Establishing an objective biomarker for corneal cystinosis using a threshold-based Spectral domain optical coherence...

Area of Science:

• Ophthalmology
• Medical Imaging
• Biomarker Development

Background:

• Ocular cystinosis involves cystine crystal deposition in the cornea.
• Accurate quantification of these deposits is crucial for disease management.
• Anterior segment optical coherence tomography (AS-OCT) offers high-resolution imaging of the cornea.

Purpose of the Study:

• To develop a semi-automated, threshold-based image segmentation algorithm.
• To objectively quantify corneal cystine crystal deposition using AS-OCT.
• To assess the algorithm's efficacy in differentiating patients from controls.

Main Methods:

• A prospective, observational study included 88 eyes of cystinosis patients and 68 eyes of healthy controls.
• AS-OCT imaging was performed on all participants.
• A semi-automated grey scale value-based threshold algorithm was developed to quantify corneal crystals.

Main Results:

• Corneal crystals appeared as hyperreflective deposits in AS-OCT B-scans.
• The algorithm effectively delineated crystals at higher grey scale thresholds.
• Significant differences in crystal deposition were observed between patients and controls (p < 0.001).
• An age-dependent depth distribution of crystal deposition was detected.

Conclusions:

• Objective quantification of corneal cystine crystal deposition is feasible with AS-OCT.
• This quantitative method can serve as a novel biomarker.
• It holds potential for ocular disease control and topical treatment monitoring.