The following chapter on light therapy covers various procedures and treatment methods that address a variety of diseases through therapeutic application of different light variants. The historical traces of light therapy go back to ancient times. As early as the 2nd century BC, the Greek physician Herodotus recommended so-called heliotherapy (sun therapy) as a general treatment for physical ailments. Soon, in the 2nd century AD, depression was treated with sunlight. Technically, light therapy or phototherapy refers to the use of the optical spectrum emitted by the sun. This includes lower-energy thermal radiation (e.g., infrared light), visible light, and higher-energy ultraviolet radiation. In most cases, only artificial light sources are used for therapeutic treatment. Today, light therapy is used mainly in two major fields: In dermatology (the study of skin diseases), light is used therapeutically to treat various skin diseases (e.g. psoriasis – psoriasis). This form of light therapy is also called phototherapy. The second major area is light therapy for depressive disorders, but especially for seasonal depression (winter depression, SAD). In addition, there are a number of other applications. In the following, different subtypes of light therapy are presented. Each of them is treated separately in a complete text and described in detail.
The procedures
- Bright-Light Therapy – This form of therapy is used to treat depressive mood by intervening in the biorhythm of the organism, which is influenced, among other things, by the darkness or daylight.
- Blue light therapy – Blue light therapy is used primarily for the treatment of jaundice neonatorum (neonatal jaundice) and is a standard therapy here. In addition, this therapy can also be used in some dermatological diseases (skin diseases).
- Light therapy for winter depression – This form of therapy is formally similar to bright light therapy and is specifically designed for the treatment of winter depression, also known as seasonal affective disorder (SAD).
- Light therapy for psoriasis – Treatment of psoriasis is done with therapeutic UV light and is a very successful method. Broad-spectrum UVB, narrow-spectrum UVB and PUVA therapy (UVA light in combination with psoralen), also known as photochemotherapy, are used.
- Red Light Therapy/Ultrarred Light Therapy – These forms of light therapy achieve heat through red light or infrared light, which has great therapeutic benefits. For this reason, the procedures are also counted as part of the field of heat therapy.
- Soft laser treatment – Soft laser therapy is a gentle procedure that uses a low power density laser to effectively treat pain, tension and injury of various etiologies and a variety of other conditions.
- UVB 311 nm light therapy – This subspecialty of phototherapy effectively treats skin conditions (specifically psoriasis – dandruff) using a so-called UVB narrow spectrum lamp, which emits an ultraviolet light with a wavelength of exactly 311 nm. This method achieves better success than conventional UVB broad spectrum lamps under less erythema (formation of redness).
- UV light therapy – UV light is used, among other things, specifically for the treatment of vitamin D deficiency and its consequences.
The procedures, which are summarized under the term light therapy, represent extremely versatile applicable and very specialized therapy options in their respective fields. They allow the patient an individually designable treatment of his disease and can increase the well-being or restore health.