Visual Improvement With Wavefront-Guided Scleral Lenses for Irregular Corneal Astigmatism

To report interim results of a single center, randomized, double-blind, crossover-controlled clinical trial comparing wavefront-guided (wfg) scleral lenses (SLs) to traditional scleral lenses (tSLs) for patients with a history of irregular corneal astigmatism (ICA).

Thirty-one ICA eyes of 18 participants were reviewed, 23 with keratoconus, six postcorneal refractive ectasia, and two postpenetrating keratoplasty. Patients with corneal or lens opacities were not excluded from participating. Participants underwent a diagnostic lens-based fitting with a tSL with standard spherocylindrical optics. Once the tSL was finalized, a comprehensive wavefront aberrometer-based system was used to capture the residual aberration of the tSL under scotopic conditions without pharmacologic dilation, and these data were used to create a wfgSL. Once the tSL and wgfSL were finalized, a double-blinded, randomized, crossover was conducted where the participants received lens A (tSL or wgfSL) or lens B (the alternative), each worn for a 4±1 week interval. Measurements of the visual acuity (VA) and total higher-order root mean squared (HORMS) were recorded at each interval under controlled lighting conditions. At the final visit, patient subjective preference for lens A or lens B was recorded.

The average HORMS for a fixed 5-mm pupil was 0.68±0.31 μm for tSL and 0.29±0.18 μm for wfgSL. Wavefront-guided SL provided an average HORMS improvement of 56% ( P <0.001). All eyes showed a reduction in HORMS, ranging from 18% to 83%. Wavefront-guided SL provided an average VA improvement of 0.12±0.11 logMAR ( P <0.01). Seventy-one percent of eyes showed one line or greater improvement, 26% showed no improvement, and 3% showed a reduction of VA with the wfgSL. The average VA with tSL was 0.14±0.16 logMAR and 0.03±0.11 logMAR for wfgSL. Seventeen of 18 patients subjectively preferred wfgSL.

In eyes with ICA, wfgSL reduced HORMS and improved VA when compared with tSL. Patients subjectively preferred wfgSL to tSL. These interim results demonstrate the feasibility and generalizability of wfgSL in a typical clinical practice environment.