Direct Link: CME Monograph
It has been over 10 years since the introduction of anti-VEGF therapy for neovascular age related macular degeneration and the number of patients approaching legal blindness has fallen significantly as a result. Our understanding of best to manage this disease state has changed drastically. We’ve moved from a mandated treatment approach, to as needed approaches, and now to a treat and extend approach. Alongside this our education of how fluid subtypes matter in neovascular AMD has also broadened.
There are three accepted subtypes of fluid in neovascular AMD – intraretinal, subretinal, and subretinal pigment epithelial (sub-RPE). Each has differential effects on vision outcomes. For example, the persistence of intraretinal fluid has been shows to be a negative prognosticator for visual outcomes both in the CATT/IVAN, VIEW 1/2, and HARBOR Trials. Therefore we are keen to treat this subtype as aggressively as possible. With sub retinal fluid, the visual outcomes appear to be superior in those patients who persistently have it over those that do not. This was found in the HARBOR studies and most recently in the CATT/IVAN 5 year studies as well. Lastly sub-RPE fluid is still a little of a mystery. We don’t have any idea if alone it has a positive or negative correlation on final visual but when paired with IRF and SRF, it has potentially a larger negative correlation.
Why do these fluid subtypes matter? It helps us tell our patients what outcomes they hope to achieve. It also helps us personalize the approach of treatment – we are less likely to treat till dry with patients with persistent subretinal fluid but more aggressive with our intervals of treatment in those with intraretinal fluid.