Abstract
Purpose :
To identify the potential of the optical coherence tomography (OCT) speckle parameters in the assessment of the effect of contact lens wear on cornea.
Methods :
Six regular contact lens wearers (3M/3F) aged 21 to 26 years were enrolled in the study. Subjects were fitted with Biofinity lenses and undergone five measurement sessions that included OCT anterior eye imaging. Subjects were given the same recommended cleaning solution and instructed to not exceed the wear above 12 hours daily. Right eye of each subject was examined. Three horizontal OCT image acquisitions (B-scans) were performed at the baseline (B1, without contact lens), 3 hours post-fit (3h), 14 days mid-wear (14d), 28 days final-day-wear (28d), and at the final baseline (B2), 3 days after lens discontinuation. Statistical parameters of OCT speckle such as the scale and shape parameters of the Burr 2 and Gamma distributions as well as the contrast ratio (CR) were calculated in regions of interest (ROI) encompassing central corneal stroma and contact lens. Median parameters from every three acquisitions were taken for further analysis.
Results :
Agreeable results among the considered median parameters were identified, showing (i) the combined effect of contact lens and wear time on stromal speckle characteristics as well as (ii) the effect of wear time on contact lens speckle characteristics. Figure 1 shows illustrative results for ROI width of 1 mm (top row, outlined in red). For stroma, evident but not statistically significant trends have been observed in all considered parameters of OCT speckle (bottom-left) whereas for contact lens, no evident trends were identified (bottom-right). In this particular case, changes in CR of stromal OCT speckle are evident 3 hours post-fit with respect to B1. Further, at 14d, CR regresses to level at B1 indicating negligible effect of contact lens on stromal speckle. After 28 days of wear, the variation in CR among the subjects is the greatest. No substantial differences in CR are identified between B1 and B2. Finally, no differences were identified in CL OCT speckle between 3g, 14d and 28d image acquisitions.
Conclusions :
The results of this pilot study has identified the potential of the statistical characterization of OCT speckle in the assessment of the effect of contact lens wear in-vivo.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.