Spectacles for Patients With Down Syndrome

Individuals with Down syndrome suffer from significant ocular complications including high
levels of lower-order refractive error (sphere and cylinder) and elevated levels of
higher-order aberrations. These optical factors likely contribute to the poor acuity observed
in this population. Current clinical prescribing practices may under-serve this community, as
the cognitive demands of the subjective refraction sequence are difficult for this population
and often leave clinicians to prescribe from objective clinical findings that target full
correction of sphero-cylindrical refractive error. This prescribing practice can lead to
sub-par outcomes given the fact that full lower-order corrections can exacerbate the effects
of higher-order aberrations in more aberrated eyes.

For this study, individuals with Down syndrome will be dispensed three pairs of spectacles
for 2 months each, in random order: one clinically-derived, and two objectively-derived
refractions based upon methods designed to optimize a given metric of retinal image quality
which takes into consideration the wavefront aberration measurements of the eye. Both initial
and adapted visual acuity in the presence of each correction will be evaluated to determine
whether the objectively-derived refractions outperform clinically-derived refractions.

Inclusion Criteria:

- Diagnosis of Down syndrome

Exclusion Criteria:

- Nystagmus (Involuntary beating movement of the eyes)

- Visually significant media opacities (e.g. cataracts or corneal scars)

- Strabismic amblyopia (reduced vision in one eye related to a constant eye-turn)

- Anisometropic amblyopia (reduced vision in one eye related to a long-standing
uncompensated difference in prescription between the two eyes)