INFRA RED BY PT JITENDRA

INFRA RED IR has no color, it is detected by warmth IR is emitted from any heated body Its wavelength is higher than visible light IR has a wavelength of 760nm to 1mm

ELECTRO MAGNETIC SPECTRUM INITIAL WAVES WAVELENGTH R RADIOWAVES 0.1 MM TO 100 KM I INFRA RED 750 NM TO 0.4 MM V VISIBLE LIGHT 400 NM TO 750 NM U ULTRA VIOLET 10 NM TO 400 NM XG X-RAY / GAMMA RAYS 0.01 PM TO 100 NM

IR CLASSIFICATION OF IR IR A IR C 760- 1400 NM 3000NM – 1MM IR B THERAPEUTIC IR C 3000NM – 1MM NON THERAPEUTIC IR B 1400 – 3000 NM THERAPEUTIC

Heated material produce IR radiation Higher temperature are associate with higher frequency, & shorter wavelength TEMP α 1 / WAVELENGTH & TEMP α FREQUENCY If short IR is to be produced material must not be burnt by higher temperature used. Convenient method is to heat a resistance WIRE by passing an electric current through it Electrical heater is made up of coil of suitable resistance WIRE , i.e. nickel- chromium alloy, wound on ceramic insulator

IR LAMPS NON - LUMINOUS GENERATOR LUMINOUS GENERATOR

NON LUMINOUS GENERATOR (i.e. coil heater) IR source is a coil of WIRE wrapped around a cylindrical ceramic insulator In this heaters WIRE glows red, thus giving some radiation in visible spectrum Some IR lamps for therapy have WIRE embedded in insulation ceramic, ceramic is heated because of lamp which emits IR so that little or no visible radiation is emitted

Heater WIRE can also be mounted behind a metal plate or inside a metal tube which does not become hot spot but emits IR in same way IR emitter is placed at focus of reflector to produce an uniform wave

If reflector is more spherical instead of convergence of beam, it will be diverge, this is usually adapted in clinic. Reflector & emitter are mounted on a mobile metal stand which can be adjusted to alter height & angle of reflector or emitter. When lamps are switched on they require time to warm up because of thermal inertia of mass of metal & insulating material that has to be heated

Small lamps may take about 5 min Small lamps may take about 5 min. but large ones may take up to 15 min to reach maximum emission Lamps with an exposed coil give off a red glow although they are collectively designated as “ non-luminous” sources With non-luminous Exposure is in Long IR wavelength range

LUMINOUS GENERATOR (i.e. bulb) They consist of a tungsten filament in a large glass envelope which contains inert gas at low pressure. Part of inside of glass bulb is silvered to provide a reflector Works on same principle as a simple electric light bulb Filament is heated to a high temperature around 3000 by a current passed through it

So gives out continuous spectrum in IR & visible region Oxidation(burnt) does not occur because of no oxygen, only part of inert air Radiation extends from SHORT IR to visible light to the UVR. UVR is absorbed in glass Luminous generators are sometimes called RADIANT HEAT as they emit both IR & visible light

POWER SMALL LAMPS (BOTH) 250-500 WATT LARGE, NON LUMINOUS 750-1000 W LARGE , LUMINOUS 750-1500 W Larger lamps are used to treat extensive area , but same effect can be achieved by placing small three lamps in a row

EMISSION NON LUMINOUS 3000 – 4000 NM (LONG IR ) LUMINOUS SHORT IR 5% VISIBLE 1% UVR

PENETRATION & ABSORBTION IT DEPENDS UPON: STRUCTURE VASCULARITY PIGMENTATION OF SKIN WAVELENGTH OF RADIATION

DEPTH OF PENETRATION Depth of penetration: it is depth at which approximately 63% of radiation energy has been absorbed & 37% remains 3000 nm depth of penetration is 0.1mm Increasing penetration with decreasing wavelength in short IR to a maximum penetration depth of 3 mm at 1000 nm

Technique of application Patient POSITION : SUITABLE, WELL SUPPORTED, WITH AREA TO BE TREATED EXPOSED. EXPLANATION : EXPLAIN NATURE AND EFFECT OF TREATMENT TO PATIENT EXAMINATION AND TESTING : EXAMINE THE SKIN TO BE TREATED AND TEST THERMAL SENSATION.

APPARATUS : IF A NON – LUMINOUS LAMP IS CHOOSEN SWITCH IT 5 MIN BEFORE TREATMENT STARTS TO ALLOW A TIME TO WARM UP LUMINOUS LAMP DOES NOT REQUIRE WARM UP TIME.

SETTING UP EXPOSE THE SKIN TO BE TREATED COVER EYE, A TOWEL IS SUFFICIENT POSITION LAMP IN SUCH A WAY THAT RAYS STRIKE AT 90 DEREE TO SKIN SET LAMP AT 60-75 CMS FOR LARGE LAMP (750 TO 1000 WATTS) SET LAMP AT 40-45 CMS FOR SMALL LAMP

INSTRUCTIONS AND WARNING ADWISE PATIENT OF REQUIRED LEVEL OF HEAT AND IT MUST NOT BE HOT AS IT BURN. ASK PATIENT NOT TO TOUCH ANY PART OF LAMP OR TO MOVE DURING TREATMENT ALERT THERAPIST IF IT IS MORE THAN COMFORTABLE LEVEL OF HEATING.

APPLICATION INTENSITY IN MOST IR LAMP IS CONTROLLED BY DISTANCE. DOUBLING THE LAMP TO SKIN DISTANCE REDUCE THE INTENSITY (WCM-2) TO ONE QUARTER TRIPLING THE LAMP TO SKIN DISTANCE REDUCE THE INSTENSITY TO ONE NINTH

TERMINATION AT THE END OF TREATMENT SKIN SHOULD BE CHECKED ON PALPATION IT LOOKS MILD OR MODERATELY WARM MODERATE ERYTHEMA SHOULD BE VISIBLE. ERYTHEMA TENDS TO VARY WITH SKIN COLOR, NOT JUST TEMPERATURE.

PHYSIOLOGICAL EFFECT PHYSIOLOGICAL VASODILATATION SWEATING SENSATION INCREASE IN METABOLISM NEUROLOGICAL RELAXATION DECREASE MUSCLE TONE DECREASE OEDEMA DECREASE MUSCLE SPASM ANALGESIA

PHYSIOLOGICAL VASODILATATION Local cutaneous vasodilatation due to liberation of chemical vasodilators, histamine & similar substances Vasodilatation starts after latent period of 1-2min, it is mainly because of arteriolar vasodilatation

With IR regular patchy appearance Local Erythema may last up to 30 min after IR radiation has stopped CHRONIC CHANGES Destruction of erythrocyte, releasing pigments & causing brown discoloration of skin

THERAPEUTIC USES OF IR PAIN RELIEF REDUCTION OF MUSCLE SPASM ACCELERATION OF HEALING & REPAIR PROMOTE TISSUE EXTENSIBILITY REDUCE JOINT STIFFNESS TO REDUCE OEDEMA TO PROMOTE SWEATING AS ANTIDOTE TO UVR

CHOICE OF LUMINOUS & NON LUMINOUS LAMP Electrically heated wire embedded in ceramic and backed by reflector Gives only IR Produce long IR (3000-4000nm) Superficial heating LUMINOUS HEAT LAMP Electrically heated filament in an evacuated glass bulb, with silver inner surface Gives IR + visible rays Produce Short IR (1000nm) Deep heating compare to non luminous

LUMINOUS HEAT LAMP Penetrates more compare to non luminous More efficient tissue heating Therapeutic effect is mostly due to heating NON LUMINOUS LAMP Does not penetrate more deeply Mostly absorbed in skin Therapeutic effect is mostly due to sensory heating

DANGERS BURNS Risk of burns can be reduced by: Testing patient’s ability to differentiate heat levels Ensure sufficient distance of lamp from the skin Adequate warning to patient Checking effect of skin during treatment PT can feel skin or place hand under lamp Metals should be removed

REDUCE OR ALTER PERIPHERAL BLOOD FLOW Increased local flow during heating during heating must be sufficient enough to dissipate heat Arterial disease atherosclerosis, arterial injury or skin grafting is not treated with IR After IR radiation, & following radiotherapy pt should not be treated with IR

INFECTION Do not apply heat over local infection TUMOR With heating tumor cell grow more SKIN INFLAMMATORY CONDITION Skin condition become more worst after applying IR

EYE DAMAGE Prolonged & extensive exposure to IR leads to Cataracts E.g. in workers of glass factory or furnace men

contraindication Defective cutaneous circulation Acute skin disease Impaired sensation Analgesic & narcotic drug (it raises pain threshold) Blood pressure abnormality Severe cardiac condition Following radiotherapy Superficial infections Tumor Metal in treatment area

TECHNIQUE OF APPLICATION OF IR Patient Apparatus Setting up Instruction & warning application

patient Position: suitable, well supported Expose area to be treated Explanation: explain nature & effect of treatment to pt Examination & testing: examine skin to be treated , rule out for contraindication,& test thermal sensation

apparatus If non luminous lamp is chosen , switch it for at least 5 min before treatment to allow time for it to warm up & reach its maximum emission Luminous lamp does not require any warm up

Setting up Expose skin Cover eye Place lamp in such a way that radiation strikes at right angle Set a lamp at appropriate distance 60-75 cm for large 750 or 1000 w 45-50 cm for smaller ones

Instruction & warnings Heat should be of require level It must not be hot to make burn Pt should not touch any part of lamp

application Intensity of most IR lamp is controlled by distance of lamp from skin Inverse square law Doubling the distance reduces intensity by one quarter Tripling distance reduces intensity to one ninth part

Adjacent area can be protected from heating by placing towel. Therapist should check level of heating on completion of set up & again after 5-8 min If require reduce intensity of lamp by increasing distance of lamp from skin DURATION OF TREATMENT 10-15 min REMEMBER THAT IR IS A PART OF TREATMENT NOT TREATMENT ITSELF

THANK YOU