Retina Today - 2013 Macula Society Musings (May/June 2013)

摘要

Editora??s note: This blog was posted on April 24, 2013, to www.eyetube.net. Occasionally, we will be featuring content from our bloggers for retina in Retina Today. Nikolas London, MD, contributed the following, which details his experience at the 2013 Macula Society meeting. In late February of this year, I was lucky enough to ride the coattails of Paul Tornambe, MD, to the Macula Society meeting in Dana Point, CA. For my first blog entry for Retina Today, I provide a summary. Advanced Imaging Modalities For me, retinal imaging is beautiful and one of the most rewarding parts of the retina subspecialty. I am still excited by the array of modalities to evaluate the function and anatomy of the retina, and I particularly enjoy using these images to show my patients exactly what is happening to them and why, as well as how they are responding to treatment. Despite huge advances over the past decade, the envelope is still being pushed, and I pay particular attention to such talks at ophthalmology conferences. Richard Rosen, MD (New York Eye and Ear Institute), presented a novel technique called fluoro-microangiography, which is fluorescein angiography (FA) using an adaptive optics scanning laser ophthalmoscope (AO SLO). FA has been the gold standard for decades for evaluating the retinal vasculature and integrity of the blood-retinal barrier. AO SLO enables a much higher resolution assessment of the living retina at a cellular level. Dr. Rosen presented examples showing ultrastructural features of microaneurysms, beautiful images from normal subjects, as well as extended widefield imaging of the retinal periphery. Mark Pennesi, MD (Oregon Health and Science University), presented retinal imaging using flood-illuminated AO, which provided unprecedented resolution and detail of retinal structures, including the ability to calculate the density of cones in the perifoveal retina (ranges from 1300 to 1700 cones/degree2 in normal subjects). He illustrated how perifoveal cone density decreases slightly with age and drastically in diseases such as retinitis pigmentosa or Stargardt disease. These advances make the retina field particularly exciting for those of us dazzled by technology and hold the promise of improving our ability to care for our patients. Using less novel technology (but with no less interesting results), other talks focused on enhanced understanding of subtle symptoms of early age-related macular degeneration (AMD). Catherine Cukras, MD (National Eye Institute), presented data showing deficits in rod-mediated dark adaptation in non-advanced AMD. Moreover, Karl Csaky, MD (Texas Retina Associates), presented electroretinogram data demonstrating a progressive loss of rod sensitivity with advancing AMD. These studies provide some confirmation of patientsa?? subjective difficulties with dark adaptation. AMD Genetics The genetics of macular degeneration is a particularly hot field, holding promise to better define the risk for AMD progression and to illustrate potential therapeutic targets in the complicated cascade of events that contribute to advanced AMD. Numerous disease-associated single-nucleotide polymorphisms (SNPs) have been identified, including protective and detrimental markers. These include ARMS2, CHF, C2, C3, H3, and CFB. Nancy Holekamp, MD (Pepose Vision Institute), presented a comparison of 2 commercially available genetic tests for AMD, Sequenoma??s RetnaGene and Arctica??s Macula Risk. She found that they were discordant 60% of the time, with RetnaGene typically predicting the higher risk. On subsequent analysis, she noted that Macula Risk did not identify a moderate risk allele and appeared to misidentify it as a protective allele. It is important to note that this study was done on first-generation tests, while both companies have gone on to develop improved tests. In practice these tests can play a role in certain cir