Therapeutic lasers aren’t quite a pain-management magic wand, but their adherents say they come close. When used properly, these light-emitting diodes perform virtual miracles in patients dealing with chronic pain, going through physical therapy or healing from trauma or post-surgical wounds—and they’re even proving to have regenerative effects, too.
Photos courtesy of CAO Group Inc.
A burn victim, top, and two weeks later after being treated with a diode laser.
At the recent American Society for Laser Medicine and Surgery conference in Phoenix, researcher Juanita Anders, Ph.D., of the Uniformed Services University of the Health Sciences presented a study that showed how lasers trigger nerve growth.
“The researchers showed that 980-nanometer wavelengths caused actual sprouting of nerves in a diabetic cell culture,” reports Ron Riegel, DVM, president of the American Institute for Medical Laser Applications in Mendenhall, Pa. “When they exposed it to laser, they tracked the mitochondria reproduction, which was higher, and they also found that they had actual neural sprouting in a large portion of the culture.”
This kind of healing, inflammation relief and pain management is something Janet Van Dyck, DVM, of the Canine Rehabilitation Institute in Wellington, Fla., sees daily. She uses her lasers in all areas of her practice, not just rehab.
“People are becoming increasingly aware of the many ways that they can put the laser to use, including using it to treat acupuncture points in the fractious dog or a cat that doesn’t want to have needling done,” she says. “We use it for ear infections, but also for the more well-recognized things like wound healing and pain management parts of practice.”
Cascade of Events
Therapeutic lasers provide pain relief and healing in a number of ways, Riegel says. When the veterinarian or technician applies the laser to the animal’s skin, photons travel to the sick or inflamed cell and stimulate it. The cell absorbs the light energy via one of its chromophores—special structures found in the cell’s mitochondria and on the cell’s membrane.
That mitochondrial stimulation produces ATP, or adenosine triphosphate, energizing the cell. “It stimulates a biochemical cascade of events that results in an increased respiratory rate within the cell,” Riegel says.
The pain relief that follows is also part of this cascade of events, he says.
“You get a release of nitric oxide, and when it’s released from the cell, its No. 1 job is vasodilation and its No. 2 job is to act as a neurotransmitter, increasing the ability of nerves to transmit an impulse by normalizing their conductivity,” Riegel says. “You also get a release of beta endorphins, which provides more analgesia.”
The lasers also release serotonin, which is why the modality appears to work well on lick granulomas, Riegel says.
“Lick granulomas are basically obsessive-compulsive disorders,” he says. “The dog sits there and licks because he’s bored or anxious. He’s self-medicating because it gives him a serotonin release. A very high percentage of the time, when you treat a lick granuloma with a laser, you’re causing the serotonin release. You’re also stimulating the tissue to heal. It is the new efficacious treatment for lick granulomas.”
The therapeutic effects of the lasers are cumulative, Riegel says.
“For instance, if I treat a sick cell, it will last X amount of time,” he says. “When I treat it again 48 hours later, it will last X+Y amount of time. The animal will get longer periods of relief, depending on his age, health and nutrition.”
The lasers stimulate the release of analgesic chemicals as well as increase the amount of blood flow to the area, speeding healing and regenerating tissue, Riegel says.
“Ground is being broken right now on regenerating nerve cells,” he says. “So when you’re talking analgesia, the laser stimulates on a lot of different levels to provide that pain relief.”
Class 1, 3B or 4?
Therapeutic lasers on the market today include the Class 1, Class 3B and Class 4. These classes essentially refer to the differences in the laser’s power, Dr. Van Dyck says, or how quickly it can deliver a certain number of joules, or units of energy, to inflamed or traumatized cells. Class 1 takes the longest amount of time; Class 4 takes the shortest.
“The class is determined by how many milliwatts of power the laser has,” she explains. “Each laser comes with its own wavelength. Wavelengths determine how deeply the laser will penetrate into the tissue.”
The set group of recognized therapeutic wavelengths runs from about 650 to 1,000 nanometers, with the higher the number giving the deeper penetration, she says. Laser companies acquire particular wavelengths after they’re no longer used in military applications.
“The laser companies end up buying patents on wavelengths,” Van Dyck says. “When the military decides it doesn’t really have a use for wavelength 608, for instance, it will release the patent for that wavelength and the therapeutic laser manufacturers pick them up.”
Besides power and wavelength, the length of time the laser is applied to the cell makes a difference, too, Riegel says.
“I can take a laser pointer from Staples and if I hold it onto the joint of your little finger, I could probably treat it, but it will take a day and a half,” Riegel says. “But a higher-powered laser will shorten your treatment time by providing more photons to saturate the target tissues.”
And that’s where class comes into play. An equine veterinarian may not have time to spend two hours treating one horse’s back using a lower-powered Class 3B laser, Riegel says. But if she uses a higher-powered model, like a Class 4, she could get it done faster.
Because much of the research on therapeutic lasers has been done using a Class 3B laser, Van Dyck says she recommends those to her veterinary students.
“The Class 3 laser is where the research has been done, and they have great efficacy and great safety, so from a teaching standpoint that’s where I want to be,” she says.
Riegel prefers the power of a Class 4, explaining, “With the evolution of the Class 4 laser with more power behind it, you’re now able to supply enough photons at the right wavelength to penetrate deeply into the target, whatever your target is, whether it’s a spine or joint or something else.
"Properly trained personnel administering in a proper way are not going to cause damage.”
As manufacturers of classes 1, 3B and 4 lasers refine their devices to offer the broadest range of therapeutic benefits, they all agree that light therapy is the wave of the future, and they’ve been making investments in their designs.
Dan Scott, president of Dan Scott Co. of Westerville, Ohio, says his company’s Class 1 lasers, which have earned FDA approval for use in osteoarthritis of the hand, can address general health issues, making them appropriate for regular use.
“We’ve got a study going on right now that shows a significant decrease in the amount of insulin a Type 2 diabetic patient needs when our laser is used over the pancreas,” he adds. “We’re going to submit those findings to the FDA.”
Dean Francis, Companion Therapy Laser national sales manager for LiteCure LLC of Newark, Del., says his company’s Class 4 980- and 808-wavelength lasers manage a range of conditions, from hip dysplasia and post-crutiate repair to superficial wounds and post-op healing.
“Science has dictated to us that the 980-wavelength of light seems to be the best working with pets, as far as penetration into the tissues in order to cause a photochemical reaction and therefore eliminate swelling, eliminate pain and promote healing,” he says. LiteCure conducts more than 50 continuing education courses a year on laser therapy.
Lane Jensen, general manager of the CAO Group Inc. in West Jordan, Utah, says his company has developed a new tip for its Class 4 laser, allowing veterinarians to perform soft-tissue surgery as well as pain-management therapy with the same device.
“While the laser is an indispensible tool in their tool bag, it might not be used enough for them to pay it back if they’re just using it on their geriatric patients,” he says, adding that the Class 4 can cost from $10,000 to $20,000. “But if they can use the same instrument for a declaw or a dental or a skin tumor, and then use it for lameness and wound treatment, all for the same investment, now they can afford to buy it.”
Richard Albright, DVM, president of K-LaserUSA in Franklin, Tenn., says his company’s Class 4 lasers come with nearly 50 presets that address a range of canine, feline and equine conditions, and the doctor can write up to 120 protocols.
“They also have a USB port on the back of the unit,” he says. “So every six to eight weeks, the doctors can download software or updates from our website. It’s a platform that grows with the doctor.”
Bill Grady, president of Grady Medical in Temecula, Calif., predicts that therapeutic lasers will become commonplace in clinics—as common as heart monitors.
“Laser therapy will probably be in every veterinarian’s office in the next decade,” he says. “It offers so much for the pet coming into the clinic. Right now it’s maybe in a fraction of the marketplace, but when you’re setting up a new veterinary clinic, you’re going to be getting a heart monitor, an electrical surgical unit, an IV pump and a laser therapy unit. It’s going to be that widespread.” <HOME>
This article first appeared in the July 2010 issue of Veterinary Practice News. Click here to become a subscriber.