Geographic Atrophy and Visual Function

Abstract

We would like to counter the suggestion that geographic atrophy (GA) visualized with spectral domain optical coherence tomography “should correlate with loss of visual function.”1Yehoshua Z. Rosenfeld P.J. Gregori G. et al.Progression of geographic atrophy in age-related macular degeneration imaged with spectral domain optical coherence tomography.Ophthalmology. 2011; 118: 679-686Abstract Full Text Full Text PDF PubMed Scopus (178) Google Scholar Macular perimetry with the scanning laser ophthalmoscope (SLO) has elucidated the fact that loss of visual function in dry age-related macular degeneration also occurs in areas without GA, areas that appear identical to those retaining function. Drawing conclusions regarding loss of visual function based on areas of GA is a disservice to patients, particularly those with ring or foveal-sparing scotomas who experience increased functional difficulty despite unchanged GA and visual acuity. These patients are often reassured incorrectly that everything is stable, when in fact their scotomas have enlarged significantly, though invisibly to the examiner who does not have access to precise and accurate macular perimetry, as provided by the SLO. Several examples are available in Figure 1, Figure 2, Figure 3, Figure 4, Figure 5 (available at http://aaojournal.org). Figure 2Dry macular degeneration: 4-year progression.View Large Image Figure ViewerDownload Hi-res image Download (PPT)Figure 3Dry macular degeneration: 3-year progression.View Large Image Figure ViewerDownload Hi-res image Download (PPT)Figure 4Dry macular degeneration: 3-year progression.View Large Image Figure ViewerDownload Hi-res image Download (PPT)Figure 5Dry macular degeneration.View Large Image Figure ViewerDownload Hi-res image Download (PPT) Progression of Geographic Atrophy in Age-Related Macular Degeneration Imaged with Spectral Domain Optical Coherence TomographyOphthalmologyVol. 118Issue 4PreviewTo determine the area and enlargement rate (ER) of geographic atrophy (GA) in patients with age-related macular degeneration (AMD) using the spectral domain optical coherence tomography (SD-OCT) fundus image. Full-Text PDF Author replyOphthalmologyVol. 119Issue 4PreviewWe appreciate the interest in our recent publication, and we agree with Mogk et al that microperimetry may prove useful in reproducibly evaluating the extent of decreased visual function in eyes with geographic atrophy (GA). However, we disagree with them in their assessment of our intentions. We implied no disservice to age-related macular degeneration patients when we stated that GA results in an absolute scotoma from the loss of photoreceptors and retinal pigment epithelium, and this area of GA can be measured using spectral domain- optical coherence tomography (SD-OCT). Full-Text PDF