Aberrations are the spreading of light from a point focus. Aberrations of the eyes can be objectively evaluated with a wavefront aberrometer. Lower order aberrations such as defocus and astigmatism can be corrected with glasses and traditional/disposable soft contact lenses. Patients with ectatic corneal disease, such as keratoconus, or irregular astigmatism cause by surgery, trauma or disease, experience vision that is unlikely to be adequately corrected with glasses or disposable soft contact lenses due to higher order aberrations (HOA). HOA's cause halos, flare, glare, starbursts, doubling, smearing or ghosting of vision. Specialty contact lenses, such as scleral lenses, can be used to mask the irregularity of the cornea, reducing HOA's and improving vision. In many patients the resultant vision, though improved, still has some level of residual HOA's affecting the quality of vision. Custom scleral lenses with customized wavefront guided optics can be used to reduce residual HOA's and improve vision further. These lenses have been referred to as higher order aberration correcting scleral lenses or HOA correcting sclerals and wavefront guided scleral lenses or WFG sclerals.

The purpose of this study is to investigate the effect of an advanced technique for designing custom scleral contact lenses to further improve vision in keratoconus or irregular astigmatism by reducing residual aberrations. The derived custom scleral lenses will include customized aberration correcting optics, guided by a wavefront aberrometer measurements. These lenses are custom made based on the individual measurements from an eye.The primary objective of this study is to evaluate the vision differences between traditional scleral lens optics and customized scleral lens optics. In particular, the investigators will compare efficacy in reducing aberrations and improvement in vision.

Inclusion Criteria:

-A diagnosis of keratoconus or irregular astigmatism

Exclusion Criteria:

• Patients with other visually significant ocular pathology.
• Inability to apply or remove a scleral lens.