Assessment of Corneal Biomechanics and Intraocular Pressure With Scleral Lenses of Different Diameters

Purpose: To evaluate the short-term influence of scleral lenses (SL) with different diameters on intraocular pressure (IOP) and corneal biomechanics. A secondary objective was to investigate the relationship between fluid reservoir (FR) thickness and IOP and biomechanical parameters. Methods: Thirty healthy subjects were randomly fitted with L1 (diameter of 15.80 mm) and L2 (diameter of 16.80 mm) on the right eye and worn for 2 hr. On IOP and corneal biomechanical parameters were measured with the CORVIS ST before and after SL removal. Fluid reservoir thickness at 0 and 2 hr of wear was measured using anterior segment optical coherence tomography. Results: Biomechanical parameters decreased after removal of L1 (−1.04±1.47 mm Hg) ( P <0.01) and L2 (−0.80±1.74 mm Hg) ( P =0.02). The biomechanical parameters A1T (−0.11±0.18 ms) ( P =0.01) and SP-A1 (−4.29±9.97 mm Hg/mm) ( P =0.02) decreased after L1 removal, whereas a decrease in highest concavity time (−0.21±0.50 m/s) ( P =0.03) and an increase in highest concavity radius (+0.17±0.43 mm) ( P =0.04) were observed after L2 removal. A significant, negative, and moderate correlation was found between highest concavity deformation amplitude and FR thickness with L1 (r=−0.42, P =0.02). Conclusions: The small changes in corneal biomechanical parameters and IOP values induced by short-term SL wear have no significant clinical impact and were not influenced by the diameter of the SL.