Few subspecialties in medicine tailor treatment to the needs of an individual as intently as retina. Phil Rosenfeld, MD, PhD, pioneered individualized care in neovascular age-related macular degeneration by characterizing as-needed retreatment (pro re nata), which evolved into the familiar treat-and-extend approaches we most commonly employ today.
Both of these approaches leverage what are often subtle findings related to the presence of and qualitative changes in fluid patterns on optical coherence tomography, data explicitly not accessible with ophthalmoscopic examination alone, to guide management decisions.
Recent work suggests that the retina imaging we perform so frequently holds many more biomarkers that promise to further refine our prognostic capabilities and management choices. Some of these biomarkers, such as reticular pseudodrusen, double-layer signs, intraretinal hyperreflective foci and hyporeflective foci within drusen, can be gleaned by simply applying a more nuanced qualitative review during our current workflow.
Other disease characteristics may best be appreciated using software algorithms. On page 23, Gagan Kalra, MD, and Justis Ehlers, MD, describe utilizing quantitative image analyses, including evaluation of OCT structural features and fluorescein angiographic vascular features, to better understand disease progression and response to treatment. For example, quantification of leakage patterns, microaneurysms, ischemic burden and vessel characteristics appear capable of substantively more accurately predicting the risk of diabetic retinopathy severity worsening.
Beyond guiding prognostication for local disease progression, retinal imaging has long been recognized as a plausible window into concurrent systemic disease states. It’s quite possible that routine retinal imaging may help us to identify Alzheimer’s and other neurodegenerative diseases, as well as diabetes mellitus and other vascular diseases, in preclinical stages. More practically for the clinic today, it’s worth noting that reticular pseudodrusen, discussed by Jorge Orellana-Rios, MD, and colleagues on page 18, has been associated with an increased incidence of cardiovascular disease.
Furthermore, applying retinal biomarkers to the drug-development process may meaningfully accelerate timelines. For example, using imaging and genetic biomarkers to enrich a population of patients with intermediate dry AMD could improve the feasibility of a trial aimed at assessing a novel therapeutic’s ability to impact the progression to advanced forms of AMD. On page 28, Johanna Seddon, MD, ScM, describes recent advances in our understanding of the interplay between genetics, diet and drusen size in AMD pathogenesis and progression.
Cumulatively, leveraging insights from imaging-based biomarkers appears to be bringing us closer to a key goal of individualized patient management: primary prevention of the pathologies that cause vision loss. RS