A person diagnosed with the 'dry' form of late-stage age-related macular degeneration (AMD) today has limited options.
While injections are able to stop the growth of abnormal blood vessels in 'wet' AMD, eyecare professionals focus on managing the dry form disease through lifestyle changes and regular check-ups.
That may soon change, with two treatments aimed at slowing the progress of dry AMD approved for use in the U.S. in 2023 - one having been trialled at CERA.
CERA Deputy Director and Head of Macular Research Professor Robyn Guymer AM says these treatments may be available in Australia in the near future - with more to potentially follow.
"While these treatments can't restore vision, they try to slow the progress of the disease," she says.
It's hoped these treatments will be the first step towards transforming the way dry AMD is managed - much like sight-saving treatments have for 'wet' AMD.
Future referral pathways
There are two different forms of late-stage AMD: wet and dry.
Both result the death of cells in the macular and the loss of central vision, but in wet AMD damage is caused by abnormal blood vessels that grow under the retina and bleed.
Eye injections can prevent these blood vessels from growing, but this treatment does not work for dry AMD.
Professor Guymer says with the prospect of potential treatments options, people diagnosed with the early stages of dry AMD in the future will have a very different experience to those diagnosed today.
"Our hope is that optometrists will see people with the beginnings of dry AMD and refer them to an ophthalmologist for counselling around potential treatment options," she says.
With advanced imaging such as OCT scans, ophthalmologists will also have access to more information about how a person's dry AMD is progressing.
"Ophthalmologists need that information to determine how fast the disease is progressing, helping to determine whether treatment could start now or to check back in another year," says Professor Guymer.
"It will depend on how fast the disease is progressing, because some people are fast paced and some are slow growers, and this will play into decisions around treatment."
Not all treatments will be the right option for everyone, and Professor Guymer says it will be important to discuss the risks and benefits.
"In addition to their vision, doctors will need to take a holistic look at the patient's individual needs, taking into account factors such as age and visual needs like driving."
Should treatment go ahead, Professor Guymer says it will then be crucial to determine whether or not it is working by monitoring the disease's progress every six months to a year.
Preparing for a new era
When new treatments arrive, it will also be vital that clinicians can accurately distinguish AMD from similar yet genetically different inherited retinal diseases (IRDs).
CERA Honorary Research Fellow Dr Ceecee Britten-Jones is working to improve diagnosis and enable differentiation between AMD and IRDs, so people get the right diagnosis and treatment.
It will also be important that clinicians can identify people with dry AMD who are most at risk of progressing to vision loss more rapidly.
CERA's Ophthalmic Neuroscience team are using their hyperspectral camera to scan the eyes of people with dry AMD - using AI that aims to predict where the disease may progress next.
These projects are collaborations with the Macular Research Unit's natural history of AMD research.
While the prospect of slowing the progress of dry AMD is exciting, the Macular Research Unit's ultimate aim is to find ways of treating the disease before vision is threatened.
"Currents treatments are focused on the sight-threatening stage of dry AMD," says Professor Guymer.
"Whereas, our natural history studies are trying to better understand how you would start treating people before they have any vision loss."
Professor Guymer has seen AMD transform from a disease with few treatments, to one where many people can manage their condition.
"The prospect that soon many more people will have better options to protect their vision is very exciting."
Our goal is to advance scientific understanding of macular diseases, in particular age-related macular degeneration - and ultimately develop new treatments to prevent vision loss.
Spotting the differences between macular diseases isn't always easy - finding new ways to do so will have a big impact.
