Abstract
Purpose :
Impression-based scleral lenses are manufactured to exactly match anterior ocular surface contour. This exact match should eliminate lens decentration and induced vector forces on the cornea, which should optimize fit, visual acuity and comfort. Furthermore, precise alignment between the lens haptic and ocular surface should reduce the risk of ocular surface compromise. This study assessed the visual and physiological outcomes of patients fit with impression-based scleral lenses.
Methods :
A multi-center retrospective chart review identified patients fit with impression-based scleral lenses at three specialty contact lens practices between January 1 2013 and June 30 2019. Visual acuity was recorded prior to as well as after impression-based lens fitting. In addition, the presence or absence of corneal and conjunctival staining was noted before and after impression-based lens wear.
Results :
A total of 44 patients (70 eyes) who had been fit with impression-based scleral lenses were identified. Twenty-six patients were fit bilaterally, OD only was fit in 9 patients, and OS only was fit in 9 patients. Nine patients wore no correction prior to impression-based lens fitting, 5 wore a combination of spectacles and contact lenses, 7 wore spectacles only, and 23 wore contact lenses. The habitual correction logMAR acuity was 0.40 [0.56] (mean [SD]) significantly improving to logMAR acuity 0.22 [0.44] with impression-based lenses (n=69, p<0.01). The presence or absence of corneal staining was noted for 65 eyes and the presence or absence of conjunctival staining was recorded for 55 eyes. Corneal staining was present in 28 eyes prior to impression-based scleral lens fitting and remained in 22 eyes after fitting. Conjunctival staining was present in 22 eyes prior to impression-based scleral lens fitting and was persistent in 20 eyes after fitting.
Conclusions :
Visual acuity with impression-based lenses improved significantly compared to baseline with habitual correction. However, improvement in visual acuity was similar to that which has been reported with standard scleral lens designs. While the number of eyes with corneal or conjunctival staining decreased slightly with impression-based lenses, a majority of eyes that exhibited staining prior to impression-based lens wear continued to show staining after being fit with these lenses.
This is a 2020 ARVO Annual Meeting abstract.