This site is intended for UK healthcare professionals.
menu
close
menu
close

Identifying Geographic Atrophy (GA)

The time is now

GA Causes Irreversible Vision Loss1,2

GA, an advanced form of dry age-related macular degeneration (AMD), is defined by the presence of sharply demarcated atrophic lesions of the retinal pigment epithelium (RPE) and outer retina.3,4

vision-loss-desktop
vision-loss image-mobile

Images courtesy of Dr. Mohammad Rafieetary (“Early AMD” and “Geographic Atrophy”), Dr. David Lally (“Intermediate AMD”), and Dr. Mark Dunbar (“Neovascular AMD”). Images are from separate patients.

Drusen Are a Hallmark of Early Disease

Drusen are a hallmark of early AMD, which can be observed by direct examination of color fundus photography (CFP) or optical coherence tomography (OCT).1,2,5,6 Drusen come in various sizes. The larger the drusen, the greater the chance of progression to an advanced form of AMD such as GA.1,2

Early AMD with drusen (white arrows). Pigmentary abnormalities are absent. Drusen are found between the RPE basement membrane and Bruch’s membrane.3

Degenerative Changes Occur in Intermediate Disease

Intermediate AMD is associated with extensive intermediate drusen (63-124 µm) or more than 1 large druse (≥125 µm).3 Pigmentary changes are also indicative of intermediate disease. Degenerative changes in the retinal layers may also be observed.3,4

Changes in visual function can occur before declines in visual acuity.7 Patients should be instructed to inform you of any sudden and/or persistent change in vision such as blurriness or distortion.8,9

See how disease progression impacts functional vision in the video here.

A

Intermediate Disease-1

B

Intermediate Disease-2

Immediate drusen (white arrows) can be visualised clearly on (A) OCT and (B) CFP.5,10 Pigmentary changes (wedges) visualisation on CFP may precede atrophic changes.4,11 Images are from separate patients.

Lesion Areas Enlarge in GA

Dry AMD progression to GA is characterised by the development of new atrophic lesions, growth of individual areas, or coalescence of multiple lesions. GA can be detected using various imaging modalities, such as OCT, which are commonly available in most clinics.1-3,12

A

lesion-areas-1

B

lesion-areas-2

C

lesion-areas-3

GA can be detected with most available imaging modalities. Atrophic lesions represent a loss of the RPE, overlying photoreceptors, and underlying choriocapillaris.2,3 Atrophic regions (white arrows) are represented on (A) CFP, (B) OCT, and (C) fundus autofluorescence imaging (FAF). Images are from separate patients.

Monitoring for Progression Is Critical

Lesion patterns can be predictive of slower or faster progressing disease and provide key data to inform management strategies.2,3 Patients can present with a wide range of visual symptoms; therefore, it is critical to monitor patients for disease progression.4,7

Lesion Size

Slower Progression

Small Baseline Lesions

Faster Progression

Large Baseline Lesions

Location

Slower Progression

Foveal

Faster Progression

Non-foveal

Focality

Slower Progression

Unifocal

Faster Progression

Multifocal

Lesion size, location, and focality may be predictive of the rate of lesion progression in GA. Smaller baseline lesions progress more slowly than larger baseline lesions. Foveal lesions progress more slowly than non-foveal lesions. Unifocal lesions progress more slowly than multifocal lesions.2,3

Watch and Discover: Disease Progression

See how GA progresses over time and how it may affect a patient’s vision, daily activities, and independence.

References

  1. Holz FG, Schmitz-Valckenberg S, Fleckenstein M. Recent developments in the treatment of age-related macular degeneration. J Clin Invest. 2014;124(4):1430-1438.
  2. Boyer DS, Schmidt-Erfurth U, van Lookeren Campagne M, Henry EC, Brittain C. The pathophysiology of geographic atrophy secondary to age-related macular degeneration and the complement pathway as a therapeutic target. Retina. 2017;37(5):819-835.
  3. Fleckenstein M, Mitchell P, Freund KB, et al. The progression of geographic atrophy secondary to age-related macular degeneration. Ophthalmology. 2018;125(3):369-390.    
  4. Sadda SR, Chakravarthy U, Birch DG, Staurenghi G, Henry EC, Brittain C. Clinical endpoints for the study of geographic atrophy secondary to age-related macular degeneration. Retina. 2016;36(10):1806-1822.
  5. Mones J, Garcia M, Biarnes M, Lakkaraju A, Ferraro L. Drusen ooze: a novel hypothesis in geographic atrophy. Ophthalmol Retina. 2017;1(6):461-473.
  6. Ambati J, Ambati BK, Yoo SH, Ianchulev S, Adamis AP. Age-related macular degeneration: etiology, pathogenesis, and therapeutic strategies. Surv Ophthalmol. 2003;48(3):257-293.
  7. Sunness JS, Rubin GS, Applegate CA, et al. Visual function abnormalities and prognosis in eyes with age-related geographic atrophy of the macula and good visual acuity. Ophthalmology. 1997;104(10):1677-1691.
  8. Flaxel CJ, Adelman RA, Bailey ST, et al. Age-Related Macular Degeneration Preferred Practice Pattern®. Ophthalmology. 2020;127(1):P1-P65.
  9. Jaffe GJ, Khanani AM. Two studies to learn if avacincaptad pegol works and is safe in people with geographic atrophy: a plain language summary of the GATHER1 and GATHER 2 studies. Immunotherapy. 2024;16(4):205-221.
  10. Sadda SR, Guymer R, Holz FG, et al. Consensus definition for atrophy associated with age-related macular degeneration on OCT: classification of atrophy report 3. Ophthalmology. 2018;125(4):537-548.
  11. Garrity ST, Sarraf D, Freund KB, Sadda SR. Multimodal imaging of nonneovascular age-related macular degeneration. Invest Ophthalmol Vis Sci. 2018;59(4):AMD48-AMD64.
  12. Lindblad AS, Lloyd PC, Clemons TE, et al. Change in area of geographic atrophy in the Age-Related Eye Disease Study: AREDS report number 26. Arch Ophthalmol. 2009;127(9):1168-1174.