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A 16 year old boy presents with sudden decrease of vision. He has been otherwise asymptomatic and even wrestling on the high school team as recently as the past few days. After viewing above, who do you call?

Wet AMD with new subretinal hemorrhage

Here we have an FA and color fundus photo of a left eye at two points in time. The earlier photos are above.

In the color photos, we see some peripapillary pigmentary changes. These are common and, like peripapillary atrophy, crescents, etc, don't amount to much clinically. The primary finding, is the new finding just temporal to the disc. Here we see a subretinal hemorrhage (note the small vessels which pass over the lesion). The FA is ideally read as a dynamic study, and while these images show just one point in time, they are instructive. In the first image, we can see slight hyperfluorescence in the region directly superotemporal to the disc. In the second image, this region is remarkable for a very bright hyperfluorescent lesion. Again, since we aren't given the dynamic series, its not easy to be exact, but what we can say is that the borders of the lesion are indistinct. There is also blocking on the perimeter due to blood. This leasion appears to be leaking, a CNVM, not a static window defect. Final word: juxtapapillary choroidal neovascular membrane.

Juxtapapillary CNVM represents a form of extrafoveal CNVM in wet AMD. Just as in all wet AMD, the CNVM occurs as a result of a disruption in Bruch's membrane which allows for abnormal growth of choroidal vessels which invade the subretinal and intraretinal space. These vessels are leaky and fragile. Leaking of fluid leads to the distortion of the neurosensory retinal architecture. Fragile vessels often break leading to hemorrhage as seen here.

Historically, CNVM has been described as either "classic" or "occult" and may have elements of both forms. Classic CNVM is seen as having distinct margins on FA, whereas occult often is patchy and shows stippled, irregular leakage of FA. Stay tuned for more examples in future image cases.

First Case of 2012

What do you see?

Progression of GA in Dry AMD

Finally returning from a long holiday break. Happy new year to everybody! Now back to business...

The previous case provides a good example of the progression of geographic atrophy (GA) in dry AMD. We see a set of color fundus photos and FA taken approximately 1.75 years apart. The discs look grossly normal with no significant cupping. There is some peripapillary atrophy, that is not out of the ordinary if seen on its own. The vessels look grossly normal. What we see in the macular region are areas of RPE atrophy which appear as areas where the choroidal details are more distinct. Notice, also, areas of hyperpigmentation along the margin of atrophic areas. As the atrophy progresses in the later set of images, the region becomes more distinct, larger, and more delineated. Note that the ideal imaging modality to evaluate GA is fundus auto-fluorescence, which would clearly demonstrate a rim of hyperfluorescent RPE surrounding black regions of atrophy (non-fluorescent, since RPE is absent).

Dry AMD may progress to an advanced form in a minority of patients. GA represents this advanced form. GA tends to occur in older patients than those with neovascular or wet AMD at the time of presentation. GA is closely associated with pigmentary changes and drusen within the macula. The development of GA is especially linked to large soft drusen. Large, confluent drusen over 125 microns are considered a risk factor for progression to GA. There is often a high degree of symmetry between fellow eyes. Peripapillary atrophy is very common in eyes with GA. The precise pathophysiologic mechanism for the progression of GA, which affects the RPE, choriocapillaris and neurosensory retina is poorly understood.

(Laud K, Mukkamala SK, Brue C, Slakter J. "The Future of Non-neovascular Age-related Macular Degeneration." Ho AC, Regillo CD (eds.) Age-related Macular Degeneration Diagnosis and Treatment, Springer Science+Business Media, LLC. 2011)