Photomedicine is an interdisciplinary branch of

medicine Medicine is the science and Praxis (process), practice of caring for patients, managing the Medical diagnosis, diagnosis, prognosis, Preventive medicine, prevention, therapy, treatment, Palliative care, palliation of their injury or disease, ...

that involves the study and application of light with respect to health and disease. Photomedicine may be related to the practice of various fields of medicine including dermatology, surgery, interventional radiology, optical diagnostics, cardiology,

circadian rhythm sleep disorder Circadian rhythm sleep disorders (CRSD), also known as circadian rhythm sleep–wake disorders (CRSWD), are a family of sleep disorders that affect the timing of sleep. CRSDs cause a persistent pattern of sleep/wake disturbances that arise eit ...

s and oncology. A branch of photomedicine is

light therapy Light therapy, also called phototherapy or bright light therapy is the exposure to direct sunlight or artificial light at controlled wavelengths in order to treat a variety of medical disorders, including seasonal affective disorder (SAD), circ ...

in which bright light strikes the

retina The retina (; or retinas) is the innermost, photosensitivity, light-sensitive layer of tissue (biology), tissue of the eye of most vertebrates and some Mollusca, molluscs. The optics of the eye create a focus (optics), focused two-dimensional ...

e of the eyes, used to treat

circadian rhythm A circadian rhythm (), or circadian cycle, is a natural oscillation that repeats roughly every 24 hours. Circadian rhythms can refer to any process that originates within an organism (i.e., Endogeny (biology), endogenous) and responds to the env ...

disorders and

seasonal affective disorder Seasonal affective disorder (SAD) is a mood disorder subset in which people who typically have normal mental health throughout most of the year exhibit depressive symptoms at the same time each year. It is commonly, but not always, associated w ...

(SAD). The light can be sunlight or from a light box emitting white or blue (blue/green) light.

Examples

Photomedicine is used as a treatment for many different conditions: *

PUVA PUVA (psoralen and UVA) is an ultraviolet light therapy treatment for skin diseases: vitiligo, eczema, psoriasis, graft-versus-host disease, mycosis fungoides, large plaque parapsoriasis, and cutaneous T-cell lymphoma, using the sensitizing e ...

for the treatment of

psoriasis Psoriasis is a long-lasting, noncontagious autoimmune disease characterized by patches of abnormal skin. These areas are red, pink, or purple, dry, itchy, and scaly. Psoriasis varies in severity from small localized patches to complete b ...

Photodynamic therapy Photodynamic therapy (PDT) is a form of phototherapy involving light and a photosensitizing chemical substance used in conjunction with molecular oxygen to elicit cell death ( phototoxicity). PDT is used in treating acne, wet age-related macula ...

(PDT) for treatment of cancer and macular degeneration - Nontoxic light-sensitive compounds are targeted to malignant or other diseased cells, then exposed selectively to light, whereupon they become toxic and destroy these cells

phototoxicity Phototoxicity, also called photoirritation, is a chemically induced skin irritation, requiring light, that does not involve the immune system. It is a type of photosensitivity. The skin response resembles an exaggerated sunburn. The involved chem ...

. One

dermatological Dermatology is the branch of medicine dealing with the skin.''Random House Webster's Unabridged Dictionary.'' Random House, Inc. 2001. Page 537. . It is a speciality with both medical and surgical aspects. A dermatologist is a specialist medic ...

example of PDT is the targeting malignant cells by bonding the light-sensitive compounds to antibodies to these cells; light exposure at particular wavelengths mediates release of free radicals or other photosensitizing agents, destroying the targeted cells. * Treating circadian rhythm disorders *

Alopecia Hair loss, also known as alopecia or baldness, refers to a loss of hair from part of the head or body. Typically at least the head is involved. The severity of hair loss can vary from a small area to the entire body. Inflammation or scarring ...

pattern hair loss Pattern hair loss (also known as androgenetic alopecia (AGA)) is a hair loss condition that primarily affects the top and front of the scalp. In male-pattern hair loss (MPHL), the hair loss typically presents itself as either a receding front h ...

, etc. *

Free electron laser A free-electron laser (FEL) is a fourth generation light source producing extremely brilliant and short pulses of radiation. An FEL functions much as a laser but employs relativistic electrons as a gain medium instead of using stimulated emission ...

Laser hair removal Laser hair removal is the process of hair removal by means of exposure to pulses of laser light that destroy the hair follicle. It had been performed experimentally for about twenty years before becoming commercially available in 1995–1996. One ...

* IPL *

Photobiomodulation Low-level laser therapy (LLLT), cold laser therapy or photobiomodulation (PBM) is a medical treatment approach that applies low-level (low- power) lasers or light-emitting diodes (LEDs) to the surface of the body. Whereas high-power lasers are ...

* Optical diagnostics, for example

optical coherence tomography Optical coherence tomography (OCT) is a high-resolution imaging technique with most of its applications in medicine and biology. OCT uses coherent near-infrared light to obtain micrometer-level depth resolved images of biological tissue or oth ...

of coronary plaques using infrared light *

Confocal microscopy Confocal microscopy, most frequently confocal laser scanning microscopy (CLSM) or laser scanning confocal microscopy (LSCM), is an optical imaging technique for increasing optical resolution and contrast (vision), contrast of a micrograph by me ...

and

fluorescence microscopy A fluorescence microscope is an optical microscope that uses fluorescence instead of, or in addition to, scattering, reflection, and attenuation or absorption, to study the properties of organic or inorganic substances. A fluorescence micro ...

of ''

in vivo Studies that are ''in vivo'' (Latin for "within the living"; often not italicized in English) are those in which the effects of various biological entities are tested on whole, living organisms or cells, usually animals, including humans, an ...

'' tissue * Diffuse reflectance infrared fourier transform for ''in vivo'' quantification of

pigments A pigment is a powder used to add or alter color or change visual appearance. Pigments are completely or nearly solubility, insoluble and reactivity (chemistry), chemically unreactive in water or another medium; in contrast, dyes are colored sub ...

(normal and cancerous), and

hemoglobin Hemoglobin (haemoglobin, Hb or Hgb) is a protein containing iron that facilitates the transportation of oxygen in red blood cells. Almost all vertebrates contain hemoglobin, with the sole exception of the fish family Channichthyidae. Hemoglobin ...

* Perpendicular- polarized

flash photography A flash is a device used in photography that produces a brief burst of light (lasting around of a second) at a color temperature of about 5500 Kelvin, K to help illuminate a scene. The main purpose of a flash is to illuminate a dark scene. Ot ...

and

fluorescence Fluorescence is one of two kinds of photoluminescence, the emission of light by a substance that has absorbed light or other electromagnetic radiation. When exposed to ultraviolet radiation, many substances will glow (fluoresce) with colore ...

photography of the skin

References

External links

Medical physics Laser medicine Light therapy {{treatment-stub

Examples

See also

References

Further reading

External links