The influence of eyelid pressure and eye contour factors on rigid corneal contact lens fitting.

PURPOSE: This study aimed to investigate the impact of eyelid pressure (ELP) and eye contour factors on rigid corneal contact lens fitting.

METHODS

This prospective cross-sectional study involved 20 participants (one eye per person). Rigid corneal contact lenses with three different base curves were selected for each participant. The base curves were calculated according to the average keratometry value. The original value and its variations (+0.1 mm and - 0.1 mm) were considered. Eye contour factors, lens decentration under natural eye position (LD I) and full eyelid exposure (LD II), and lens vertical movement were taken by a Canon camera mounted on a digital slit lamp biomicroscope. Upper and lower ELPs were measured by a novel blepharo-tensiometer.

RESULTS

The mean values of LD I, LD II, and lens vertical movement significantly increased as the base curve increased (P＜0.001, ＜0.001, and = 0.005). Upper ELP was positively correlated with lens vertical movement of the three base curves (P = 0.047, 0.001, and 0.004). Furthermore, upper ELP (odds ratio [OR]: 1.039; 95 % confidence [CI]: 1.009-1.069; P = 0.009) and flat keratometry values (OR: 0.873; 95 % CI: 0.786-0.969; P = 0.011) independently influenced lens vertical movement.

CONCLUSIONS

ELP and base curve independently influenced rigid corneal contact lens fitting. Thus, ELP should be considered during rigid corneal contact lens fitting in clinical practice.