Introduction to Low Level Laser Tara Hudye, B.Sc., DVM Who Am I? • Bachelor of Science, U. of R. 2000 • D.V.M., D V M Western College of Veterinary Medicine 2004 • Pending Certified Canine Rehabilitation Practitioner (CCRP), U. of Tennessee, July – December 2012 ((certification exam)) ▫ CCRP externship with Dr. Pinto, DVM, CCRP Currently employed at Lakewood Animal Hospital, Regina, Sk. k Myy Goal • • • • Science behind laser light and HOW it works Scientific studies Uses and clinical applications Safety for you! History of Laser In 1966, Dr. Endre Mester experimented with the effects of lasers on the skin. He applied laser energy to the backs of shaved mice: noted it did not cause cancer, YET the shaved hair grew back more quickly on the treated group compared t th to the untreated t t d group. How does it work? • • • • • L = Light A = Amplification S = Stimulated E = Emission R = Radiation Light g vs. Laser Light g • “Light” means electromagnetic radiation that is visible to the normal eye • Laser light is: 1) Monochromatic – all light produced by the laser is one wavelength of color 2) Polarized 3) Coherent – the light travels in a straight line So the result is…… • These properties allow the laser light to penetrate the surface of the skin with no heating effect, no damage to the skin, and no known side effects. • The light is absorbed by the mitochondria ▫  increased ATP levels ▫  DNA production ▫  changes in cell membrane permeability Physiological Effects and Biochemical Events within the Cell • 1) Analgesia • 2) Reduction in Inflammation • 3) Increase in microcirculation resulting in an acceleration in tissue repair and wound healing Analgesia How does photobiomodulation reduce pain?? • • • • • • • Increase beta endorphins Increase nitric oxide production Decrease bradykinin levels Ion channel normalization Bl k d Block depolarization l i ti off C C-fiber fib afferent ff t nerves Increase nerve cell action potentials Increase release of acetylcholine Inflammation Reduction How does photobiomodulation reduce inflammation?? • • • • • • • • Enhance ATP production and synthesis y p drainage g system) y Stimulation vasodilation (activates lymphatic Stabilize cell membranes Accelerate leukocytic activity Reduce interleukin 1 Increase lymphocyte response Increase angiogenesis Temperature modulation Accelerated Wound Healing How does photobiomodulation accelerate wound healing?? • All 4 stages of healing affected: inflammation, proliferation, remodeling d li and d maturation t ti • Increased fibroblast proliferation • 2-5 x increase in growth factor and DNA synthesis in fib bl t muscle fibroblasts, l cells, ll osteoblasts t bl t and d mucosall epithelial ith li l cells • Greater healed wound tensile strength in soft tissue and connective injuries Wound Healing g • Mester et al. p 100 clinical cases • Reported with healing wounds • Results: marked increase in collagen formation, increase vasodilation and accelerated DNA synthesis • Haina et al • Conclusion: the beneficial effects of laser therapy in the treatment of slow healing wounds may be due to promotion i off granulation l i and d epithelization D 2 Day D 7 Day D 9 Day Further Uses • • • • • • • Acral lick granulomas Clipper burn/catheter site irritation Self trauma (tail biting) Hot spots Gingivitis/periodontal disease (post dentals) Acute and chronic otitis Burns Neurological g Implications p • Spinal Cord Injuries • Rochkind (1988) performed laminectomy and transection of the spinal i l cord d att T12 T12-L1 L1 in i 17 1 d dogs. An A autograft t ft off the th sciatic i ti nerve was implanted in the injured site.  10 dogs received laser x 20 days; stood between 7-9 weeks and walked in 9-12 weeks. weeks  7 dogs who did not receive laser  paralyzed. ** New axons and blood vessels, originating in the spinal tissue, extended into the graft! graft!** • Low level laser therapy reduces time to ambulation in dogs after hemilaminectomy: A Preliminary Study ▫ Draper et al, Journal Small Animal Pract, 2012, August 53 (8): (8) 465-9 6 py, in combination with ▫ Conclusion: Low level therapy, surgery, decreases the time to ambulation in dogs with T3-L3 myelopathy secondary to intervertebral disc herniation. herniation Nerve Dysfunction • • • • • Femoral nerve paralysis History: Oakley 8 year MN Boxer March 2011: diagnosed with severe bridging spondylosis in multiple areas of spine December 2011- July 2012: progressive clinical signs of severe abduction of right limb, absent patellar and cranial tibial reflex, knuckling • Right femoral nerve paralysis with muscle atrophy Treatment - - Physical rehabilitation 2x week x 2 weeks, then weekly Sessions include combination of massage ROM exercises massage, exercises, therapeutic exercises and laser Laser protocol: laser L4-L6, T10-T12 and L1-L3 right and l ft dose left, d 8 joules/cm j l / 2; total t t l joules 3600 Visit 3 (6 days later) - Owner states Oakley is able to place right limb in proper position on stairs approximately i l 25% off time i compared to nil - In clinic: 50% decrease of knuckling and abduction on stance and walk VISIT 5 - Sits in proper position 20-25% of the time VISIT 8 - Decreased knuckling g byy 9 90% Able to ambulate stairs properly VISIT 9 (28 days) – cleared a 2 inch cavaletti rail 3 times!!! Orthopedic/Musculoskeletal p Use • Arthritis • Sports related injuries – iliopsoas injury, medial collateral ligament i j injury, bi bicepital it l tendonitis, t d iti carpall h hyperextension, t i etc. t • Lameness – e.g. CrCl injury- surgical and conservative/nonsurgical • Fractures – delayed or non union ▫ Slow l h healing li ▫ Poor apposition ▫ Routine part of post surgical protocol Osteoarthritis Pain Management 1) Induction Phase: ideally every other day until a response is noted 2) Transitional Phase: once a response is noted, start to decrease the frequency of t t treatments t 3) Maintenance Phase: every 3-4 weeks  Trust the owners observations of the patient at home to determine the maintenance treatment frequency. +/- increase frequency in winter Post Operative Pain Control • Post operative application to surgical site: • • • Reduces edema Increase rate of healing Decreases pain Post TTA (cruciate repair) - No contraindications of treating over implants, however light cannot go through it so cross over it to treat the soft tissues around it. - Dosage: 8-10 J/cm2 (stifle ) 3-4 joules/cm2 (incision) Summaryy of Biological g Effects • • • • • • • • • Faster wound healing Reduction of fibrous (scar) tissue formation Anti-inflammation Analgesia (anti pain) b activityy Increased metabolic Improved nerve function Accelerated tissue repair and cell growth Improved vascular activity Trigger points and acupuncture Parameters of Treatment • Photons penetrate tissue as a function of wavelength, power and time • Treatment parameters are based on : ▫ size of animal ▫ type of condition 1) Superficial: wounds or post surgical incisions need a lower dose, thus the power and time is less ▫ The size of the patient is not a large factor in determining the dose 2) Deep tissue and musculoskeletal: size of patients is important E.g.: Hip OA treatment – 20kg dog needs 6 J/cm2 -- 50kg dog needs 10 J/cm2 due to increased depth needed for adequate treatment - Dosages g • Analgesia effect: - Muscle pain: 2-4 joules/cm2 - Joint pain: 4-8 joules/cm2 • Anti-inflammatory A ti i fl t effect: ff t - Acute/Subacute: 1-6 joules/cm2 - Chronic: 4-8 jjoules/cm2 • Circulatory effect: - 1-3 1 3 joules/cm2 Record Keeping p g • • • • Anatomic location Continuous or pulsed Dosage required e.g.: 6 J/cm2 Total joules delivered: ▫ 3 x 5 inch index card= 100 cm2 Keep in mind….. • Think Thi k about b t shaving h i th the animal i l - 50-99% of the light can be absorbed by hair - Melanin: black or brown skin dogs need higher dose (2550% increase depending on the wavelength used) • Water - Area must be dry since water absorbs the photons • Wash iodine off area (post surgical) - Iodine can absorb the photons Protect your eyes! • Damage may occur to the retina if the laser shines into the area • Remember: SCATTER! Contraindications • Eyes, testicles g g • Hemorrhaging • Epiphysitis (over growth plates) • Melanomas/sarcoids l / d and d other h malignancies **leave unknown lumps and bumps alone** l ** • Pregnancies • Tattoos (can heat up and become uncomfortable) Class 3B vs. Class 4 Laser: • All therapy treatments that can be administered with a Class 4 Laser can also be effectively administered with a Class 3B Laser. While the Class 4 Laser is a higher powered laser, the higher power does not provide any different treatments than the Class 3B Laser. Pros & Cons Class 3B Class 4 • $ • Keep still • More time to achieve target dose  time consuming in multiple target areas • $$$ • Applicator head must be moving all the time • 3 inches/second • Potential of burning, especially dark hair follicles or pigmented skin Questions?