Multimodal Assessment of Corneal Erosions Using Optical Coherence Tomography and Automated Grading of Fluorescein Staining in a Rabbit Dry Eye Model

Purpose: To evaluate the potential use of anterior segment spectral domain optical coherence tomography (AS-SD-OCT) combined with an automated grading of fluorescein staining for assessment of corneal erosions in a rabbit short-term dry eye model. Methods: Twenty-one New Zealand white rabbits were anesthetized and eyes were kept open for 140 minutes to induce acute corneal desiccation. Rectangular scans of the cornea were performed using Spectralis AS-SD-OCT. Total corneal thickness, corneal epithelial thickness, and the percentage of epithelial erosion area (PEEA) were evaluated. Corneas were stained with fluorescein and graded automatically using EpiView and semi-automatically using Image.l. Spearman's rank-order correlations were calculated to compare the AS-SD-OCT PEEA and the two corneal staining scores. Results: Eye desiccation resulted in corneal epithelium erosions that covered 0.67% to 14.2% of the central cornea (mean +/- SD: 3.95% +/- 3.2%) by AS-SD-OCT. The percentage of corneal area positively stained with fluorescein ranged from 0.24% to 38.01% (mean +/- SD: 12.24% +/- 9.7%) by using ImageJ, correlating with the AS-SD-OCT PEEA (Spearman's p, 0.574; P = 0.007). The EpiView score ranged from 0.5 to 10.17 and was better correlated with the AS-SD-OCT PEEA score (Spearman's p, 0.795; P = 0.000017). Conclusions: Our study suggests that multimodal analysis of AS-SD-OCT and grading of fluorescein staining using EpiView software may enable quantitative assessment of corneal epithelial erosions in a rabbit short-term dry eye model. Translational Relevance: This multimodal imaging analysis may be applied for evaluation of superficial punctate keratitis associated with dry eye.