Comparison of Higher Order Aberrations between On- and Off- Eye Scleral Lenses in Dry Eye and Ocular Surface Disease Patients

Background: The pilot study measured and compared higher order optical aberrations
(HOA) with scleral contact lenses on-eye and off-eye in a group of subjects with
confirmed Dry Eye Syndrome (DES). It has been confirmed that the corneal surface and
tear film irregularities associated with DES increase the amount of HOA in the optical
system of the eye, leading to the detrimental visual symptoms of glare, halos and
decreased contrast sensitivity. Methods: A sample of subjects, N=8, with a confirmed
diagnosis of DES, had an initial fluorescein tear break-up time (TBUT) performed on
them. Subjects with a TBUT of <10 seconds were included. All subjects were fit in
scleral lenses OU. Two measurements of total HOA and total aberrations were performed
on each eye; i) scleral lens off-eye (SCL or naked eye) and ii) scleral lens on eye – using
the Nidek OPD – Scan III. Results: Root Mean Square (RMS) values of the total HOA
and total aberrations (higher order + lower order) were obtained and analyzed. Dry eye
subjects showed a statistically insignificant reduction of 0.02 RMS in total HOA with
scleral lenses on-eye vs. off eye, t=1.89; p<0.35. Subjects showed a statistically
significant increase of 0.21 RMS in total aberrations (H+L) with scleral lenses on-eye vs.
off-eye, t=2.36; p<0.03. Conclusions: By vaulting the cornea and filling in any corneal
irregularities with the tear reservoir, a scleral lens theoretically creates a new, regular
anterior refracting surface for the eye and a continuous optical system. There was no
statistically significant reduction in total HOA with scleral lenses for dry eye patients.
This study showed no significant evidence that scleral lens technology reduces HOA in
dry eye patients, compared to SCL’s or naked eye, to resolve function vision problems
such as glare, halos, and reduced contrast sensitivity