Transcorneal electrical stimulation

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Transcorneal electrical stimulation (TES) is a therapy developed for use in patients with a variety of eye diseases. The procedure involves placing electrodes in the form of contact lenses upon the patient's corneas, with a reference electrode on the skin near each eye. A weak current is delivered through the electrodes, with the intent of stimulating the visual system and enhancing its activity.

As of 2022, the technique was still in the early stages of research in human patients. A review of literature published in 2020 estimated this therapy as "probably effective" in the treatment of retinitis pigmentosa, based on the evidence available at the time. [1]

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Electroconvulsive therapy (ECT) is a psychiatric treatment where a generalized seizure is electrically induced to manage refractory mental disorders. Typically, 70 to 120 volts are applied externally to the patient's head, resulting in approximately 800 milliamperes of direct current passing between the electrodes, for a duration of 100 milliseconds to 6 seconds, either from temple to temple or from front to back of one side of the head. However, only about 1% of the electrical current crosses the bony skull into the brain because skull impedance is about 100 times higher than skin impedance.

<span class="mw-page-title-main">Deep brain stimulation</span> Neurosurgical treatment involving implantation of a brain pacemaker

Deep brain stimulation (DBS) is a neurosurgical procedure involving the placement of a medical device called a neurostimulator, which sends electrical impulses, through implanted electrodes, to specific targets in the brain for the treatment of movement disorders, including Parkinson's disease, essential tremor, dystonia, and other conditions such as obsessive-compulsive disorder (OCD) and epilepsy. While its underlying principles and mechanisms are not fully understood, DBS directly changes brain activity in a controlled manner.

<span class="mw-page-title-main">Cranial electrotherapy stimulation</span> Form of neurostimulation

Cranial electrotherapy stimulation (CES) is a form of neurostimulation that delivers a small, pulsed, alternating current via electrodes on the head. CES is used with the intention of treating a variety of conditions such as anxiety, depression and insomnia. CES has been suggested as a possible treatment for headaches, fibromyalgia, smoking cessation, and opiate withdrawal, but there is little evidence of effectiveness for many of these conditions and the evidence for use in acute depression is not sufficient to justify it.

<span class="mw-page-title-main">Transcutaneous electrical nerve stimulation</span> Therapeutic technique

Transcutaneous electrical nerve stimulation is the use of electric current produced by a device to stimulate the nerves for therapeutic purposes. TENS, by definition, covers the complete range of transcutaneously applied currents used for nerve excitation although the term is often used with a more restrictive intent, namely to describe the kind of pulses produced by portable stimulators used to reduce pain. The unit is usually connected to the skin using two or more electrodes which are typically conductive gel pads. A typical battery-operated TENS unit is able to modulate pulse width, frequency, and intensity. Generally, TENS is applied at high frequency (>50 Hz) with an intensity below motor contraction or low frequency (<10 Hz) with an intensity that produces motor contraction. More recently, many TENS units use a mixed frequency mode which alleviates tolerance to repeated use. Intensity of stimulation should be strong but comfortable with greater intensities, regardless of frequency, producing the greatest analgesia. While the use of TENS has proved effective in clinical studies, there is controversy over which conditions the device should be used to treat.

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<span class="mw-page-title-main">Electrical brain stimulation</span> Form of electrotherapy

Electrical brain stimulation (EBS), also referred to as focal brain stimulation (FBS), is a form of electrotherapy used as a technique in research and clinical neurobiology to stimulate a neuron or neural network in the brain through the direct or indirect excitation of its cell membrane by using an electric current. EBS is used for research or for therapeutic purposes.

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Neurostimulation is the purposeful modulation of the nervous system's activity using invasive or non-invasive means. Neurostimulation usually refers to the electromagnetic approaches to neuromodulation.

Neuromodulation is "the alteration of nerve activity through targeted delivery of a stimulus, such as electrical stimulation or chemical agents, to specific neurological sites in the body". It is carried out to normalize – or modulate – nervous tissue function. Neuromodulation is an evolving therapy that can involve a range of electromagnetic stimuli such as a magnetic field (rTMS), an electric current, or a drug instilled directly in the subdural space. Emerging applications involve targeted introduction of genes or gene regulators and light (optogenetics), and by 2014, these had been at minimum demonstrated in mammalian models, or first-in-human data had been acquired. The most clinical experience has been with electrical stimulation.

<span class="mw-page-title-main">Baroreflex activation therapy</span>

Baroreflex activation therapy is an approach to treating high blood pressure and the symptoms of heart failure. It uses an implanted device to electrically stimulate baroreceptors in the carotid sinus region. This elicits a reflex response through the sympathetic and vagal nervous systems that reduces blood pressure.

References

  1. Perin C, Viganò B, Piscitelli D, Matteo BM, Meroni R, Cerri CG (2020). "Non-invasive current stimulation in vision recovery: a review of the literature". Restorative Neurology and Neuroscience. 38 (3): 239–250. doi:10.3233/RNN-190948. PMC   7504999 . PMID   31884495.