Laser: Laser Therapy LASER : LASER Light
Amplification by the
The photons and waves are all the same size (monochromatic) and the photons and waves are in phase (Coherent) The light can be collimated (non-divergent) and is brilliant (has a high power density) Laser & Light: Laser & Light
How the First Ruby Laser Works: How the First Ruby Laser Works Slide6: 1. High-voltage electricity causes the quartz flash tube to emit an intense burst of light, exciting some of the atoms in the ruby crystal to higher energy levels. Slide7: 2. At a specific energy level, some atoms emit particles of light called photons. At first the photons are emitted in all directions. Photons from one atom stimulate emission of photons from other atoms and the light intensity is rapidly amplified. Slide8: 3. Mirrors at each end reflect the photons back and forth, continuing this process of stimulated emission and amplification. Slide9: 4. The photons leave through the partially silvered mirror at one end. This is laser light.
DOSAGE , ENERGY DENSITY: DOSAGE , ENERGY DENSITY POWER: POWER Power is expressed in watts (W) however LLLT device outputs are so low the tend to be expressed in milli-watts (mW)
Average Powers are typically 30-100mW.
More power means shorter treatment times, deeper penetration and some argue, better results.
THE LASER DIODE: THE LASER DIODE The LASERS used in modern LLLT systems are made from semi-conductor materials. They are robust and reliable.
They do not produce round and collimated (straight) beams. They are often elliptical in shape and diverge.
PENETRATION: PENETRATION Penetration depends on wavelength
Shorter wavelengths (600nm-700nm) are absorbed within a couple of mm by hemoglobin, longer wavelengths (1,000nm + )are absorbed by fat and water
WHAT IS LASER THERAPY (Low Level Laser Therapy) LLLT: WHAT IS LASER THERAPY (Low Level Laser Therapy) LLLT Laser Therapy is the application of electromagnetic wave 600-1100nm (red and near infra-red light, 780-830nm) over injuries or lesions to improve wound / soft tissue healing and give relief for both acute and chronic pain Laser Therapy: Laser Therapy 1. Laser heating at very low energies--Biostimulation
2. Laser heating at very low energies--Coagulation, welding and hyperthermia.
Coagulation: Heating at 60-70oC causes contraction of tissue around bleeding vessels, which are then squeezed shut.
Welding: Laser energy can perform anastomosis and welding of tissues at typical of temperatures of 60-70oC
Hyperthermia: Laser heating at typical temperature 42.5-43.5oC is use for hyperthermia treament. Slide16: 3. Laser heating at medium energy- Vaporization. Sufficient heating can vaporize tissue, drill hold, and cut the ablate tissue.
4. High-energy laser pulses -Lithotripsy and photoablation.
Lithotripsy: Scattering of urinary stone by shock-wave generated by power full laser pulsess.
Photoablation: Short, energy laser pulses vaporize tissue with little thermal damage.
5. Non-thermal effect- therapy and tissue removal
Photochemical methods; Laser energy is absorbed either by the tissue it self or by dyes or drugs introduced in to the tissue. The laser energy triggers therapeutic photochemical reactions.
Photodisruption: Excimer laser removes tissue with no sign of thermal damage. Indications: Indications Dermatological disorder
Rheumatic disorders,particularly complaints due to over burden of the soft tissues
Degenerative articular disorders
Disorders which are an indication for acupuncture Slide18: Arthritis
Carpal Tunnel Syndrome
No loss of work during or after treatment May be used on most post-surgical cases
No documented cases of side effects
Laser Therapy is used to:: Laser Therapy is used to: - INCREASE THE SPEED, QUALITY and TENSILE STRENGTH OF TISSUE REPAIR
- GIVE PAIN RELIEF
- RESOLVE INFLAMMATION Contra-indication: Contra-indication Direct irradiation to the eyes
Shortly(4-6 months)after radiotherapy
Pregnancy or menstruation for irradiation in the abdominal region and the low back Dosage: Dosage Dermatological disorder j/cm2
scar (too soft) 3-6
Scar (too much keloid)and/or pain 0.1-0.5
Transplantation wounds 0.05-1
Herpes zoster 0.4-0.7 Dosage: Dosage Rheumatic disorder j/cm2
Myocytis 0.5-2 Dosage: Dosage Post traumatic disorder j/cm2
Ruptures of soft tissues 0.5-3
(ligament, capsules, muscles, tendons)
Edema 0.1-1.5 Benefits of laser therapy: Benefits of laser therapy Laser light increases production of prostaglandin and collagen fibrils, and accelerates cell reproduction during treatment of open wounds.
Reduces inflammation and pain from strain to muscle and tendon, tendon and periosteum, tendon and synovial membrane, tendon and bursa.
Reduces pain and inflammation, improves mobility of osteo-arthritis affected joints.
Increases micro-circulation to reduce pain and edema induced muscle fibre damage from over-taxation of the muscles (myositis).
Improves mobility of joint in association with manual treatment of contractures.
Treats acne, roseacea and eczema.
Direct stimulation of acupuncture points
Laser therapy promotes rapid healing, enhances cell growth, prevents scar tissue formation, reduces inflammation and pain associated with sprains, ligament and capsular injuries. TATTOO REMOVAL MADE EASIER WITH NEW LASER THERAPIES(http://www.asds-net.org/tatoo.htm): TATTOO REMOVAL MADE EASIER WITH NEW LASER THERAPIES(http://www.asds-net.org/tatoo.htm) NEW YORK (October 27, 1999) - Once seen as an identity or hallmark of bikers and street gangs, tattoos are now part of American mainstream culture. In fact, the number of tattoo studios has grown from 300 to over 4,000 nationally in the past 20 years. While some people keep their tattoos for life, many people regret their decision to decorate their body and want them removed. UNIVERSITY OF MARYLAND EYE SPECIALISTS OFFER NEWLY- APPROVED LASER TREATMENT FOR MACULAR DEGENERATION (http://www.umm.edu/features/macular.html): UNIVERSITY OF MARYLAND EYE SPECIALISTS OFFER NEWLY- APPROVED LASER TREATMENT FOR MACULAR DEGENERATION (http://www.umm.edu/features/macular.html) The treatment, known as Photodynamic Therapy (PDT), uses the intravenous drug verteporfin in combination with a low-intensity laser to halt the destructive effect of abnormal blood vessels under the retina, found in the “wet” form of macular degeneration. About 20 percent of patients with macular degeneration have the “wet” type, which is the most severe form of the disease. The abnormal vessels can damage the macular region of the retina and, if left untreated, can result in blindness. Laser Therapy & Intense Pulsed Light Treatments(http://www.goldskincare.com/laser.htm) : Laser Therapy & Intense Pulsed Light Treatments(http://www.goldskincare.com/laser.htm) Remove Hair
Remove Varicose & Spider Veins, Age Spots, Freckles, Birthmarks, Port Wine Stains
Diminish Fine Lines, Wrinkles & Scars
Remove Varicose & Spider Veins, Age Spots, Freckles, Birthmarks, Port Wine Stains: Remove Varicose & Spider Veins, Age Spots, Freckles, Birthmarks, Port Wine Stains Varicose Veins before Varicose Veins after Freckles before Freckles after Diminish Fine Lines, Wrinkles & Scars: Diminish Fine Lines, Wrinkles & Scars Before After Laser Therapy treatments(http://laser.uk.com/treatment/index.html): Laser Therapy treatments(http://laser.uk.com/treatment/index.html) WOUNDS: WOUNDS Treat recent wounds for 1 min per area with cluster probe at 20 Hz.
Treat chronic non healing wounds for up to 2 mins per area at 5KHz. Aim to treat surrounding soft tissues as well as the wound itself.
It may take 2 - 4 'clusters' to treat the both wound bed and the surrounding soft tissues. Use transparent thin film (cling-film) over ulcers, pressure sores and wounds and, without causing undue pain, maintain contact with site to be treated if possible. Clean probe after use with a surgical spirit wipe.
There are normally no adverse effects from Laser Therapy, however, patients occasionally experience mild discomfort / ache after treatment. This is due to a re-stimulation of the inflammatory phase and should settle down after 24 - 48 hours. WOUNDS: WOUNDS Day 1 Day 21 Day 42 Treat each tender point with the 100mW laser probe: Treat each tender point with the 100mW laser probe. Palpate for any changes (eg: reduction in pain, change in tissue texture, relaxation of muscle, etc). If there is no response, then treat the tender points again. Palpate for any changes and repeat once more if necessary. Then treat the surrounding soft tissue with the cluster probe for 1-2 mins per area depending on the build of the patient
Treat each tender point with the 100mW laser probe HOW TO CHOOSE A LASER: HOW TO CHOOSE A LASER - Infra-Red (30mW average power or more) for musculoskeletal
- Visible Red (620nm-780nm) for wound healing (10-30mW)
- Wide range of pulse frequencies (2.5Hz to several thousand Hz)
- Point finder to find muscle trigger points
- Timer Neurofibromatosis(http://www.madtecint.com/home_e.htm): Neurofibromatosis(http://www.madtecint.com/home_e.htm) untreated Laser-treated Indications : Indications Sports medicine and orthopaedics
traumatic conditions of muscles and nerves
Treatment of wounds
healing of wounds
acne. A: Examples of lasers which can be used in medicine:: A: Examples of lasers which can be used in medicine: Laser name Wavelength Pulsed/continuous Use in medicine.
Crystalline laser medium:
Ruby 694 nm p holograms, tattoo coagulation, hair removal Nd:YAG 1 064 nm p coagulation, dentistry Ho:YAG 2 130 nm p surgery, root canal Er:YAG 2 940 nm p surgery, dental drill KTP/532 532 nm p/c dermatology Alexandrite 720-800 nm p bone cutting, hair removal
Slide40: Semiconductor lasers: GaAs 904 nm p biostimulation GaAlAs 780-820-870 nm c biostimulation, surgery InGaAlP 630-685 nm c biostimulation
Liquid laser: Dye laser (tuneable) p kidney stones Rhodamine: 560-650 nm c/p PDT, dermatology Slide41: Gas lasers: HeNe 633, 3 390 nm c biostimulation Argon 350-514 nm c dermatology, eye CO2 10 600 nm c/p dermatology, surgery Excimer 193, 248, 308 nm p eye, vascular surgery Copper vapour 578 nm c/p dermatology The instruments of laser therapy: The instruments of laser therapy 630nm (red, visible light) to 830 nm (infrared, invisible light).
red light is generally absorbed by the surface
Infrared can penetrate deeper into the tissue
Both solid-state lasers and gas lasers
Gas lasers are Helium-Neon lasers
Solid-state lasers (usually Gallium-Arsenid, GaA)
Stationary Instruments "low-level" or "cold-laser Scanners : Scanners treatment of larger areas of skin
more than one laser diode
Table Instruments 3mW to 300mW
Mobile Instruments: Mobile Instruments 3mW to 300mW
Some machines have a few fixed frequencies
10mW to 150mW
infrared, invisible light GaA/As-Diode (780nm to 830nm).
require a construction licence and need to be in the 3b class of lasers Laser Safety Considerations: Laser Safety Considerations Laser Hazards Eye hazards such as retinal or cornea burns.
Skin hazards such as burns.
Electrical hazards from high voltage equipment.
Clasification: Clasification Class I: Power do not exceed the maximum permissible exposure(MPE) for the eye
Class II: Visible laser beams with power levels up to 1 mW. The eye is protected by the blinking reflex.
Class IIIa: Same as class II but use for power level up to 5mW and with laser beams which are expanded.
Class IIIb: Power level up to 0.5W. Direct viewing of the beam is dangerous.
Class IV: Power levels > 0.5W. Extremely hazardous. Eye hazards such as retinal or cornea burns: Eye hazards such as retinal or cornea burns NEVER point a laser at someone's eyes no matter how low the power of the laser. one watt laser beam entering the eye can be focused to 100,000 watts per square centimetre of power at the retina RETINAL INJURY IS PERMANENT Skin hazards such as burns: Skin hazards such as burns With higher power lasers a burn can occur even though the flinch reaction may rapidly pull the affected skin out of the beam. These burns can be quite painful as the affected skin can be cooked and forms a hard lesion that takes ages to heal. Exposure of the skin to high power laser beams (1 or more watts) can cause burns. At the under five watt level, the heat from the laser beam will cause a flinch reaction before any serious damage occurs.The sensation is similar to touching any hot object, you tend to pull your hand away or drop it before any major damage occurs.
Laser Link: Laser Link http://www.derm.ubc.ca/laser/llsc.html