Safety and Effectiveness of the PXL-Platinum 330 System for Cornea Crosslinking in Eyes With Cornea Thinning

Inclusion Criteria: * healthy subjects with no other medical or ocular conditions Subjects who have one or both eyes that meet criteria 1 and 1 or more of the following criteria will be considered candidates for this study: * 18 years of age or older * Presence of central or inferior steepening (on Pentacam topograph) * Axial topography consistent with keratoconus, post-surgical ectasia, or pellucid marginal degeneration (See keratoconus grading section 7.0 for details) * Presence of one or more findings associated with keratoconus or pellucid marginal degeneration on slit lamp exam 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 on simK or Pentacam * I-S keratometry difference \> 1.5 D on the Pentacam/Galilei/Orbscan/Cassini map or topography map * Posterior corneal elevation \>16 microns (µm on Pentacam tomography) * Thinnest corneal point \<485 microns (ultrasound pachymetry or Pentacam tomography) * Predicted Post LASIK/PRK stromal ablation depth \<350 microns or expected keratometry \>47.2 D, or patients undergoing PRK/SMILE in keratoconus suspect eyes * Bacterial or fungal corneal keratitis persistent and not responding despite \> 2 weeks of standard antimicrobial therapy or with rapid progression of corneal thinning, with loss of \>25% corneal thickness * 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 * Signed written informed consent * Willingness and ability to comply with schedule for follow-up visits Exclusion Criteria: * active infections, collagen vascular disease, allergic to product All subjects meeting any of the following criteria will be excluded from this study: * Eyes classified as either normal or atypical normal on the severity grading scheme. * Corneal pachymetry at the screening exam that is \<300 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 cognitive or ambulatory conditions that would prevent eye drop compliance with medications * Patients with nystagmus or any other condition that would prevent a steady gaze during the CXL treatment or other diagnostic tests. * Patients with a current condition that, in the physician's opinion, would interfere with or prolong epithelial healing.