Comparison of clinical and topographical outcomes of hybrid and scleral lenses in advanced keratoconus

Objectives: To evaluate and compare the effects of hybrid contact lenses (HCLs) and mini-scleral contact lenses (MSCLs) on visual acuity, spherical equivalent, topographic astigmatism, and higher-order aberrations (HOAs) in eyes with advanced keratoconus. Methods: We reviewed the medical records of 43 eyes of 27 patients diagnosed with advanced keratoconus fit hybrid contact lenses (AirFlex®) and mini-scleral contact lenses (Mini-misa®). Pre-fitting examinations included best corrected visual acuity (BCVA), spherical equivalent, topographic findings (topographic astigmatism, maximum keratometry, mean keratometry, central corneal thickness, thinnest corneal thickness, and corneal HOAs. Post-fitting examinations included lens corrected visual acuity, spherical equivalent, topographic astigmatism, corneal HOAs, and contact lens-related discomfort symptoms. Results: Mean BCVA (log MAR) improved significantly from 0.65±0.27 to 0.14±0.09 with HCL and 0.58±0.25 to 0.15±0.13 with MSCL (p<0.05). The mean spherical equivalent and topographic astigmatism measurements decreased significantly in both groups (p<0.05). Eight patients in the HCL group experienced lens-related discomfort. Root-mean square HOA decreased significantly in both groups (p<0.05). Conclusion: Significant improvements in visual acuity, spherical equivalent, topographic astigmatism, and HOAs were observed with both lenses. However, higher patient comfort with scleral lenses may lead to higher compliance in patients with advanced keratoconus.