Morphological changes in the conjunctiva, episclera and sclera following short-term miniscleral contact lens wear in rigid lens neophytes

Abstract

Purpose: To quantify the influence of short-term wear of miniscleral contact lenses on the morphology of the corneo-scleral limbus, the conjunctiva, episclera and sclera. Methods: OCT images of the anterior eye were captured before, immediately following 3. h of wear and then 3 h after removal of a miniscleral contact lens for 10 young (27 ± 5 years) healthy participants (neophyte rigid lens wearers). The region of analysis encompassed 1. mm anterior, to 3.5 mm posterior to the scleral spur. Natural diurnal variations in thickness were measured on a separate day and compensated for in subsequent analyses. Results: Following 3. h of lens wear, statistically significant tissue thinning was observed across all quadrants, with a mean decrease in thickness of -24.1 ± 3.6 μm ( p< 0.001), which diminished, but did not return to baseline 3. h after lens removal (-16.9 ± 1.9 μm, p< 0.001). The largest tissue compression was observed in the superior quadrant (-49.9 ± 8.5 μm, p< 0.01) and in the annular zone 1.5. mm from the scleral spur (-48.2 ± 5.7 μm), corresponding to the approximate edge of the lens landing zone. Compression of the conjunctiva/episclera accounted for about 70% of the changes. Conclusions: Optimal fitting miniscleral contact lenses worn for three hours resulted in significant tissue compression in young healthy eyes, with the greatest thinning observed superiorly, potentially due to the additional force of the eyelid, with a partial recovery of compression 3 h after lens removal. Most of the morphological changes occur in the conjunctiva/episclera layers.