Age-Related Macular Degeneration
Age-Related Macular Degeneration (AMD) is a chronic eye disease that can result in blurred vision and/or a loss of central vision. In its early stages, AMD is characterized by the presence of waste deposits under the macula, known as drusen, and by pigmentary abnormalities such as light or dark spots in the macula. Patients suffering from AMD often exhibit a thickening Bruch’s membrane.
When AMD occurs it is typically categorized into either the dry or wet form of the disease. Presently, if a patient is diagnosed with early AMD they are told that nothing can be done until the disease reaches its late stages, by which time most patients have suffered irreversible vision loss.
Wet AMD, which is the more aggressive, late-stage of the disease, can be treated with intraocular injections of anti-vascular endothelial growth factor (anti-VEGF) medications. Vitamins (AREDS formulation) are also often prescribed to patients with AMD.
Unlike anti-VEGF treatment, however, 2RT™ offers the potential to intervene much earlier in the disease process and thereby eliminate or delay the risk of vision-threatening complications associated with patients whom have early AMD.
AMD: How Does 2RT Work?
As the eye ages, the permeability of Bruch’s membrane is reduced, inhibiting its ability to remove and exchange fluid and waste deposits. Current estimates suggest that by age 40 the flow is reduced to approximately 50% of what it is in infants. By age 80, it is reduced to a small fraction. Reduced fluid outflow across Bruch’s membrane has been shown to play a central role in the development of retinal pathologies, contributing to retinal edema and in some cases accounting for accumulation of debris which result in the formation of drusen. In addition, reduced nutrition and oxygen may promote neovascularisation by stressing retinal cells to the point that they secrete endothelial growth factors and other enzymes that are part of the body’s wound healing process.
Targeted at the RPE and Bruch’s membrane, 2RT™ stimulates a biological healing response in the eye which improves permeability of Bruch’s membrane and thereby restores the transport of fluid across Bruch’s membrane. By restoring metabolite flow to retinal cells, 2RT™ may also reduce the cell production of endothelial growth factors and other precursors of neovascularisation.
Note: 2RT™ has a CE Mark (Conformité Européenne) for treatment in patients with early Age-Related Macular Degeneration (AMD) where it can produce bilateral improvements in macular appearance and function
FIGURE 2: Wound Healing Effect of 2RT
Research conducted by Professor Erica L. Fletcher MScOptom, PhD (Department of Anatomy and Neuroscience, The University of Melbourne, Australia) and colleagues has shown that the integrity of the (human) RPE remains intact following treatment with 2RT®. (5)
Pre-treatment. The normal human RPE morphology has a polygonal appearance.
One week following treatment with 2RT®, the presence of larger RPE cells were noted at the injury border of the lasered area, with some cells extending into the lesion site.
One month following treatment with 2RT® the RPE layer was intact; the lesion site was completely covered with enlarged cells.
Source: Images courtesy of Professor Erica L. Fletcher MScOptom, PhD
Note: 2RT® has a CE Mark (Conformité Européenne) for treatment in patients with early AMD where it can produce bilateral improvements in macular appearance and function.
Ferris L.F. et al Ophthalmology 120:844-851 (2013)
Ferris L.F. et al Arch of Ophthalmology 123(11): 1570-4 (2005)
J.J.Zhang, Y. Sun, A.A. Hussain and J. Marshall. Laser mediated activation of human retinal pigment epithelial (RPE) cells and concomitant release of matrix metalloproteinases (MMPs). Invest. Ophthalmol. Vis. Sci. May 17, 2012 vol 53 no. 6 2928-2332.
Jobling et al., “Nanosecond Laser Therapy Reverses Pathologic and Molecular Changes in Age-Related Macular Degeneration without Retinal Damage,” The FASEB Journal 29, no. 2 (February 1, 2015): 696–710, doi:10.1096/fj.14-262444.
A. I. Jobling et al., “Nanosecond Laser Therapy Reverses Pathologic and Molecular Changes in Age-Related Macular Degeneration without Retinal Damage,” The FASEB Journal 29, no. 2 (February 1, 2015): 696–710, doi:10.1096/fj.14-262444.