Instruct: Given a question, retrieve relevant passages that answer the question.
Query: How is infrared light used in therapy?
"Infrared therapy" uses infrared heaters to emit infrared light experienced as radiant heat which is absorbed by the surface of the skin. Saunas heat the body primarily by conduction and convection from the heated air and by radiation of the heated surfaces in the sauna room. Because of this, infrared therapy is not considered a sauna by Finnish sauna societies. Nevertheless, "Infrared Sauna" and "Infrared Therapy" are respectively a methodology and a terminology in the application of the infrared electromagnetic field spectrum to the human body. There are claims of detoxification which lack scientific evidence. There are at least 48 scientific or medical articles on "Infrared Sauna", 327 on "Far Infrared Therapy" and over twenty one thousand on "Infrared Therapy" some of which investigate health benefits, such as prophylactic physiotherapeutic treatment schemes, appetite loss and depression, cardio vascular system improvements, and Photothermal Therapy.
Infrared tracking, also known as infrared homing, refers to a passive missile guidance system, which uses the emission from a target of electromagnetic radiation in the infrared part of the spectrum to track it. Missiles that use infrared seeking are often referred to as "heat-seekers" since infrared (IR) is just below the visible spectrum of light in frequency and is radiated strongly by hot bodies. Many objects such as people, vehicle engines, and aircraft generate and retain heat, and as such, are especially visible in the infrared wavelengths of light compared to objects in the background.
Electromagnetic radiation of wavelengths other than those of visible light were discovered in the early 19th century. The discovery of infrared radiation is ascribed to astronomer William Herschel, who published his results in 1800 before the Royal Society of London. Herschel used a glass prism to refract light from the Sun and detected invisible rays that caused heating beyond the red part of the spectrum, through an increase in the temperature recorded with a thermometer. These "calorific rays" were later termed infrared.
Electromagnetic radiation of wavelengths other than visible light were discovered in the early 19th century. The discovery of infrared radiation is ascribed to William Herschel, the astronomer. Herschel published his results in 1800 before the Royal Society of London. Herschel, like Ritter, used a prism to refract light from the Sun and detected the infrared (beyond the red part of the spectrum), through an increase in the temperature recorded by a thermometer.
The first discovery of electromagnetic radiation other than visible light came in 1800, when William Herschel discovered infrared radiation. He was studying the temperature of different colors by moving a thermometer through light split by a prism. He noticed that the highest temperature was beyond red. He theorized that this temperature change was due to "calorific rays" that were a type of light ray that could not be seen.
Radio frequency radiation is usually measured in kilohertz (kHz), megahertz (MHz), or gigahertz (GHz). Light is electromagnetic radiation that is even higher in frequency, and has frequencies in the range of tens (infrared) to thousands (ultraviolet) of terahertz. Electromagnetic radiation with frequencies in the low terahertz range (intermediate between those of the highest normally usable radio frequencies and long-wave infrared light) is often called terahertz radiation. Even higher frequencies exist, such as that of gamma rays, which can be measured in exahertz (EHz). (For historical reasons, the frequencies of light and higher frequency electromagnetic radiation are more commonly specified in terms of their wavelengths or photon energies: for a more detailed treatment of this and the above frequency ranges, see electromagnetic spectrum.)
An infrared interactive whiteboard is a large interactive display that connects to a computer and projector. The board is typically mounted to a wall or floor stand. Movement of the user's finger, pen, or other pointer over the image projected on the whiteboard is captured by its interference with infrared light at the surface of the whiteboard.
When the whiteboard surface is pressed, software triangulates the location of the marker or stylus. Infrared IWBs may be made of any material, no dry-erase markers are involved, and may be found in many settings, including various levels of classroom education, corporate boardrooms, training or activity rooms for organizations, professional sports coaching facilities, and broadcasting studios.
Visible light is an electromagnetic wave, consisting of oscillating electric and magnetic fields traveling through space. The frequency of the wave determines its color: is red light, is violet light, and between these (in the range 4-) are all the other colors of the visible spectrum. An electromagnetic wave can have a frequency less than , but it will be invisible to the human eye; such waves are called infrared (IR) radiation. At even lower frequency, the wave is called a microwave, and at still lower frequencies it is called a radio wave. Likewise, an electromagnetic wave can have a frequency higher than , but it will be invisible to the human eye; such waves are called ultraviolet (UV) radiation. Even higher-frequency waves are called X-rays, and higher still are gamma rays.
Electromagnetic radiation with a wavelength between 380 nm and 760 nm (400–790 terahertz) is detected by the human eye and perceived as visible light. Other wavelengths, especially near infrared (longer than 760 nm) and ultraviolet (shorter than 380 nm) are also sometimes referred to as light, especially when the visibility to humans is not relevant. White light is a combination of lights of different wavelengths in the visible spectrum. Passing white light through a prism splits it up into the several colors of light observed in the visible spectrum between 400 nm and 780 nm.
Colloquially, radioactive materials can be described as "hot," and non-radioactive materials can be described as "cold." There are instances in which cold iodide is administered to people in order to prevent the uptake of hot iodide by the thyroid gland. For example, blockade of thyroid iodine uptake with potassium iodide is used in nuclear medicine scintigraphy and therapy with some radioiodinated compounds that are not targeted to the thyroid, such as iobenguane (MIBG), which used to image or treat neural tissue tumors, or iodinated fibrinogen, which is used in fibrinogen scans to investigate clotting. These compounds contain iodine, but not in the iodide form. However, since they may be ultimately metabolized or break down to radioactive iodide, it is common to administer non-radioactive potassium iodide to insure that metabolites of these radiopharmaceuticals is not sequestered by thyroid gland and inadvertently administer a radiological dose to that tissue.
Light is electromagnetic radiation within a certain portion of the electromagnetic spectrum. The word usually refers to visible light, which is the visible spectrum that is visible to the human eye and is responsible for the sense of sight. Visible light is usually defined as having wavelengths in the range of 400–700 nanometres (nm), or 4.00 × 10 to 7.00 × 10 m, between the infrared (with longer wavelengths) and the ultraviolet (with shorter wavelengths). This wavelength means a frequency range of roughly 430–750 terahertz (THz).
The main source of light on Earth is the Sun. Sunlight provides the energy that green plants use to create sugars mostly in the form of starches, which release energy into the living things that digest them. This process of photosynthesis provides virtually all the energy used by living things. Historically, another important source of light for humans has been fire, from ancient campfires to modern kerosene lamps. With the development of electric lights and power systems, electric lighting has effectively replaced firelight. Some species of animals generate their own light, a process called bioluminescence. For example, fireflies use light to locate mates, and vampire squids use it to hide themselves from prey.
The Advanced Diagnostic Ultrasound in Microgravity Study is funded by the National Space Biomedical Research Institute and involves the use of ultrasound among Astronauts including former ISS Commanders Leroy Chiao and Gennady Padalka who are guided by remote experts to diagnose and potentially treat hundreds of medical conditions in space. This study has a widespread impact and has been extended to cover professional and Olympic sports injuries as well as medical students. It is anticipated that remote guided ultrasound will have application on Earth in emergency and rural care situations. Findings from this study were submitted for publication to the journal Radiology aboard the International Space Station; the first article submitted in space.
"Brain Wave Vibration" is promoted as a mental and physical health enhancement technique developed by Ilchi Lee. According to Lee, brain waves are a type of vibration that has a significant effect on a person’s health and outlook on life. A form of moving meditation (head-shaking), the technique was described by one Body & Brain instructor: "By shaking your head and vibrating your body, you bring healing energy. You just need to close your eyes and turn your head right and left, right and left, focusing on the center of your brain and keeping a rhythm. Afterwards, you feel very rejuvenated!" As part of CNN's three-part investigation into controversy and lawsuits surrounding Dahn Yoga, Neurosurgeon Dr. Sanjay Gupta was asked about testimonials that Brain Wave Vibration "lowered blood pressure, corrected lazy eyes, [and] even reduced symptoms of multiple sclerosis." Gupta stated that the notion of vibrating the brain or other parts of the body to turn parts of the brain on and off is not grounded in science and that anecdotes are not empirically verifiable.
In 1977, Freeman became the first hospital to use ultrasound in diagnostic services and nuclear medicine.
In iodine-131 (radioiodine) radioisotope therapy, which was first pioneered by Dr. Saul Hertz, radioactive iodine-131 is given orally (either by pill or liquid) on a one-time basis, to severely restrict, or altogether destroy the function of a hyperactive thyroid gland. This isotope of radioactive iodine used for ablative treatment is more potent than diagnostic radioiodine (usually iodine-123 or a very low amount of iodine-131), which has a biological half-life from 8–13 hours. Iodine-131, which also emits beta particles that are far more damaging to tissues at short range, has a half-life of approximately 8 days. Patients not responding sufficiently to the first dose are sometimes given an additional radioiodine treatment, at a larger dose. Iodine-131 in this treatment is picked up by the active cells in the thyroid and destroys them, rendering the thyroid gland mostly or completely inactive.
Sonography (ultrasonography) is widely used in medicine. It is possible to perform both diagnosis and therapeutic procedures, using ultrasound to guide interventional procedures such as biopsies or drainage of fluid collections. Sonographers are medical professionals who perform scans which are then traditionally interpreted by radiologists, physicians who specialize in the application and interpretation of a wide variety of medical imaging modalities, or by cardiologists in the case of cardiac ultrasonography (echocardiography). Increasingly, clinicians (physicians and other healthcare professionals who provide direct patient care) are using ultrasound in office and hospital practice (Point of Care Ultrasound).
Light is measured with two main alternative sets of units: radiometry consists of measurements of light power at all wavelengths, while photometry measures light with wavelength weighted with respect to a standardised model of human brightness perception. Photometry is useful, for example, to quantify Illumination (lighting) intended for human use. The SI units for both systems are summarised in the following tables.
Isotretinoin, also known as 13-"cis"-retinoic acid (and colloquially referred to by its former brand name Accutane or Roaccutane), is a medication primarily used to treat severe acne. Rarely, it is also used to prevent certain skin cancers (squamous-cell carcinoma), and in the treatment of other cancers. It is used to treat harlequin-type ichthyosis, a usually lethal skin disease, and lamellar ichthyosis. It is a retinoid, meaning it is related to vitamin A, and is found in small quantities naturally in the body. Its isomer, tretinoin, is also an acne drug.
Ultrasound has been used in Medicine for close to half a century and its safety has been studied for almost the same period of time. In 1992, the US FDA first allowed the use of ultrasound at a frequency of 1.6 MHz in a toothbrush. In 1993, the American Institute of Ultrasound in Medicine (AIUM), in conjunction with the National Electrical Manufacturers Association (NEMA) developed the Output Display Standard (ODS), including the thermal index and mechanical index which have been incorporated into the FDA’s new regulations. These regulations limit the power output of these devices to a level low enough to avoid raising surrounding tissue temperature by more than 1 °C.
Light, or visible light, is a very narrow range of electromagnetic radiation of a wavelength that is visible to the human eye, or 380–750 nm which equates to a frequency range of 790 to 400 THz respectively. More broadly, physicists use the term "light" to mean electromagnetic radiation of all wavelengths, whether visible or not.
The American Cancer Society reported that "[t]here is no reliable scientific evidence that Gerson therapy is effective in treating cancer, and the principles behind it are not widely accepted by the medical community. It is not approved for use in the United States." In 1947, the National Cancer Institute reviewed 10 claimed cures submitted by Gerson; however, all of the patients were receiving standard anticancer treatment simultaneously, making it impossible to determine what effect, if any, was due to Gerson's therapy. A review of the Gerson Therapy by Memorial Sloan-Kettering Cancer Center concluded: "If proponents of such therapies wish them to be evaluated scientifically and considered valid adjuvant treatments, they must provide extensive records (more than simple survival rates) and conduct controlled, prospective studies as evidence". In 1959, the National Cancer Institute (NCI) again reviewed cases of patients treated by Gerson. The NCI found that the available information did not prove the regimen had benefit. Cancer Research UK states that "Available scientific evidence does not support any claims that Gerson therapy can treat cancer [...] Gerson therapy can be very harmful to your health."
IR radiation is more useful than the visible radiation for heating our body, because we absorb most of it, compared to a strong reflection of visible light. Penetration depth of infrared radiation in our skin is dependent of wavelength. IR-A is the most penetrating, and reaches some millimeters, IR-B penetrates into the dermis (about 1 mm), and IR-C is mostly absorbed in the external layer of the epidermis (stratum corneum). For this reason the infrared lamps used for therapeutic purposes produce mainly IR-A radiation.
In infrared photography, the film or image sensor used is sensitive to infrared light. The part of the spectrum used is referred to as near-infrared to distinguish it from far-infrared, which is the domain of thermal imaging. Wavelengths used for photography range from about 700 nm to about 900 nm. Film is usually sensitive to visible light too, so an infrared-passing filter is used; this lets infrared (IR) light pass through to the camera, but blocks all or most of the visible light spectrum (the filter thus looks black or deep red). ("Infrared filter" may refer either to this type of filter or to one that blocks infrared but passes other wavelengths.)
Infrared homing is a passive weapon guidance system which uses the infrared (IR) light emission from a target to track and follow it. Missiles which use infrared seeking are often referred to as "heat-seekers", since infrared is radiated strongly by hot bodies. Many objects such as people, vehicle engines and aircraft generate and emit heat, and as such, are especially visible in the infrared wavelengths of light compared to objects in the background.
Photothermal therapy (PTT) refers to efforts to use electromagnetic radiation (most often in infrared wavelengths) for the treatment of various medical conditions, including cancer. This approach is an extension of photodynamic therapy, in which a photosensitizer is excited with specific band light. This activation brings the sensitizer to an excited state where it then releases vibrational energy (heat), which is what kills the targeted cells.