheses and Implants/adverse effects , Prostheses and Implants/standards , Retina/cytology , Retina/physiology , Visual Pathways/cytology , Visual Pathways/physiology , Visual Pathways/surgery
15.
Neurol Res ; 24(5): 413-30, 2002 Jul.
Article in English | MEDLINE | ID: mdl-12117310

ABSTRACT

Electrical stimulation of peripheral nerves can be used to cause muscle contraction, to activate reflexes, and to modulate some functions of the central nervous system (neuromodulation). If applied to the spinal cord or nerves controlling the lower urinary tract, electrical stimulation can produce bladder or sphincter contraction, produce micturition, and can be applied as a medical treatment in cases of incontinence and urinary retention. This article first reviews the history of electrical stimulation applied for treatment of bladder dysfunction and then focuses on the implantable Finetech-Brindley stimulator to produce bladder emptying, and on external and implantable neuromodulation systems for treatment of incontinence. We conclude by summarizing some recent research efforts including: (a) combined sacral posterior and anterior sacral root stimulator implant (SPARSI), (b) selective stimulation of nerve fibers for selective detrusor activation by sacral ventral root stimulation, (c) microstimulation of the spinal cord, and (d) a newly proposed closed-loop bladder neuroprosthesis to treat incontinence caused by bladder overactivity.


Subject(s)
Electric Stimulation Therapy/methods , Electric Stimulation Therapy/trends , Electrodes, Implanted/trends , Urinary Bladder, Neurogenic/surgery , Urinary Bladder/innervation , Urinary Bladder/surgery , Animals , Electrodes, Implanted/standards , Humans , Hypogastric Plexus/physiopathology , Hypogastric Plexus/surgery , Neural Pathways/physiopathology , Neural Pathways/surgery , Prostheses and Implants/standards , Prostheses and Implants/trends , Spinal Nerve Roots/physiopathology , Spinal Nerve Roots/surgery , Urinary Bladder/physiopathology , Urinary Bladder, Neurogenic/pathology , Urinary Bladder, Neurogenic/physiopathology
16.
Neurol Res ; 24(2): 116-24, 2002 Mar.
Article in English | MEDLINE | ID: mdl-11877893

ABSTRACT

Persistent cognitive disabilities represent the most troublesome consequences of acquired brain injury. Although these problems are widely recognized, few neuroprosthetic efforts have focused on developing therapeutic strategies aimed at improving general cognitive functions such as sustained attention, intention, working memory or awareness. If possible, effective modulation of these neuropsychologic components might improve recovery of interactive behaviors. The emerging field of neuromodulation holds promise that technologies developed to treat other neurological disorders may be adapted to address the cognitive problems of patients suffering from acquired brain injuries. We here discuss initial efforts at neuromodulation in patients in the persistent vegetative state and aspects of recent studies of the underlying neurobiology of PVS and other severe brain injuries. Innovative strategies for open-loop and closed-loop neuromodulation of impaired cognitive function are outlined. We discuss the possibilities of linking neuromodulation techniques to underlying neuronal mechanisms underpinning cognitive rehabilitation maneuvers. Ethical considerations surrounding the development of these strategies are reviewed.


Subject(s)
Brain Injuries/complications , Cognition Disorders/physiopathology , Cognition Disorders/rehabilitation , Electric Stimulation Therapy/trends , Prostheses and Implants/trends , Recovery of Function/physiology , Arousal/physiology , Cognition Disorders/pathology , Electric Stimulation Therapy/methods , Humans , Intralaminar Thalamic Nuclei/physiopathology , Nerve Net/physiology , Prostheses and Implants/standards , Vestibular Nuclei/physiopathology
17.
Neurol Res ; 23(5): 472-81, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11474803

ABSTRACT

The paper describes the application of a neural network (ANN) for controlling a functional neuromuscular stimulation (FNS) system to facilitate patient-responsive ambulation by paralyzed patients with traumatic, thoracic-level spinal cord injuries. The particular ANN that is employed is a modified Adaptive-Resonance-Theory (ART-1) network. It serves as a controller in an FNS system (the Parastep system) that is presently in use by approximately 500 patients worldwide (but still without ANN control) and which was the first and only FNS system approved by FDA. The proposed neural network discriminates above-lesion upper-trunk electromyographic (EMG) time series to activate standing and walking functions under FNS and controls FNS stimuli levels using response-EMG signals. For this particular application, several modifications are introduced into the standard ART-1 ANN. First, a modified on-line learning rule is proposed. The new rule assures bi-directional modification of the stored patterns and prevents noise interference. Second, a new reset rule is proposed, which prevents 'exact matching' when the input is a subset of the chosen pattern. A single ART-1-based structure is being applied to solving two problems, namely (1) signal pattern recognition and limb function determination, and (2) control of stimulation levels. This also facilitates ambulation of paraplegics under FNS, with adequate patient interaction in initial system training, retraining the network when needed, and in allowing patient's manual over-ride in the case of error, where any manual over-ride serves as a re-training input to the neural network. The ANN control facilitates continuous update of control settings during normal use, without formal retraining.


Subject(s)
Electromyography/methods , Gait/physiology , Neural Networks, Computer , Paraplegia/rehabilitation , Prostheses and Implants/standards , Spinal Cord Injuries/rehabilitation , Transcutaneous Electric Nerve Stimulation/methods , Electromyography/instrumentation , Electronics, Medical/instrumentation , Electronics, Medical/methods , Feedback/physiology , Humans , Muscle Contraction/physiology , Paraplegia/physiopathology , Signal Processing, Computer-Assisted/instrumentation , Spinal Cord Injuries/physiopathology , Transcutaneous Electric Nerve Stimulation/instrumentation
18.
Biomaterials ; 17(7): 725-33, 1996 Apr.
Article in English | MEDLINE | ID: mdl-8672635

ABSTRACT

Neonatal rat calvarial osteoblasts were cultured on Ti-6Al-4V, Co-Cr-Mo alloy, 316L stainless steel and polystyrene (reference substrate) in the presence of ascorbic acid and 10 mM beta-glycerophosphate for 16, 17, 18, 19, 20, 21, 24 and 28 d. Scanning electron microscopy examination revealed that osteoblasts cultured on these orthopaedic/dental implant metals synthesized and deposited an extracellular matrix containing collagenous and non-collagenous components, as well as mineral nodules of various morphologies. Energy dispersive spectrometry revealed that the mineral deposits consisted of three distinct chemical compositions: calcium phosphate, calcium-sulphur-phosphorus, and calcium only. Backscattered electron imaging demonstrated that both the calcium phosphate and calcium-only deposits were electron dense, while the calcium-sulphur-phosphorus deposits were electron translucent. X-ray diffraction analysis indicated that the bulk of the osteoblast mineral deposits was amorphous hydroxyapatite; in addition, electron diffraction analysis revealed small regions of crystalline hydroxyapatite.


Subject(s)
Dental Implants/standards , Minerals/metabolism , Osteoblasts/metabolism , Prostheses and Implants/standards , Alloys , Animals , Calcium/metabolism , Calcium Phosphates/metabolism , Cells, Cultured , Chromium/metabolism , Cobalt/metabolism , Extracellular Matrix/metabolism , Hydroxyapatites/metabolism , Microscopy, Electron, Scanning , Molybdenum/metabolism , Osteoblasts/cytology , Phosphorus/metabolism , Rats , Stainless Steel/chemistry , Sulfur/metabolism , Titanium/metabolism , X-Ray Diffraction
19.
Biomaterials ; 17(1): 15-22, 1996 Jan.
Article in English | MEDLINE | ID: mdl-8962942

ABSTRACT

In the rabbit tibia, commercially pure titanium implants blasted with 25-microns Al2O3 and TiO2 particles respectively were inserted and studied with respect to removal torque and histomorphometry. In the rabbit femur, as-machined implants and implants blasted with 75-microns Al2O3 particles were histomorphometrically compared. Before implant insertion, the differently produced surface topographies were characterized numerically and visually. The tibial implants blasted with different materials and the same sized (25 microns) blasting particles demonstrated similar results. Comparing implants blasted with 75-microns Al2O3 particles to as-machined implants, the blasted specimens exhibited a statistically significant higher bone-to-metal contact after 12 weeks in the rabbit bone.


Subject(s)
Aluminum Oxide/chemistry , Bone Screws/standards , Prostheses and Implants/standards , Titanium , Animals , Biocompatible Materials , Femur/metabolism , Femur/surgery , Male , Particle Size , Rabbits , Surface Properties , Tibia/metabolism , Tibia/surgery , Titanium/chemistry , Titanium/metabolism
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