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

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.

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.

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).

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.