Abstract
Purpose :
Fuchs' Dystrophy affects one out of 30 adults over 40 and is a leading indication for endothelial keratoplasty in North America. Grading disease severity depends on objective tests such as specular microscopy, pachymetry, center-to-periphery ratio, and retro-illumination photography. However, each test has its limitations: the former three tests have varied baseline values amongst individuals and require expensive equipment, and the latter requires dilation and an experienced ophthalmic photographer. Here, we test a method which we hypothesize can objectively determine grading of Fuchs’ Dystrophy with a common baseline of zero and without requiring dilation.
Methods :
Images were taken at the slit lamp with an iPhone 4S and analyzed using ImageJ. Half the slit beam in images was fractioned into four equally sized sections (Image 1), and the number of guttae were recorded within each (Image 2). The ratio of guttae in the peripheral section to those in the center section was correlated to the clinical severity (on a scale of 0.5 to 5) through Spearman’s Correlation Coefficient. A Wilcoxon rank sum test was used to compare cases of mild disease (clinical severity of 0.5-2) to severe disease (clinical severity of 3-5).
Results :
Images from 15 patients, of whom 9 (60%) were female, were analyzed. The cohort had an average age of 67.13 years and a mode Fuchs’ clinical severity of 4+ on the Krachmer Scale. An increase in the peripheral/center guttae ratio correlated with an increased Fuchs’ clinical severity (S=201.56; p=0.017). Moreover, there was a significant difference in the peripheral/center guttae ratio between mild and severe cases (W=33; p=0.031).
Conclusions :
The ratio of guttae between the peripheral and central cornea can help determine the clinical severity of Fuchs’ Dystrophy. Our technique is advantageous because it avoids eye dilation and allows for a standardized baseline of zero guttae which can be used to gauge disease progression. Moreover, it requires less skill and fewer resources, so it has the potential of improving management of patients with Fuchs’ Dystrophy in low-resource settings. Further studies are needed to validate this technique on a larger cohort.
This is a 2020 ARVO Annual Meeting abstract.