Posts Tagged ‘LEDs for Medical Application’

Sealed LED Lighting Units from MHA Reduce Hospital-acquired Infection Rates

21 Sep

Sealed LED lighting units protect patients from harmful bacteria, while providing uniformly-distributed dimmable light.

MHA Lighting Ltd. (Manchester, UK) has worked with the National Health Service (NHS) Trusts in the UK to combat hospital-acquired infection rates using a new technology involving sealed lighting units.

MHA Lighting’s patented LED technology has been designed as a fully-sealed unit to stop dust, bacteria and deadly superbugs from gathering around warm light fittings.

Hospital room with sealed LED lighting units.

The long LED lifespan (estimated at 60,000 hrs or seven years) also eradicates the needs for routine bulb replacement, which stops harmful bacteria from being distributed into the atmosphere.

MHA Lighting MD Tom Harrison said, “Not only is the NHS saving money on operational cost for routine light maintenance, but our LED’s burn 20% of the energy of traditional fluorescents.

“The Carbon Reduction Commitment Carbon Tax on large organizations such as the NHS means for every tonne of carbon saved, hospitals receive £12 ($19.50). This money can be directly ploughed back into front-line patient services,” said Harrison.

Hospital lighting needs – 4000 K, dimming

The Manchester-based lighting specialist has completed numerous lighting refurbishments for the NHS as well as the private health care sector.

MHA recently completed an installation in North Devon District Hospital in Barnstaple, which is part of the North Devon Healthcare Trust (NDHT).

There MHA replaced traditional 72W fluorescent lamps with 4000 K Tilite 20W and 30W LED units in wards (see photo), corridors and reception areas.

The correlated color temperature of 4000K is the color required by the NHS to provide ideal light quality for examining patients or the cleanliness of the facilities.

Harrison described MHA’s technology, “Unlike other LED technologies, the light is not shone directly out, it is shone sideways and reflected out in a uniformly distributed manner,” he said. In this way, he added, the photometric performance of traditional lamps can be achieved while providing the energy and maintenance savings of LED technology.

MHA Lighting also developed a custom dimming solution for NDHT to allow lights to be dimmed down to 5%. It was fundamental for the Trust to create a more pleasant and healing environment where patients and staff are in control of ward lighting levels during sleeping hours, for example.

The Trust reduced its energy usage from 127,910 kWhr/yr to 33,044 kWhr/yr. Overall carbon emission reductions with the integration of dimmers have exceeded 75%.

Moses Warburton, re-development manager of NDHT, said: “NDHT already has an enviable standard on carbon reduction and this is part of our continuing commitment to reduce our carbon footprint.

Warburton added “It [the new lighting] has created a much better atmosphere for our patients and staff. Even light and less flicker is a huge improvement for those patients with sight problems.”


LEDs Play an Increasingly Vital Role in Life-science Applications

23 Mar

LED lighting technology can enhance our health, serve in rehabilitative therapy, and enable diagnosis of critical life-threatening conditions.

While LEDs are now widely recognized as emerging light sources for general illumination, it turns out that LED lighting can also enable a broad range of life-science-centric applications. A new article in a medical journal has documented that LED lighting can enhance the rehabilitation process for patients that have suffered traumatic brain injury (TBI). LED lighting can improve skin condition and perhaps even provide vital vitamin D. Moreover UV LEDs can help detect cell necrosis.

The American Academy of Dermatology (AAD) has identified a number of uses for LED lighting in skin-related therapies. “LEDs are significant biologically because they can modify the function of mitochondria within cells,” said dermatologist Murad Alam, MD, FAAD, chief of the Section of Cutaneous Surgery and Aesthetic Surgery, and associate professor of dermatology, otolaryngology, and surgery at Northwestern University, Chicago. “This can have applications for dermatology, as LEDs may be able to improve wound healing by reducing inflammation, and improve sun-damaged skin by accelerating the growth of new collagen.”

The narrow spectrum of LED lighting is important in some applications such as the treatment of acne. For example, the US Food and Drug Administration (FDA) has approved blue-light therapy in the 405-420-nm range for acne treatments.

“Although blue-light therapy is not as effective as oral antibiotics in clearing active acne, it appears to offer some degree of improvement for patients who are not good candidates for traditional acne therapies,” said Dr. Alam. “However, in-office treatments must be administered up to three times per week to be effective.” There are over-the-counter blue-light devices emerging for in-home treatments although Dr. Alam notes that they are less effective at least for now.

Medical researchers are also exploring LED-based red- and green-light therapies according to the AAD. Red light in the range of 600-950 nm can be used to treat acne, rosacea, and wrinkles. The red light works by stimulating the mitochondria in the skin that in turn cases older cells to behave like younger cells.

“When light of wavelengths in the range of 532 – 595 nm, or green to yellow, is used on the skin, it can reduce skin redness in some patients with age-related central facial redness and blood vessels, or rosacea,” said Dr. Alam. “But future research is needed to explore light therapy in this area of dermatology.”

Treating brain energy

It also appears self-administered LED-based light therapy can help patients recover from TBI. A new article published in the medical journal Photomedicine and Laser Surgery has documented improvements in two TBI patients that coincided with the light therapy.

The article “Self-administered light therapy may improve cognitive function after traumatic brain injury” may be difficult for anyone lacking a medical background to fully comprehend. But the website Medpage Today has a summary of the article on the LED light therapy that was vetted by a doctor, and that describes the findings simply.

Two patients with long-term cognitive impairments caused by TBI underwent four months of nightly treatment with LED lighting. Red, near-infrared LEDs were placed on the forehead and scalp. The patients showed improvements in cognitive ability after the treatment period. Moreover the patients regressed when the LED light therapy was discontinued – heightening the likelihood that the cognitive improvements were directly related to the LED lighting.

The primary author Margaret A. Naeser, PhD, of Boston University and her associates concluded, “Results from the two chronic TBI cases described here, along with those from previous [light therapy] studies with acute stroke patients and chronic, major depression cases, suggest that further, controlled research with this methodology is warranted. Transcranial red/near-infrared LED may be an inexpensive, noninvasive treatment, suitable for home treatments, to improve cognitive function in TBI patients, as well as to reduce symptom severity in post-traumatic stress disorder.”

Vitamin D synthesis and cytometry

The recent Strategies in Light Conference also featured a talk by Cary Eskow, the global director of Avnet Electronics’ LightSpeed business, that focused on emerging applications for ultraviolet (UV) LEDs, including several in the life-science area. According to Eskow, UV light causes the natural production of vitamin D3 in humans. So adding a UV LED in a luminaire could have direct health benefits.

Eskow also discussed the cytometry diagnosis procedure that is utilized to distinguish the natural cycle of cell death called apoptosis from cell death caused by toxins, trauma, or disease called necrosis. UV LEDs combined with fluorescent dyes administered to the patient enable fast and automated analysis that can save lives according to Eskow.

These life science applications have the potential to further expand the demand for LEDs. Even applications for UV or infrared (IR) LEDs that aren’t used in general-lighting applications create a positive synergy for LED makers. The manufacturers make those LEDs on the same fab lines used to make the blue emitters used to create white light and can increase fab utilization and ultimately lower component prices.


LED Technology Reduces Chemotherapy’s Side Effects

08 Mar

Medical researchers have developed a new technology that will help cancer patients stave off the effects of chemotherapy.

Called High Emissivity Aluminiferous Luminescent Substrate, or HEALS, it’s a chip covered with hundreds of sand-grain sized light emitting diodes, each of which emits energy equivalent to 12 times that of the sun. The lights are in a small box that is held near the patient’s head, while the light, which is in the far red and infrared part of the spectrum, shines on the skin.

The technology was originally developed by NASA for plant growth experiments on space shuttle flights. However, researchers at the Bone Marrow Transplant and Cellular Therapy Unit at the University of Alabama at Birmingham Hospital found a different use for it: reducing the side effects of chemotherapy and radiation treatment in bone marrow and stem cell transplant patients.

The researchers conducted a two-year clinical trial where they treated cancer patients undergoing bone marrow or stem cell transplants with the HEALS device. HEALS was used to treat oral mucositis — a common and painful side effect of chemotherapy and radiation treatment.

“Using this technology as a healing agent was phenomenal,” said Dr. Donna Salzman, clinical trial principal investigator and director of clinical services and education at the Bone Marrow Transplant and Cellular Therapy Unit, in a statement. “The HEALS device was well tolerated with no adverse affects to our bone marrow and stem cell transplant patients.”

The researchers deducted that there was a 96 percent chance the improvement in pain of those in the high-risk patient group came from the HEALS treatment.

Along with its effectiveness, the researchers say it’s cost-effective. The HEALS device itself is less expensive than a day at the hospital and a proactive therapy for symptoms of mucositis, which itself has side effects. Further, the HEALS device could lead to better nutrition since eating on chemotherapy treatment can be difficult with painful mouth and throat sores. It also may mean less narcotic use to treat mouth and throat pain and an increase in patient morale.

The HEALS device is also known as the WARP 75 light delivery system because it lets LED chips function at their maximum irradiancy without emitting heat. It was originally developed by a Barneveld, Wis., company called Quantum Devices Inc., to develop Astroculture 3. Astroculture 3 was a plant growth chamber on the space shuttle that used infrared HEALS technology. Quantum adapted the HEALS technology for medical use.

“Quantum Devices and its medical partners have been able to take a space technology and adapt it for an entirely different application to significantly help people here on Earth,” said Glenn Ignatius, president of Quantum Devices, in a statement.


Flexible LED Arrays Target Biomedical Applications

08 Jan

University of Illinois research yields flexible arrays of LEDs that could be used as medical implants, but that might find other more near-term practical applications.

Both the trade and popular press have hyped the story coming out of the University of Illinois about flexible LED arrays that might be implanted in the body in various medical applications. The more interesting aspect, however, may be the manufacturing technique and how it might be applied to other applications. Indeed, the technique can deposit arrays on a variety of flexible materials ranging from aluminum foil to rubber to paper, and can support waterproof deployment.

The media has focused on the medical application because that is a potentially exciting idea and the research led by John Rogers was focused on that area. Scientific American has among the best accounts of the stretchable LED sheets developed by Rogers and his colleagues detailing applications such as photoactivated drug delivery.

The medical application, however, could be five or even ten years down the road. Moreover, it’s likely that implantable technologies remain the last choice in terms of how to solve a medical problem due to the cost of developing the technology and the potential risk involved.

The manufacturing technique developed by Rogers and his team, however, is quite ingenious and potentially useful in other applications. Indeed the researchers even wrapped a string of the LEDs around a thread.

LEDs are typically manufactured on a substrate such as a rigid semiconductor wafer. The University of Illinois team follows that typical path to create an array of LEDs on a wafer. The team then dissolves the top layer of the substrate freeing a planar stretchable LED array that can be transferred to other flexible substrates. For instance, the array can be encased in plastic or rubber for implantation in the body – or perhaps for underwater uses.

The manufacturing technique yields LEDs that measure 100 microns (micro meters) wide and only 2.4 microns thick. The conductive strands that connect LEDs in an array can be stretched or twisted.

Until now, organic LED (OLED) technology has been the primary option for applications requiring planar light sources with flexible properties. The new LED technology may or may not compete with OLEDs, but the latter still faces manufacturing issues that have gated volume production.


LED Device Could Advance Photodynamic Therapy for Skin Cancer

12 Nov

Scientists at UC Irvine are exploring new ways to image cancerous lesions using LEDs that might enhance photodynamic therapy (PDT) treatments for cancer.

Can skin cancer be treated with light? Scientists at the University of California, Irvine (UC Irvine) believe so. They’re exploring new ways to image cancerous lesions using LEDs that might advance a light-based technique for treating cancer called photodynamic therapy (PDT), according to an article on the OptoIQ website.

The work will be described at the Optical Society’s (OSA) 94th annual meeting, Frontiers in Optics (FiO) 2010 at the Rochester Riverside Convention Center in Rochester, NY from October 24-28.

In PDT, photosensitizing chemicals that absorb light are injected into a tumor, which is then exposed to light. The chemicals generate oxygen radicals from the light energy, destroying the cancer cells. PDT is currently approved by the U.S. Food and Drug Administration (FDA) for the treatment of esophageal and lung cancer.

Rolf Saager, who works in the lab of Anthony Durkin at the Beckman Laser Institute at UC Irvine in collaboration with Kristen Kelly, M.D., and Modulated Imaging, believes that PDT could also be used to treat skin cancer. But one obstacle to this application is the lack of a detailed imaging technique to target and monitor the effectiveness of PDT.

Exploiting a technique known as spatial frequency domain imaging, the team has designed a new device with an array of five different colors of LEDs that illuminates skin with distinct intensity patterns. These patterns can change depending on the structure of the tissue and the pigments in the skin. With appropriate models of light propagation, the resulting images reveal the biochemistry of the tissue. “Through this imaging modality, it is now possible to assess how the therapeutic light will travel throughout the affected tissue, quantify the drug present within the lesion and monitor its efficacy during treatment,” says Saager.

To evaluate this spatial frequency domain imaging system, the scientists imaged a small population of skin cancers prior to treatment to characterize the variability among subjects and within the lesions themselves. The process took 5-10 seconds and produced images with a resolution of 30 microns, revealing spatially resolved maps of the optical properties of the lesions, tissue oxygenation and quantitative distribution of the photosensitizing drug.

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