Inclusion Criteria:
Subjects who have one or both eyes that meet criteria 1 \& 2 and 1 or more of the following criteria will be considered candidates for this study.
- 12 years of age or older
- Evidence of progressive keratoconus (based on the discretion of the physician as evidenced by an increase in astigmatism, asymmetry, or worsening vision in the last 3 or more months)
- Presence of central or inferior steepening.
- Axial topography consistent with keratoconus
- Presence of one or more findings associated with keratoconus such as:
- Fleischer ring
- Vogt's striae
- Decentered corneal apex
- Munson's sign
- Rizzutti's sign
- Apical Corneal scarring consistent with Bowman's breaks
- Scissoring of the retinoscopic reflex
- Crab-claw appearance on topography
- Steepest keratometry (Kmax) value ≥ 47.20 D
- I-S keratometry difference > 1.5 D on the Pentacam/Galilei/Orbscan/Cassini map or topography map
- Posterior corneal elevation >16 microns
- Thinnest corneal point <485 microns
- AvaGen (Avellino Labs) genetic testing keratoconus risk score of 67 or higher (high risk).
- Signed written informed consent
- Willingness and ability to comply with schedule for follow-up visits
- For Contact Lens Wearers Only: Removal of contact lenses for the required period of time prior to the screening refraction:
- Contact Lens Type Minimum Discontinuation Time:
- Soft: 1 Week
- Soft Extended Wear: 2 Weeks
- Soft Toric: 3 Weeks
- Rigid gas permeable: 2 Weeks per decade of wear
- Scleral Lenses
- Investigator Discretion \[Discontinuation of scleral lenses not required unless there is clinical evidence of corneal hypoxia (e.g. corneal neovascularization) at time of screening\]
- Signed written informed consent
- Willingness and ability to comply with schedule for follow-up visits
Exclusion Criteria (any of the following are reasons for exclusion):
- Eyes classified as either normal or atypical normal on the severity grading scheme.
- Corneal pachymetry at the screening exam that is <330 microns at the thinnest point in the eye(s) to be treated.
- Previous ocular condition (other than refractive error) in the eye(s) to be treated that may predispose the eye for future complications, for example:
- History of or active corneal disease (e.g., herpes simplex, herpes zoster keratitis, recurrent erosion syndrome, acanthomeoeba, etc.)
- Clinically significant corneal scarring in the CXL treatment zone that is not related to keratoconus or, in the investigator's opinion, will interfere with the cross-linking procedure.
- Pregnancy (including plan to become pregnant) or lactation during the course of the study
- A known sensitivity to study medications
- Patients with nystagmus or any other condition that would prevent a steady gaze during the CXL treatment or other diagnostic tests.
- Patients with active medical implants (e.g. cardiac pacemakers)'
- Patients who are aphakic/ pseudophakic