Assessment of corneal reflex sensitivity and vision-related functions among contact lens wearers: a cross-sectional study

To evaluate the effects of soft (SCL), Rigid Gas Permeable (RGP), and scleral (ScCL) contact lenses on corneal reflex sensitivity and vision-related functions in CLs wearers. This cross-sectional clinical study included 89 participants aged 20–45 years, allocated to four groups: SCL, RGP, ScCL, and non-CLs wearers (controls). Unilateral assessment of the right eye was conducted for corneal reflex sensitivity, tear film quantity or volume (Schirmer’s test), and visual acuity (Snellen chart). The ocular surface disease index (OSDI) and CLs dry eye questionnaire-8 (CLDEQ-8) were used to evaluate vision-related function. Data were analysed using SPSS. Corneal reflex sensitivity varied significantly among groups ( p < 0.001). The SCL group had relatively better results, with shorter response times than RGP and ScCL users, indicating greater preservation of corneal sensitivity. Visual acuity differed significantly with SCLs wearers achieving the best results among lens users. Chi-square analysis of OSDI/CLDEQ-8 outcomes against CL material type found no significant association at the individual item level. A significant association was found for the OSDI functional-limitation subtotal (Subtotal B: reading, driving at night, computer use, TV) with CL type (χ²(4) = 14.72, p = 0.005). RGP CL users reported more functional impairment than SCL users. Within CLs users groups and among the OSDI/CLDEQ items-8, Kruskal–Wallis analysis showed a statistically significant of CL-type effect on only reading (Q6) and poor vision (Q5). VA correlated significantly with blurred vision (Q4) within the RGP CL subgroup (ρ=-0.52, p = 0.015) and with watching TV (Q9) within the SCL subgroup (ρ=-0.44, p = 0.031); no significant correlation was found within the ScCL subgroup. This supports the therapeutic option of ScCL for dry eye, as no wearers reported any ocular discomfort, visual functions difficulties, or sensitivity to environments. Corneal reflex sensitivity, Schirmer test, duration of wearing CLs, age, and VA all differ significantly across CL-type groups. SCLs had a favourable impact on vision-related functions however, ScCL are recommended as a therapeutic option in many ocular surface diseases because of the positive impacts on visual functions. Regular ocular examinations and patient education are essential to minimize complications associated with CLs wear and to preserve visual functions during prolonged CLs use.