Infrared Radiation Therapy PDF

Infrared Radiation (IRR) Definition: Infrared radiations (IRR) are electromagnetic radiation that lies within that part of the electromagnetic spectrum between visible light and microwave radiation. The radiation characterized by wavelength extended from 760nm to 1 mm. Infrar...

Infrared Radiation (IRR) Definition: Infrared radiations (IRR) are electromagnetic radiation that lies within that part of the electromagnetic spectrum between visible light and microwave radiation. The radiation characterized by wavelength extended from 760nm to 1 mm. Infrared radiation is a superficial thermal agent. Any heated body emits infrared radiations that can be subdivided into three regions or bands, A, B and C according to its wave length, see table (1). Table (1): Classification of IRR 1 Production of infrared radiations Infrared radiations are produced as a result of molecular motion within heated materials or generators. These generators are heated by passage of electrical current through wire. An increase in temperature above absolute zero results in the vibration or rotation of molecules within the matter, which lead to the emission of infrared radiations. Sources of infrared radiations Infrared sources can be either natural (for example, the sun) or artificial. The artificial sources are classified as: 1- Luminous I.R sources 2- Non-luminous I.R sources 1- Luminous I.R sources: Luminous lamps are produced by electrically heated filament made of tungsten in an evacuated glass bulb which contains an inert gas at a low pressure. 2 Emission: luminous sources emit mainly: 70% short IR 24% long IR 5% visible light 1% UV rays. Disadvantages: luminous generators emit infrared rays, visible light as well as ultraviolet rays. Advantage:  Require less time to get heated up for production of IRR.  Penetrate more compare to Non-luminous. 2- Non-luminous I.R sources: Non-luminous sources consist of spiral coils of metal wire wrapped around non-conductive material. Non-luminous sources don’t penetrate more deeply. 3 Emission: non-luminous sources emit mainly long IR radiation (with about 10% short IR). 4 Disadvantages: Non-luminous generators take some time to get heated up for the production of infrared radiations, so they should be switched on at least 5 minutes before the treatment. Advantage: Non-luminous generators provide infrared rays only. Absorption and penetration of IRR: IRR is strongly absorbed near the skin surface when it is applied perpendicular to the skin, heat is transmitted rather than reflected. The heat is carried to the deeper tissues by conduction and by the circulating fluids. The absorption of IRR and the maximal penetration of the rays will depend upon the following variables: 1. Wave length of the rays: - As the wave length decreased as in the short infrared region, the depth of penetration increased - As the wave length increased, the depth of penetration decreased 2. Angle of incidence of the rays As the rays angle away from perpendicular, the rays are reflected away from the surface and intensity decreased. 3. The intensity of the emitting source The intensity of heating of IR is controlled by changing the distance of the lamp from the patient. 5 Physiological Effects of IRR 1- Cutaneous vasodilatation Heating with IRR causes local cutaneous vasodilatation. The vasodilatation starts after a short latent period of 1 to 2 minutes, and appears as an irregular patchy erythema. The rate and degree of erythema depend on the rate and degree of heating. 2- Increase in metabolism Increase temperature by IRR leads to increased metabolic activities within superficial tissues, and as a consequence improved cell function and tissue healing. 3-Increase in tissue extensibility Heating with IRR leads to increase the extensibility of connective tissue and therefore is used prior to stretching exercise to increase range of motion, especially if motion is restricted by shortening of superficial tissues such as skin and fascia. 4-Pain control The heat produced by IRR leads to relief of pain by: Decreased activity of muscle spindle leads to decrease muscle spasm and muscle relaxation. Removal of waste products as a result of improving circulation and increase venous return thus removing the source of pain stimulation Therapeutic Uses (indications) of IRR 1- Relieve of pain 2- Reduction of muscle spasm 3- Acceleration of healing (stimulation of incisional wound healing) 4- Sub-acute and chronic inflammation of musculoskeletal system 5- Prior to stretching and mobilization exercises 6 6. Reduction of Sub-acute and chronic edema as IRR helps in absorption of exudates. 7. It can be used before application of Electrical stimulation current to make skin better conductor Contraindications of IRR 1- Acute inflammation 2- Infected tissue 3- Lack of local thermal sensitivity 4- Impaired local circulation 5- Over pregnant uterus 6- Eyes 7- Local areas of recent bleeding 8- Over or near malignant tissue 10-Unreliable patients: - very young or very old people 11- Following recent deep X-ray therapy IRR rays shouldn’t be given for 3 months as deep X-ray reduce sensation over the exposed area and thus get burned 7  Clinical Application Preparation of patient 1- Place the patient in a comfortable position. Drape the body part so that only the area to be treated is exposed. 2- Inspect the area to be treated for any contraindications 3- Explain to the patient the sensation that should be experience (mild to moderate warmth) 4- Clean the area of any sweat, dirt, or oils and remove any jewelry to prevent the concentration of heat. 5- The skin to be treated is examined and the thermal sensation is tested. Thermal sensation is tested through the application of two test tubes one contains hot water and the other contains cold water and ask the patient to distinguish between them. Setup and application 1- If a non-luminous lamp is chosen, switch it on at least 5 minutes before treatment to allow time for it to warm up and reach its maximum emission. A luminous lamp needs no warm up. 2- Place the lamb so that the distance from the source of heat is approximately 50-75 cm away from the patient. Practical Note: Due to the increased absorption of the longer wave lengths by the top layers of the skin, the non-luminous units apparently feel hotter than do the luminous ones at equal distances and power levels. So, place non-luminous lamps at slightly greater distances (75-90 cm). 3- Adjust the lamp so the energy will strike the tissue at a right angle. This ensure maximum absorption. 4- Instruct the patient to not to touch any part of the lamp or to move during treatment and to report any discomfort or excessive heating. 8 5- The intensity of heating of IR is controlled by changing the distance of the lamp from the patient. 6- The duration of treatment is from 10-15 minutes as it is only part of a treatment, not a treatment in itself. 7- After termination of treatment inspect the treated area. Usually there is mottled erythema without any discomfort. 9