Take-home message: Treatment with red light technology resulted in a significant improvement in the tear break-up time in the vast majority of patients. This may be a future light treatment for the improvement of dry eye disease in patients with meibomian gland dysfunction.
By Lynda Charters; Reviewed by Rolando Toyos, MD
Memphis, TN —
Red light technology (RLT) may be a future treatment to improve dry eye disease in patients with meibomian gland dysfunction. Application of RLT therapy resulted in improvement in the tear film break-up time in more than 90% of patients with dry eye disease. The results are similar to those reported previously in patients treated with intense pulsed light (IPL) treatment.
(Figure 1) Alan G. Kabat, OD, FAAO, performs microblepharoexfoliation on a patient with ocular surface disease using the handheld device. (Photos courtesy of Alan G. Kabat, OD, FAAO)Various light treatment technologies have been used successfully before in other areas of medicine such as dermatology.
Beginning in 2002, Rolando Toyos, MD, and colleagues noticed that in some of their patients in their Memphis, TN, practice who had undergone application of IPL treatment to skin near the meibomian glands, the function of the glands and their dry eye disease improved.
This prompted the investigators to later conduct a 3-year retrospective study of IPL treatment of dry eye disease in 91 patients. The therapy consisted of IPL application and gland expression during monthly visits. The results indicated that 87% of patients had improved tear break-up times after seven visits and four maintenance visits; 93% of patients expressed satisfaction with the improved dry eye disease.
A caveat regarding IPL therapy is that only doctors trained in its application should administer the treatment and special eye shields are needed to avoid ocular damage. The investigators published their findings in the Photomedicine and Laser Surgery
Low light-emitting diode RLT therapy using visible light, which was discovered by the National Aeronautics and Space Administration, uses infrared light and, according to Dr. Toyos, also is used for facial rejuvenation. When applied to skin, RLT increases fibroblast activity by increasing the cellular adenosine triphosphate (ATP) activity, which increases elastin and collagen production, he explained. These effects have been documented in numerous studies.
(Figure 2) Chronic dry eye symptoms include inflammation of the eyeild margins and inspissation of the meibomian glands. These observations raised the question about whether RLT can be used to treat meibomian gland dysfunction. The investigators theorized that RLT therapy applied close to the eyelid should result in increased cellular ATP activity in the cells of the meibomian gland, including improving the meibomian gland function. In contrast to IPL therapy, RLT is a low-light therapy, and patients can apply the treatment at home.
When using RLT therapy, Dr. Toyos explained that 600 to 650 nm of visible light is applied to the periorbital skin using a light-emitting diode, generating up to 6 joules/cm.2 The application is done using The Q Device (Quantum Ocular Biosciences) for at least 3 minutes at least twice weekly.
Prospective clinical trial
(Figure 3) A patient with severe blepharitis before (A) and after (B) a single microblepharoexfoliation treatment.Dr. Toyos and colleagues then conducted a prospective study of 52 patients to determine the effectiveness of RLT for treating evaporative dry eye disease due to meibomian gland dysfunction. The investigators measured the tear break-up time before and after RLT treatment with wavelengths of light between 600 and 650 nm.
All study patients had dry eye symptoms that included ocular burning, grittiness, and sandiness and a tear break-up time of less than 10 seconds. All patients had clinically observable meibomian gland dysfunction.
Patients administered the treatment at home. They were instructed to place the device that administered the RLT over closed eyes for 3 minutes on each eye at least twice a week but not more than once daily. The patients were treated for 3 months.
The investigators obtained tear break-up time data before and after treatment for 81 eyes. Dr. Toyos reported that the mean break-up time before treatment was 3.62 ± 2.05 seconds (range, 0.9 to 8.54 seconds). After treatment, the mean break-up time was 5.87 ± 2.95 seconds (range, 1.5 to 16.19 seconds). The difference between before and after treatment reached significance (P<0.001).
There was no significant difference between the 41 right eyes and the 40 left eyes before and after treatment.
“Over 90% of patients reported improvement in their dry eye symptoms,” he stated.
Dr. Toyos concluded that on average, treatment with RLT results in a significant improvement in the tear break-up time. This may be a future light treatment for the improvement of dry eye disease.”
Since the completion of the clinical study under discussion, the investigators have been conducting studies of other wavelengths of visible light including infrared light. They expect to announce their results shortly.
Rolando Toyos, MD
E: [email protected]
Dr. Toyos is a consultant for DermaMed Solutions and Quantum Ocular Biosciences.