Wavefront Guided Scleral Lenses for Keratoconus and Irregular Astigmatism (WFG Sclerals)

Custom Anterior Surfacing of Scleral Lens for Vision Quality Improvement in Patients With Keratoconus or Irregular Astigmatism

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.

Keratoconus, Irregular Astigmatism, Corneal Ectasia, Aberration, Corneal Wavefront, Wavefront Aberration, Corneal, Pellucid Marginal Corneal Degeneration, Keratoglobus

Scleral lenses, Scleral lens, Wavefront guided scleral lenses, Higher order aberrations, HOA scleral lenses, Sclerals, Higher order aberration correction, Custom scleral lenses, Wavefront guided, Keratoconus, Irregular Astigmatism, WFG scleral lenses

Total higher order aberrations with traditional scleral lenses will be compared with wavefront guided scleral lenses for all eyes. A secondary analysis of this endpoint, the change in total higher order aberrations with wavefront guided scleral lenses from dispense to 4 week follow up, will be evaluated.

Visual acuity with traditional scleral lenses will be compared to visual acuity with wavefront guided scleral lenses for all eyes. A secondary analysis of this endpoint, the change in visual acuity from dispense to 4 week follow up, will be evaluated for signs of neural adaptation.

Contrast sensitivity with traditional scleral lenses will be compared to contrast sensitivity with wavefront guided scleral lenses for all eyes. A secondary analysis of this endpoint, the change in contrast sensitivity with wavefront guided scleral lenses from dispense to 4 week follow up, will be evaluated for signs of neural adaptation.

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.