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the therapeutic use of sunlight or optical radiation, including infrared, visible, and ultraviolet radiation; a branch of physical therapy. Luminous energy’s effect on man is determined by its intensity (strength of the source and distance to the irradiated surface), by the duration of irradiation, and by the penetration depth of electromagnetic waves. The penetration depth, which depends on the light-wave length, is greatest with infrared and visible rays and least with ultraviolet rays. Erythema, that is, redness of the skin, may appear a few minutes after irradiation, for example, by infrared rays, or two to eight hours after exposure to ultraviolet rays. The intensity of the skin reaction varies with such factors as age, the time of year and the sensitivity of the skin in different parts of the body to different kinds of rays. It can change with some pathological conditions and after the ingestion of certain medicinal substances. The irradiated area acquires a tan in three to four days.

Thermal and luminescent artificial light sources are used in phototherapy. Thermal sources include incandescent lamps that emit infrared and visible rays, general and local light baths, Minin lights, and infrared rays. The quantity and composition of the energy released by these sources depend on the temperature of the radiating body. Luminescent sources, in which radiation is achieved by electrical, chemical, and other processes, include mercury-vapor lamps, luminescent erythematous lamps, and arc bactericidal lamps.

Ultraviolet irradiation, both local and general, is used to compensate for an ultraviolet-radiation insufficiency and to increase resistance to various infections, for example, influenza. It is used as an analgesic and antiphlogistic in treating diseases of the joints, the peripheral nervous system (neuritis, neuralgia, radiculitis), the muscular system (myositis), and the respiratory system (bronchitis, pleurisy), as well as in treating skin diseases, gynecologic and metabolic disorders, and some forms of tuberculosis. Ultraviolet irradiation is used in pediatrics in preventing rickets and acute respiratory diseases, in increasing the body’s defensive mechanisms against rheumatic fever between attacks, and, together with antirheumatics, in treating rheumatic fever during its acute phase. Thermal procedures and visible and infrared rays are used as analgesics and resorption agents primarily in treating subacute and chronic inflammatory diseases, neuralgia, and muscular pains.

Phototherapy is contraindicated in treating the active form of tuberculosis, neoplasms, pronounced heart failure, the second and third stages of hypertension, acute exhaustion, increased thyroid function, renal disease and insufficiency, and photopathy (a diseased condition caused by light).


References in periodicals archive ?
The double-blind, sham controlled, randomized and multi-centered study will test Theradome LH80 PRO's ability to promote hair growth in men when compared to what is known as a "Sham Device," a fake Laser Phototherapy unit worn by a control group unaware of the helmet's authenticity.
Unfortunately, studies that relate the Bf concentration to outcome in premature infants are complicated both by the widespread prophylactic use of phototherapy and by the high incidence of unrelated neurodevelopmental difficulties that attend the extrauterine existence of the premature neonate of very low birth weight.
Aziz Koleilat, general manager at GE Healthcare, Middle East, said: "The Lullaby LED phototherapy system is a great addition to our Lullaby performance product portfolio and offers a safe, efficient and cost effective solution to address one of the most common ailments in newborns.
Dogra S, De D: Phototherapy and photochemotherapy in childhood dermatoses.
Most dermatologists believe that home phototherapy is inferior to hospital treatment and that it carries more risks, despite there being no evidence to support this.
Phototherapy helps to reduce the bilirubin level and the risk of brain damage that can occur when bilirubin crosses from the blood into the brain, but it is unclear whether aggressive phototherapy to prevent the neurotoxic effects of bilirubin benefits or harms infants with extremely low birth weight (1000g or less).
They've assured me that they'll help you find a doctor as close to you as possible who is skilled in using phototherapy for skin conditions.
Lichen sclerosus therapeutics * Corticosteroids (topical, intralesional) (7) * Topical calcineurin antagonists (8) * Phototherapy (9, 10) Psoralen + ultraviolet A light Ultraviolet A1 light * Oral calcitriol (11)
The committee's metaanalysis also concluded that dawn simulation is effective in seasonal affective disorder (SAD), but that phototherapy with bright lights is not beneficial as an adjunctive treatment in non-SAD depression.
Phototherapy reduces these levels, but daily sessions-- often approaching 14 to 16 hours each--are necessary.
A fiberoptic pad that delivers light to a newborn's skin may offer simpler treatment for neonatal jaundice than the phototherapy currently used.
based Oregon Aesthetic Technologies (OAT) today announced the availability of ANSR: Acne Care, a next-generation acne treatment featuring clinically proven phototherapy and a powerful set of topical ingredients to fight acne and heal the skin.