By Joy LePree, Technical Editor
www.pddnet.com
Almost everyone has seen an episode of Star Trek where the ship's doctor uses a hand-held laser device to heal any and all injuries crew members may have sustained while exploring new worlds. While this seems far-fetched to those of us who are used to receiving more traditional medicines to heal our aches and pains, the truth is light therapy is becoming a reality.
Cutting-edge companies are working with partners in the medical research industry, as well as NASA and the Defense Advanced Research Project Agency (DARPA), to provide therapeutic light-emitting diode (LED) devices that may assist in the treatment of anything from wounds to muscle aches to torn ligaments to acne to blindness and more serious illnesses.
Currently a handful of tech companies are making medical LED devices for professional medical use, as well as lower-tech versions for over-the-counter consumer use. While each company's technology differs, they all work on the same basic premise: many illnesses are caused by cells inside the body being starved for energy. Injuries are often slow to heal for the same reason, so if a way can be found to provide the correct wavelength of light (which provides an alternate form of energy) and have it absorbed by those starved cells, it should speed the healing process.
"If the cells are starved for energy, you have to find a way to provide them with the energy they need to recover from injury or disease," says Dr. Harry T. Whelan, professor of neurology at the Medical College of Wisconsin in Milwaukee, who is conducting studies using medical LEDs developed by Quantum Devices Inc. "Using LED therapy, the energy that we provide to those cells is in the form of near-infrared light, and the wavelength we've used most often is 670 nanometers, but we are still studying different wavelengths to find the optimum for different clinical situations. And currently, we use about 50 milliwatts per square centimeter of power intensity for a period of about one to three minutes to generate anywhere between four and eight joules per square centimeter of full energy. The energy is then converted by the cells into a high-energy phosphate, which helps speed the healing."
Some LED devices developed by companies other than Quantum operate at significantly lower wavelengths and power intensities.
While there's an array of devices out there, from knee wraps to hand-held instruments to entire LED beds, they are all composed of several basic components. First there are the LEDs, which aren't typical LEDs. "The LEDs we use are much more powerful than the ones you have in your computer," says Ron Ignatius, founder and chairman of the board of Quantum Devices in Barneveld, WI. "They are 10 times as bright as the sun, but only offer helpful wavelengths without the harmful ones."
Depending on whether the device is a hand-held, a wrap, or a pad, the LEDs are placed on a circuit board or a pad, says Randall Everett, president of Diomedics, a Melrose, FL-based developer of the technology. The devices are either battery- or ac-powered, which is usually preferable. "With batteries, you have constant power for only about an hour and then it starts dropping off and you lose the effectiveness of the treatment," says Everett.
When designing medical LEDs, experts say that subtle differences in engineering technology don't result in significant differences in the basic biology of how and why LED therapy works. What's more important than the arrangement of lights or the housing is finding a way to get the appropriate intensity of light and power to penetrate the affected cells. "It's basically different ways of arranging the LEDs to get a certain intensity of a certain wavelength into tissue long enough to activate the energy chemistry of the cells so that the cells have more energy in the form of light and they can channel that energy into running the cells normally," says Whelan.
The key to providing the appropriate wavelength and power is cooling technology, says Ignatius, because it allows the LEDs to supply light without heat. "It is necessary to provide built-in cooling technology to dissipate the heat so you can use the LED therapy, which penetrates very deeply, but still touch the lights to the skin without causing discomfort or burns," he says. The cooling technology used by different manufacturers is usually proprietary and covered by patents.
Quantum's devices are considered to be extremely sophisticated because of their higher wavelengths, power intensities, and cooling technology. Because of its expertise in this area, Quantum has been working with NASA and DARPA to develop devices that would be useful in space and on the battlefield.
Initially, Quantum began working with NASA to create something that would help stimulate plant growth in space. "I suggested the use of LEDs and they almost laughed me out of the room," recalls Ignatius. "But someone did a little research and found that the idea wasn't all that far-fetched and that it really worked."
Since NASA found that LEDs could be used to provide energy for plant cells to grow, it wasn't that much of a leap to relate the technology to human cells, says Whelan. Subsequently, NASA provided funding to Quantum Devices with the hopes that it could develop a device for astronauts to stem the loss of bone and muscle mass, which occurs during long periods of weightlessness. Studies are being conducted to see if this therapy will work.
Meanwhile, Whelan and engineers at Quantum discovered a more down-to-earth use for this technology in the form of a product called the Spectralight. "We are currently using it to treat patients with a condition called mucousitis, which occurs as a side effect of cancer treatments," says Ignatius.
Mucousitis occurs when the mucous membranes of the body, especially those in the mouth, break down and cause bleeding and ulcers that lead to the inability to eat, making recovery more difficult. "Dr. Whelan found that by exposing just one cheek two minutes a day to the light source it could start eliminating the condition, and later we found that by exposing patients to the light source before the problem even started, it could be prevented," says Ignatius.
Following the success of the Spectralight, Quantum received funding from DARPA to develop a device that soldiers could carry into combat to self-treat muscle aches and wounds with little or no training. In response, Quantum created the Warp 10, which is a battery-powered, hand-held infrared device. Currently, a handful of special operations forces are trying the Warp 10 on an experimental basis.
The military is also looking into whether this same device could be used to treat blindness caused by enemy troops using laser weapons. Studies on reversing blindness in rats have shown promise in this area.
Although Quantum's products are ultra high-tech devices for use only by professionals or the military, other companies offer over-the-counter LED devices that have been approved by the FDA for treatment of muscle aches and pain.
"The FDA has cleared a number of applications for consumer use, so people can buy them without a prescription," says Richard Braden, president of BioScan, a Palitas, NM-based developer of medical LED therapies. "What used to be just in the realm of the laser surgeon or dermatologist is now available to people because the devices are being powered in such a way that they are completely safe."
BioScan currently has three devices approved by the FDA for consumer use for the treatment of muscle aches and pain. One is a light patch, which is a 5-inch-by-8-inch oval pad with all the LEDs contained within it. The patch is placed on the sore area. Another is a spinal pad designed to contour with the spine. It includes lights placed along the areas that cover the nerve endings that are most responsive to LED energy. The company also has a battery-powered knee wrap, which is a knee brace with light devices built into it so that the user can put it on, turn it on, and walk around while receiving therapy.
Diomedics makes similar products as well as a bed with more than 2,000 LEDs on it. "It looks like a tanning bed and has a box attached that controls the lights," says Everett. "The patient lays on it and it treats the whole body for pain and muscle relaxation at one time."
Much research is underway on the use of medical LED therapy to determine whether there are other applications for light therapy. "Research is currently being done on the different effects of different spectrums of light on living tissues," says Braden. It is thought that the visible red spectrum, which is roughly in the 600 to 700 nanometer range, is effective with surface issues such as wound care and that higher wavelengths, including infrared, are more penetrating. Studies also suggest that going down to the 400 or 500 nanometer spectrum, which is blue light, might be effective for treating skin disorders including acne and scarring.
"Companies in this business are looking at the medical research that is being conducted regarding different frequencies of light to see where this technology might take us," says Braden. He foresees wound care as being the next big application. "You can expect over the next few years to see LED therapy as being the primary treatment for wounds such as post-surgical and non-healing wounds like diabetic ulcers."
Whelan and Ignatius say they would like to test their technology in other clinical situations such as spinal cord injuries and for treatment of Parkinson's disease, strokes, brain tumors, and tissue and organ regeneration.
"It may seem strange to some people because it is very much a change in the whole paradigm of medicine, which has been pretty much poisons and knives up until this point. The use of natural energy at an intensity that is brighter than the sun, but still nonetheless near infrared light at wavelengths that are helpful and not harmful, to enhance the cells' natural biochemistry truly has a lot of potential in the medical arena," says Whelan.