Geographic atrophy (GA) is the terminal stage of nonexudative age-related macular degeneration and results in central vision loss when atrophic lesions extend into the fovea. GA can cause irreversible damage to the fovea in as few as 2.5 years.

Although new agents like pegcetacoplan and avacincaptad pegol slow GA progression, their utility in the clinic is limited for several reasons: these agents slow lesion growth but as yet do not have demonstrated visual acuity improvement; they require frequent intravitreal administration; can have severe side effects; have a higher rate of conversion to neovascular macular degeneration; and are costly.

The Atrophy Advisor Calculator is written in JavaScript code. It takes inputs of the clinician’s estimate of distance of the closest point of GA to the fovea, and the patient’s age and sex to produce outputs of estimated time until the GA touches the fovea and the patient’s expected lifespan.

This calculator is designed for use by eyecare professionals to help them manage their patients with Geographic Atrophy. 

Simply enter the patient’s age, sex, and current GA distance from the fovea.  If you have calculated a personalized rate of encroachment, enter that. Then press CALCULATE.  You should see the patient’s life expectancy and how long it will take the GA to touch the fovea (the Cross Point). To change a single entry, just make the change and press CALCULATE again. You do not need to reset everything.

Touch RESET to clear all entries. 

Using the patient’s current fundus image, you can measure the distance easily with ImageJ software.

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ImageJ is a free, open-source program widely used in medical and scientific research for image analysis. It is a very small file that you can download and use to calculate the distance between the fovea and area of geographic atrophy in each patient.

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If you have a PC, choose the Windows version. If you have a Mac, select the Mac version. With a Mac, the first time you open it, you will have to agree to bypass the default security issue. You will need to unzip or extract the zipped file to use ImageJ. You can leave the unzipped files in your download area or move it to your desktop. ImageJ does not need to be installed. Just click on the file called ImageJ which has this icon:

The downloadable version will not work with iOS (iPad, iPhone) but there is an online version that works well. This is the link to the online version:

Fleckenstein, M., et al., The Progression of Geographic Atrophy Secondary to Age-
Related Macular Degeneration. Ophthalmology, 2018. 125(3): p. 369-390.

Keenan, T.D., et al., Progression of Geographic Atrophy in Age-related Macular
Degeneration: AREDS2 Report Number 16. Ophthalmology, 2018. 125(12): p. 1913-
1928.

Heier, J.S., et al., Pegcetacoplan for the treatment of geographic atrophy secondary to
age-related macular degeneration (OAKS and DERBY): two multicentre, randomised,
double-masked, sham-controlled, phase 3 trials. The Lancet, 2023. 402(10411): p. 1434-
1448.

Khanani, A.M., et al., Efficacy and safety of avacincaptad pegol in patients with
geographic atrophy (GATHER2): 12-month results from a randomised, double-masked,
phase 3 trial. Lancet, 2023. 402(10411): p. 1449-1458.