Infrared Radiation Microwave Ultraviolet Radiation Infrared Infrared lamps

Infrared Radiation, Microwave, Ultraviolet. Radiation

Infrared | Infrared lamps emits electromagnetic radiation within frequency range heat absorbed by the matter. | IR is emitted by many sources (e. g. the sun).

Physical Characteristics | IR radiation has wave length of 770 nm to 1 mm. | Part of EM spectrum lying between visible light and microwave. | Divided into 3 bands: 1 - IR-A: 770 to 1400 nm 2 - IR-B: 1400 to 3000 nm 3 - IR-C: 3000 to 106

Types of IR radiation (Used clinically) | Luminous (visible) | Non luminous (invisible) IR lamps available emit radiation of wave length 780 and 1500 nm.

: Physical Behavior of IRR | Reflected | Absorbed | Transmitted | Refracted | Diffracted

: Physiological Effects of IRR | Metabolic effect: | Increases metabolic activity. | Circular effect: | Increases blood flow superficially. | Neurological effects: | Increases nerve conduction velocity. | Cellular effects: | Increases elastic fibers in upper dermis. | Increases ground substance. | Alters composition of amino acid proteins.

Clinical (Therapeutic) Effects of IRR: | Pain | Muscle spasm | Joint stiffness | Tissue healing | Circulation | Edema | Skin lesion | Others: before stretching, mobilization, traction, massage, exercises, E. S. , bile pigments.

Modes of Heat Transfer | Radiation (lamp to body) | Convection and conduction ( through the body) Dosage | Sensory report of the patient | Adjusted by: | Changing power output of the lamp | Distance of lamp | Angle of incidence

Time of Application 10 – 20 minutes.

Microwave | E. M. R. between the radio waves and infrared. | Wavelength between 1 m and 1 cm. | Frequency between 30 MHz – 30 GHz. | Available since 1930 | Effective method of heating (highly vascular tissue)

. Production of M. W | High frequency oscillating current. | Magnetron to generate oscillating currents directly from high velocity electron motion. | Coaxial cable. | Antenna (emitter). | Intensity control. | Meter mean of switching. | Can be continuous or pulsed.

Ultraviolet Radiations | Physical properties of U. V. radiations: | Electromagnetic radiations. | Frequency 7. 5 x 1014 to over 1015. | Wavelength 400 nm to below 290 nm. | Lies between x-ray and visible light. | Divided into three bands, A, B and C band. | A and B bands reach the earth, whereas C band is filtered by the ozone layer | Produce physiological effect by non thermal mechanism

| Most significant source of U. V. is the sun. | Obeys inverse square and cosine law. | Intensity is proportional to the power of lamp output. | Deepest penetration with high intensity, long wavelength and lower frequency. | U. V. A penetrate farthest | U. V. B and U. V. C are less deep. | Less deep penetration if skin is thick or dark.

Physiological Effects of U. V. R 1 - Erythema production: | Redness. | Depends on the amount of U. V. | Types of erythema. | High dose destructive.

2 - Tanning: Delayed pigmentation of the skin * Caused by: * Increase production and upward migration of melanin granules * Oxidation of premelanin in the skin * Protective response of the body

3 - Epidermal hyperplasia | Thickening of the superficial layer of skin. | 72 hours after exposure. | Persists for several weeks. | Protective mechanism. 4 - Vitamin D Synthesis | Conversion of provitamin D to vitamin D. 5 - Other Effects | Bactericidal effect.

Erythemal Respons | Suberythemal dose (SED) : | No change in 24 h after exposure. | Minimal erythema dose (MED) : | Smallest dose erythema (8 h) | Dissapears within 24 hours

| First-degree erythema (E 1) : | Definite redness with mild desquamation. | Appears within 6 hours. | Lasts for 1 – 3 days | About 2. 5 times MED | Second degree erythema (E 2) | Intense erythema with edema, peeling and pigmentation. | Appears within 2 hours or less. | Like severe sun burn. | About 5 times MED.

| Third degree erythema (E 3) : | Erythema with severe blistering, peeling and exudation. | Dose about 10 times MED

Clinical Indications for U. V. radiation | Skin disorder | Psoriasis and other dermatological conditions | Non pulmonary T. B. | Healing wounds

Application Technique | Determine patient’s sensitivity to U. V radiation | Use the same lamp | Dose response assessment | Graded according to individual’s erythemal response

The End Good Luck To You All