Diurnal Variation in Straylight in Patients With Fuchs Endothelial Corneal Dystrophy and Controls.

Area of Science:

• Ophthalmology
• Corneal Diseases
• Visual Optics

Background:

• Fuchs endothelial dystrophy affects corneal transparency and can cause visual disturbances.
• Diurnal variations in visual function are known, but their specific role in Fuchs dystrophy requires further investigation.

Purpose of the Study:

• To examine diurnal changes in intraocular straylight in patients with Fuchs endothelial dystrophy.
• To correlate these changes with corneal parameters and subjective visual complaints.
• To compare diurnal straylight patterns between Fuchs dystrophy patients and healthy controls.

Main Methods:

• Prospective study in Germany and the Netherlands involving 71 Fuchs dystrophy patients and 34 healthy controls.
• Intraocular straylight measured using C-Quant; corneal thickness and backscatter assessed with Scheimpflug imaging.
• Diurnal changes modeled using an exponential decay model, with intensive morning measurements in controls.

Main Results:

• Healthy controls showed a transient morning straylight increase of 0.22 log(s) lasting ~22 minutes.
• Fuchs dystrophy patients exhibited a similar morning increase (0.21 log(s)) but prolonged for up to 4 hours.
• Straylight correlated positively with corneal backscatter (r=0.21) and thickness (r=0.46) in Fuchs patients.

Conclusions:

• Fuchs dystrophy patients experience a prolonged diurnal increase in intraocular straylight compared to healthy individuals.
• This prolonged straylight exacerbation may contribute to the subjective visual complaints reported by patients.
• The findings suggest a pathological alteration of a physiological diurnal change in Fuchs dystrophy.