Light therapy (phototherapy)
Last reviewed: 23.04.2024
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Light therapy (phototherapy) is a method of local or general exposure to incoherent unpolarized electromagnetic radiation of the optical spectrum of the relevant parameters, including the infrared, visible and ultraviolet parts of this spectrum, which is carried out by means of a radiator located above the definitions of the patient's naked body at a distance of 10-100 cm.
Advantages of phototherapy - the practical absence of contraindications and side effects, methodical simplicity, the possibility of combining with pharmacological drugs.
Phototherapy is used to treat patients with various neurological and psychiatric diseases (depression, seasonal affective disorders, insomnia, premenstrual syndrome, parkinsonism, focal dystonic hyperkinesis, psycho-vegetative syndrome, tension headaches) and to enhance the adaptation of healthy people to night work and to flights a few time zones. In some cases, phototherapy is more effective than medicinal and other therapies.
The features of the action of the incoherent unpolarized electromagnetic radiation of the optical spectrum are related to:
- with resonant phenomena of various biological structures and radiation of a certain wavelength,
- with the energy capacity of the photons of the corresponding parts of this spectrum,
- with an APC of radiation of a particular wavelength.
Phototherapy with the optical spectrum of EMR used in physiotherapy is represented by an ultraviolet part with a wavelength of 180 to 400 nm, a visible part with a wavelength of 400 to 760 nm and an infrared part with a wavelength of 760 nm to 10 μm.
The interaction of electromagnetic radiation of the optical spectrum of different wavelengths with respect to the resonance mechanism is associated with the absorption of this radiation by the corresponding biosubstrates. The pattern is determined by the size and complexity of the structure of the biosubstratum. So, the spectrum of EMP absorption by amino acids is in the ultraviolet part, the larger molecules absorb the EMR of the visible part, in DNA the absorption maximum is in the red and near infrared part of the EMR optical spectrum.
The photon energy of the EMR of the ultraviolet part of the spectrum is 300 kJ / mol and more, the visible part is from 120 to 300 kJ / mol, the infrared part is 120 kJ / mol and less. Due to the high photon energy of the ultraviolet and the visible part of the optical spectrum close to it, the chemical bonds (strong interactions that determine the chain structure of biopolymers) break down, and the destruction of macromolecules, primarily the protein. Photons with a lower power capacity initiate various electrodynamic changes with subsequent conformational rearrangements of biological substrates.
The EPM of the optical spectrum during phototherapy is usually not indicated, since the APM is associated with a certain wavelength (spectral density of radiation). However, the total APM of the ultraviolet part of the optical spectrum is in the range 0.1-10 mW / cm2. In the visible and infrared part, the total APM reaches several W / cm2 with an apparent predominance even in the visible part (70-80%) of the spectral density of infrared radiation, and due to this, the predominance of the thermal effect and the increase in the temperature of the irradiated skin is explained. Main clinical effects:
- at ultraviolet irradiation - pigment-forming, immunostimulating, photosensitizing! Bactericidal and bacteriostatic;
- when exposed to the visible part of the spectrum - vasoactive local analgesic, metabolic, anti-inflammatory;
- with infrared radiation - anti-inflammatory (decongestant), regenerative-proliferative, local anesthetic, vasoactive, metabolic.
[The equipment used by phototherapy (phototherapy)
- generators of ultraviolet radiation: ORK-21M (mercury quartz irradiator on a tripod), OKN-11M1 (ultraviolet tabletop irradiator), BOD-91 (bactericidal irradiator on a tripod), EOD-101 (erythemal irradiator on a tripod), "ОН-7" and "ОН-82я (irradiators for the nasopharynx)," BOP-4 "(bactericidal irradiator portable), etc .;
- generators of visible radiation: household incandescent lamps, "VOD-11" (stationary irradiator on a tripod), etc .;
- generators of infrared radiation: "LSS-6M" ("Sollux" stationary lamp), "LIK-5M" (reflector with infra-red table lamp), "LSN-1M (table lamp" Sollux "), Minin lamp (electric medical reflector) and etc.
Phototherapy is carried out with bio-lamps of a certain power. Daily exposure is 30-60 minutes. Spend in the morning hours for at least 10 days. The minimum illumination, which gives a therapeutic effect, is 2500 lux. Biolamp special design recreates the solar spectrum without ultraviolet rays. Biolamp makes it possible to carry out treatment both in a hospital and outpatient settings (including at home), it can be used in any room.