This trial compares two methods of corneal crosslinking, a procedure that strengthens the cornea using special eye drops and light. It targets people with progressive keratoconus or corneal ectasia, conditions where the cornea weakens and bulges out. The treatment aims to make the cornea more stable and prevent further vision problems. Corneal crosslinking (CXL) has become the standard treatment for rapidly progressing keratoconus.