Do Scleral Contact Lenses Affect Pupillary Light Response in Patients With Keratoconus?

OBJECTIVES: To investigate the effects of scleral lenses on ocular aberrations, static and dynamic pupil functions in patients with keratoconus. METHODS: Thirty-nine eyes from 31 patients diagnosed with moderate to severe keratoconus. Ocular aberration measurements (Pentacam AXL wave) and pupillometry measurements using automated pupillometry were recorded for all patients, both before and after the wearing of scleral lenses. RESULTS: After the application of scleral lenses, considerable improvements were noted in best-corrected visual acuity (BCVA), lower-order aberration (LOA), higher-order aberration (HOA), vertical coma, horizontal coma, and spherical aberration values in ocular aberration (P<0.05). In static and dynamic pupillometry, significant decreases were observed in high photopic pupil diameter (PD), low photopic PD, mesopic PD, scotopic PD, contraction velocity, and dilation velocity (P=0.039, P<0.001, P<0.001, P=0.023, P=0.001, and P=0.016, respectively). The change in BCVA after scleral lenses correlated with the change in LOA, HOA, vertical coma, spherical aberration, low photopic PD, and mesopic PD values (P<0.05). CONCLUSIONS: Scleral lenses cause notable changes in static and dynamic pupil functions. Besides neutralizing LOA and HOA, the decrease in low-photopic and mesopic PD might contribute to improved BCVA and enhanced visual quality after the use of scleral lenses.