Taking out the Waste – AMD is a Disease of Accumulated Debris but May be it is Time to Spring Clean

Prof Robyn Guymer AM, : Dr Grant Raymond

Meeting:  2018 RANZCO


Date:      -

Session Title: Lecture- Norman McAlister Gregg

Session Time:      -

Synopsis: Age-related macular degeneration (AMD) is a multifactorial disease and is a leading cause of vision loss in our elderly communities. The initiating pathogenic mechanisms that lead to loss of vision are not completely understood, yet early disease is characterized by the deposi- tion of debris, where the accumulation of by-products exceeds the normal clearance capacity of the retina. Understanding the underlying mechanisms by which debris accumulates in AMD is critical for understanding disease pathways and ultimately developing novel treatment targets for early AMD. We have been investigating a novel hypothesis for the pathogenesis of AMD where we argue that a functional deficit in immune cell phagocytosis is a major contributor to the accumulated debris, triggering events that lead to irreversible damage and vision loss. We have also been investigating, in both animal and human studies, the possibility that subthresh- old nanosecond laser, specifically using the retinal rejuvenation therapy (2RT) laser, designed and manufactured in Australia, might trigger a series of events that could lead to reduced debris accumulation. Finally, we have defined early features, as seen on optical coherence tomography (OCT), that signify the earliest point where there is loss of RPE and photoreceptors in AMD. These signs, that define a stage called, nascent geographic atrophy (nGA), provide a biomarker that can be used as an early disease endpoint, enabling earlier stage intervention studies in AMD. Using a combined atrophic endpoint, incorporating these early signs of atrophy, we were able to conduct the world first randomized trial of 2RT laser in intermediate AMD to determine its safety and efficacy in slower progression of vision threatening late stage AMD. In the 2018 Norman McAlister Gregg lecture I will discuss this research which furthers our understanding of AMD.