TENS equipment, techniques, and biophysical principles

2014 ◽  
Keyword(s):  
Clinical Practice ◽  
Peripheral Nerve ◽  
Nerve Fibre ◽  
Electrical Current ◽  
Electrical Characteristics ◽  
Nerve Fibres ◽  
Electrical Currents ◽  
Nerve Impulses ◽  
Different Types ◽  
Nociceptive Information

The purpose of the electrical current delivered during TENS is to generate nerve impulses in peripheral nerve fibres to modulate the flow of nociceptive information and reduce pain. The characteristics of the electrical currents (i.e. stimulating parameters) and physiology at the electrode–skin interface will influence which nerve fibres are excited. Conventional TENS and acupuncture-like TENS are two techniques developed to stimulate different types of nerve fibres. The purpose of this chapter is to overview the biophysical principles of TENS and to explain how these principles have been used to inform clinical practice by covering TENS equipment and the standard TENS device, the electrical characteristics of currents produced by a standard TENS device, lead wires and electrodes, the physiology at the electrode–skin interface including nerve fibre activation by TENS, and TENS techniques used in clinical practice, including conventional TENS and acupuncture-like TENS (AL-TENS).

Paths taken by sensory nerve fibres in aneural chick wing buds

Development ◽  
1985 ◽  
Vol 86 (1) ◽  
pp. 109-124
Author(s):  
Gavin J. Swanson
Keyword(s):  
Peripheral Nerve ◽  
Nerve Fibre ◽  
Sensory Nerve ◽  
Axon Outgrowth ◽  
Sensory Ganglia ◽  
Chick Embryos ◽  
Nerve Fibres ◽  
Embryo Chick ◽  
Wing Bud ◽  
Host Embryo

What constrains growing nerves to follow the paths they take during the development of peripheral nerve patterns? This paper examines two, related, topics concerning the pathways taken by sensory nerve fibres in the embryo chick wing: the constraints imposed on the nerves by limb tissues; and the timing of axon outgrowth. Sensory ganglia from 7-day-old chick embryos were grafted into younger host embryo wing buds which had been previously denervated. The resultant nerve patterns revealed that, first, nerve fibres could grow almost anywhere within the wing bud, with the exceptions of cartilage and a region just beneath the growing tip. Secondly, the younger the host wing bud at the time of grafting, the more likely the neurites were to form a thick fascicle which followed the limb's normal nerve pathways. The wing apparently does not impose a rigid restraint on nerves to grow only along certain routes; however, if a nerve fibre reaches a normal nerve pathway, it prefers to follow it.

Nerve Stimulators Used for Peripheral Nerve Blocks Vary in Their Electrical Characteristics

2003 ◽  
Vol 98 (4) ◽  
pp. 969-974 ◽  
Author(s):  
Admir Hadzic ◽  
Jerry Vloka ◽  
Nihad Hadzic ◽  
Daniel M. Thys ◽  
Alan C. Santos
Keyword(s):  
Peripheral Nerve ◽  
Electrical Current ◽  
The United States ◽  
Electrical Characteristics ◽  
Nerve Blocks ◽  
Current Output ◽  
Voltage Output ◽  
Median Error ◽  
Peripheral Nerve Blockade ◽  
Maximum Voltage

Background Nerve stimulation with a low-intensity electrical current has become a vital part of the performance of peripheral nerve blockade. The purpose of this study was to compare the accuracy and characteristics of peripheral nerve stimulators used in clinical practice in the United States. Methods Fifteen peripheral nerve stimulators were fitted with fresh batteries and set to deliver currents ranging from 0.1 to 4.0 mA into a series of high-tolerance resistance loads ranging from 1 to 100 komega. The current output, stimulus duration, morphology, frequency, and maximum voltage output were studied using a factory-calibrated oscilloscope. Results All peripheral nerve stimulators performed uniformly well when set to deliver currents of 1.0 mA or more into a standard resistance load of 1 or 2 komega. However, at lower currents, the median error (%) increased from 2.4 (-5-144%) at 0.5 mA to 10.4 (-24-180%) at 0.1 mA into a 1 komega load. The morphology of the stimulus was characterized by a regular monophasic square pulse at current outputs of up to 1 mA and at a resistance of 1 komega. The stimulus waveform became particularly distorted as the impedance load was increased. The duration of the default stimulus set by the manufacturer varied from 34.8 to 460 micros among the peripheral nerve stimulators tested. The maximum voltage output ranged from 7.4 to 336 Volts. Conclusions Nerve stimulators used for regional anesthesia vary greatly in accuracy of current output and in manufacturer-selected electrical characteristics (e.g., current duration, stimulating frequency, maximum voltage output).

“Bridging Gaps – Improving Outcomes”: Problem domains in schizophrenia research, treatment and policy

2016 ◽  
Vol 13 (03) ◽  
pp. 118-120
Author(s):  
W. Wölwer ◽  
W. Gaebel ◽  
V. Toeller
Keyword(s):  
Clinical Practice ◽  
Mental Healthcare ◽  
Knowledge Gaps ◽  
Everyday Clinical Practice ◽  
Treatment Gaps ◽  
Different Types

Summary Background: The provision of mental healthcare for patients with schizophrenia is still characterized both by knowledge gaps and by treatment gaps in everyday clinical practice. Aim: This article discusses the different types of treatment gaps in schizophrenia and describes actions taken to overcome these gaps especially in Europe.

METHODS FOR SIMULATION OF ACUTE BRAIN ISCHEMIA: PATHOPHYSIOLOGICAL SUBSTANTIATION OF SELECTION AND IMPORTANCE FOR CLINICAL PRACTICE

2019 ◽  
pp. 142-152
Author(s):  
Б.И. Гельцер ◽  
Э.В. Слабенко ◽  
Ю.В. Заяц ◽  
В.Н. Котельников
Keyword(s):  
Clinical Practice ◽  
Experimental Studies ◽  
Cerebrovascular Diseases ◽  
Experimental Models ◽  
Pathological Process ◽  
Ischemic Brain ◽  
Actual Clinical Practice ◽  
Acute Cerebral Ischemia ◽  
Different Types ◽  
Acute Brain Ischemia

Одним из основных требований к разработке экспериментальных моделей цереброваскулярных заболеваний является их максимальная приближенность к реальной клинической практике. В работе систематизированы данные по основным методам моделирования острой ишемии головного мозга (ОИГМ), представлена их классификация, анализируются данные о преимуществах и недостатках той или иной модели. Обсуждаются результаты экспериментальных исследований по изучению патогенеза ОИГМ с использованием различных моделей (полной и неполной глобальной, локальной и мультифокальной ишемии) и способов их реализации (перевязка артерий, клипирование, коагуляция, эмболизация и др.). Особое внимание уделяется «стабильности» последствий острого нарушения мозгового кровообращения: необратимых ишемических повреждений головного мозга или обратимых с реперфузией заданной продолжительности. Отмечается, что важное значение в этих исследованиях должно принадлежать современным методам прижизненной визуализации очагов острого ишемического повреждения, что позволяет оценивать динамику патологического процесса. Предлагаемый метод отвечает требованиям гуманного обращения с животными. Подчеркивается, что выбор релевантной модели ОИГМ определяется задачами предстоящего исследования и технологическими ресурсами научной лаборатории. Development of experimental models for acute forms of cerebrovascular diseases is essential for implementation of methods for their prevention and treatment. One of the principal requirements to such models is their maximum approximation to actual clinical practice. This review systematized major models of acute cerebral ischemia (ACI), their classification, and presented information about their advantages and shortcomings. Also, the review presented results of experimental studies on pathophysiological mechanisms of different types of modeled ACI (complete and incomplete global, local, and multifocal ischemia) and methods for creating these models (arterial ligation, clipping, coagulation, embolization, etc.). Particular attention was paid to “stability” of the consequences of acutely impaired cerebral circulation - an irreversible ischemic brain injury or a reversible injury with reperfusion of a given duration. The authors emphasized that in such studies, a special significance should be given to intravital imaging of acute ischemic damage foci using modern methods, which allow assessing the dynamics of the pathological process and meet the requirements to humane treatment of animals. The choice of a relevant ACI model is determined by objectives of the planned study and the technological resources available at the research laboratory.

The CSF p-tau181/Aβ42 Ratio Offers a Good Accuracy “In Vivo” in the Differential Diagnosis of Alzheimer’s Dementia

2019 ◽  
Vol 16 (7) ◽  
pp. 587-595 ◽  
Author(s):  
Roberto Santangelo ◽  
Alessandro Dell'Edera ◽  
Arianna Sala ◽  
Giordano Cecchetti ◽  
Federico Masserini ◽  
...  
Keyword(s):  
Clinical Practice ◽  
Clinical Diagnosis ◽  
Fdg Pet ◽  
Amyloid Β ◽  
Cost Effective ◽  
Daily Clinical Practice ◽  
Different Types ◽  
Experimental Trials ◽  
Csf Findings

Background: The incoming disease-modifying therapies against Alzheimer’s disease (AD) require reliable diagnostic markers to correctly enroll patients all over the world. CSF AD biomarkers, namely amyloid-β 42 (Aβ42), total tau (t-tau), and tau phosphorylated at threonine 181 (p-tau181), showed good diagnostic accuracy in detecting AD pathology, but their real usefulness in daily clinical practice is still a matter of debate. Therefore, further validation in complex clinical settings, that is patients with different types of dementia, is needed to uphold their future worldwide adoption. Methods: We measured CSF AD biomarkers’ concentrations in a sample of 526 patients with a clinical diagnosis of dementia (277 with AD and 249 with Other Type of Dementia, OTD). Brain FDG-PET was also considered in a subsample of 54 patients with a mismatch between the clinical diagnosis and the CSF findings. Results: A p-tau181/Aβ42 ratio higher than 0.13 showed the best diagnostic performance in differentiating AD from OTD (86% accuracy index, 74% sensitivity, 81% specificity). In cases with a mismatch between clinical diagnosis and CSF findings, brain FDG-PET partially agreed with the p-tau181/Aβ42 ratio, thus determining an increase in CSF accuracy. Conclusions: The p-tau181/Aβ42 ratio alone might reliably detect AD pathology in heterogeneous samples of patients suffering from different types of dementia. It might constitute a simple, cost-effective and reproducible in vivo proxy of AD suitable to be adopted worldwide not only in daily clinical practice but also in future experimental trials, to avoid the enrolment of misdiagnosed AD patients.

scholarly journals Early Detection of Diabetic Peripheral Neuropathy: A Focus on Small Nerve Fibres

Diagnostics ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 165
Author(s):  
Jamie Burgess ◽  
Bernhard Frank ◽  
Andrew Marshall ◽  
Rashaad S. Khalil ◽  
Georgios Ponirakis ◽  
...  
Keyword(s):  
Peripheral Neuropathy ◽  
Nerve Fibre ◽  
Diabetic Peripheral Neuropathy ◽  
Point Of Care ◽  
Unmet Need ◽  
Screening Tools ◽  
Nerve Fibres ◽  
Diagnostic Laboratory ◽  
Corneal Confocal Microscopy ◽  
Small Nerve

Diabetic peripheral neuropathy (DPN) is the most common complication of both type 1 and 2 diabetes. As a result, neuropathic pain, diabetic foot ulcers and lower-limb amputations impact drastically on quality of life, contributing to the individual, societal, financial and healthcare burden of diabetes. DPN is diagnosed at a late, often pre-ulcerative stage due to a lack of early systematic screening and the endorsement of monofilament testing which identifies advanced neuropathy only. Compared to the success of the diabetic eye and kidney screening programmes there is clearly an unmet need for an objective reliable biomarker for the detection of early DPN. This article critically appraises research and clinical methods for the diagnosis or screening of early DPN. In brief, functional measures are subjective and are difficult to implement due to technical complexity. Moreover, skin biopsy is invasive, expensive and lacks diagnostic laboratory capacity. Indeed, point-of-care nerve conduction tests are convenient and easy to implement however questions are raised regarding their suitability for use in screening due to the lack of small nerve fibre evaluation. Corneal confocal microscopy (CCM) is a rapid, non-invasive, and reproducible technique to quantify small nerve fibre damage and repair which can be conducted alongside retinopathy screening. CCM identifies early sub-clinical DPN, predicts the development and allows staging of DPN severity. Automated quantification of CCM with AI has enabled enhanced unbiased quantification of small nerve fibres and potentially early diagnosis of DPN. Improved screening tools will prevent and reduce the burden of foot ulceration and amputations with the primary aim of reducing the prevalence of this common microvascular complication.

scholarly journals Experimental Methods to Simulate and Evaluate Postsurgical Peripheral Nerve Scarring

2021 ◽  
Vol 10 (8) ◽  
pp. 1613
Author(s):  
Alessandro Crosio ◽  
Giulia Ronchi ◽  
Benedetta Elena Fornasari ◽  
Simonetta Odella ◽  
Stefania Raimondo ◽  
...  
Keyword(s):  
Peripheral Nerve ◽  
Peripheral Nerves ◽  
Experimental Methods ◽  
Scar Tissue ◽  
Experimental Models ◽  
Tissue Formation ◽  
Surgical Interventions ◽  
Pubmed Database ◽  
Different Types ◽  
Scar Tissue Formation

As a consequence of trauma or surgical interventions on peripheral nerves, scar tissue can form, interfering with the capacity of the nerve to regenerate properly. Scar tissue may also lead to traction neuropathies, with functional dysfunction and pain for the patient. The search for effective antiadhesion products to prevent scar tissue formation has, therefore, become an important clinical challenge. In this review, we perform extensive research on the PubMed database, retrieving experimental papers on the prevention of peripheral nerve scarring. Different parameters have been considered and discussed, including the animal and nerve models used and the experimental methods employed to simulate and evaluate scar formation. An overview of the different types of antiadhesion devices and strategies investigated in experimental models is also provided. To successfully evaluate the efficacy of new antiscarring agents, it is necessary to have reliable animal models mimicking the complications of peripheral nerve scarring and also standard and quantitative parameters to evaluate perineural scars. So far, there are no standardized methods used in experimental research, and it is, therefore, difficult to compare the results of the different antiadhesion devices.

scholarly journals ID Learning Unit: Understanding and Interpreting Testing for Clostridium difficile

2014 ◽  
Vol 1 (1) ◽  
Author(s):  
Daniel A. Solomon ◽  
Danny A. Milner
Keyword(s):  
Clinical Practice ◽  
Clostridium Difficile ◽  
Basic Principles ◽  
Multiple Tests ◽  
Molecular Tests ◽  
Different Types

Abstract Understanding and interpreting the molecular tests for Clostridium difficile is challenging because there are several different types of assays and most laboratories combine multiple tests in order to assess for presence of disease. This learning unit demonstrates the basic principles of each test along with its strengths and weaknesses, and illustrates how the tests are used in clinical practice.

scholarly journals The ectopic newly-formed nerve fibres which repopulate the long-time denervated and atrophic chick skeletal muscle

1968 ◽  
Vol 26 (3) ◽  
pp. 187-194 ◽  
Author(s):  
Eros Abrantes Erhart ◽  
Cecil José Rezze ◽  
Walter Biazotto
Keyword(s):  
Skeletal Muscle ◽  
Electrical Stimulation ◽  
Nerve Fibre ◽  
Nerve Trunk ◽  
Direct Electrical Stimulation ◽  
Nerve Fibres ◽  
Motor Endplates ◽  
Proximal Stump ◽  
Long Time ◽  
Contralateral Muscle

1. The whole biventer cervicis muscles of the chick, being innervated by a branch of the dorsal ramus of C, presents structural Deculiarities which recommend it as good skeletal muscle for embryological, anatomical, physiological and pharmacological neuro-muscular investigations. 2. The nerve trunk responsible for the innervation of the distal belly runs completely included within the intermediate tendon; therefore, a tendon transection determines complete denervation and nerve fibre degeneration of the distal belly of the muscle. 3. Long-time experimentally denervated distal bellies (from three up to twelve months) are repopulated by ectopic nerve fibres which must have arisen from a source other than the proximal stump, neighbour nerves or nervi-vasorum. 4. Motor endplates appear in these long-time (eight or more months) denervated biventer cervicis distal bellies. 5. Although atrophic-looking such muscle bellies responded to indirect and to direct electrical stimulation — 1.5 V — by contraction. 6. The long-time denervated distal bellies of the biventer cervicis muscle of the chick, when properly reoperated by cross-grafting suture with the normal contralateral muscle, lost their atrophic appearance and showed to be successfully recovered in about thirty days.

scholarly journals Honey dressing on a leg ulcer with tendon exposure in a patient with type 2 diabetes

2018 ◽  
Vol 2018 ◽  
Author(s):  
Ilaria Teobaldi ◽  
Vincenzo Stoico ◽  
Fabrizia Perrone ◽  
Massimiliano Bruti ◽  
Enzo Bonora ◽  
...  
Keyword(s):  
Type 2 Diabetes ◽  
Clinical Practice ◽  
Wound Dressing ◽  
Biological Properties ◽  
Healing Time ◽  
Foot Ulcers ◽  
Diabetic Foot Ulcers ◽  
Scientific Interest ◽  
Different Types

Summary Honey has been used as a wound dressing for hundreds of years by ancient civilizations, but only recently it has acquired scientific interest because of its relevant biological properties. In the last decade, indeed, several trials and observational studies have reported that, compared to conventional treatment (e.g. antiseptics, polyurethane film, paraffin gauze, soframycin-impregnated gauze), honey dressings seem to be better in healing time of different types of wounds, including diabetic foot ulcers. However, to date, information about a potential favorable biological effect of honey dressings on diabetic ulcers with exposed tendon are still scarce. Notably, foot or leg ulcers with exposed tendon are serious complications in patients with type 2 diabetes, as they are associated with an increased risk of adverse outcome. Therefore, the use of effective and safe treatments to bring these lesions to timely healing is very important in clinical practice. We herein report the case of a Caucasian adult patient with type 2 diabetes presenting a chronic right posterior lower limb ulcer (Texas University Classification (TUC) 2D) with tendon exposure that was successfully treated with honey dressings (glucose oxidase (GOX) positive with peroxide activity) in addition to systemic antibiotic therapy, surgical toilette and skin graft. In our case, the use of honey dressing for treating exposed tendon tissue probably allowed the timely wound healing. Although further studies are required, such treatment may constitute part of the comprehensive management of diabetic wounds, including those with tendon exposure, and should be considered by clinicians in clinical practice. Learning points: Honey has been used as a wound dressing for hundreds of years, but only recently it has acquired scientific interest for its biological properties. Several studies have documented that, compared to conventional dressings, honey seems to be better in healing time of different types of wounds, including diabetic foot ulcers. Our case report is the first to highlight the importance to use honey dressings also for the treatment of ulcers with tendon exposure in patients with type 2 diabetes, suggesting that this kind of dressing should be considered by clinicians in clinical practice.

Sign in / Sign up

Export Citation Format

Share Document