The Effect of Scleral Lens Reservoir Solution on Post-lens Fluid Turbidity and Settling in Patients With Keratoconus

OBJECTIVES: To evaluate the impact of using a high-viscosity hyaluronate solution in the fluid reservoir (FR) on post-lens fluid turbidity and the settling of scleral lenses (SLs). METHODS: Forty-four eyes of 22 keratoconus patients were fitted SLs. SLs applied to the right eye were filled with preservative-free sodium hyaluronate solution, whereas those applied to the left eye were filled with preservative-free saline. After SL fitting, high- and low-contrast visual acuities (VAs) were measured at 0, 4, and 8 hr. The optical density of the post-lens fluid was calculated using Scheimpflug tomography and graded from anterior-segment optical coherence (AS-OCT) images. Central corneal clearance and lens settling were measured with AS-OCT. RESULTS: High-contrast VA showed no significant change over time in either group. Low-contrast VA remained stable during 8 hr of SL wear in the right eyes, but low-contrast VA decreased at 4th and 8th hours in the left eyes. AS-OCT-based turbidity grading and the optical density increased over time, with no difference between the two solutions. The rate and amount of settling did not differ between the groups. CONCLUSIONS: High-viscosity sodium hyaluronate may sustain improved low-contrast vision in keratoconus patients compared with saline, without adversely affecting post-lens fluid turbidity or lens settling.