title: Riboflavin and ultraviolet a collagen crosslinking of the cornea for the treatment of keratitis.
abstract: OBJECTIVE
  To describe riboflavin and ultraviolet light (UV) collagen crosslinking as an effective treatment for infectious keratitis.
  
  
  METHODS
  A 25-year-old previously healthy female contact lens user was diagnosed with unilateral severe keratitis with unclear pathogenesis, although the clinical presentation suggested acanthamoeba as the infectious agent. A 4-mm diameter, annular, semi-opaque infiltrate was found on the paracentral parts of the cornea in the left eye (OS). Laboratory examinations for bacteria, herpes simplex, and acanthamoeba were performed, but no specific pathogen could be detected. Best corrected visual acuity (BCVA) at presentation was 20/1000. Treatment was initialized with broad-spectrum antibiotics also covering acanthamoeba. During the first month of treatment the keratitis progressed and the corneal thickness diminished. Therefore, treatment with riboflavin and UV collagen crosslinking was initiated.
  
  
  RESULTS
  After riboflavin and UV collagen crosslinking therapy, there was a rapid decrease of pain and necrotic material. Reepithelialization of the cornea started within a few days and was complete within a month. After 2 months, the wound had healed completely. Nine months after the UV treatment, BCVA was 20/30.
  
  
  CONCLUSIONS
  This case illustrates the positive effects of riboflavin and UV collagen crosslinking on presumed infectious keratitis with a satisfactory final visual outcome. This may be a promising new treatment for keratitis, although this remains to be elucidated in detail in future studies. Until more data are available this treatment should only be considered in therapy-refractive keratitis or ulceration and not in the first line of defence since it may have cytotoxic side effects.
authors.affiliation: Department of Ophthalmology, Regional Hospital of Västerås, Västerås, Sweden. hakan.moren@ltv.se
authors.forename: Håkan
authors.initials: H
authors.lastname: Morén
authors.forename: Malin
authors.initials: M
authors.lastname: Malmsjö
authors.forename: Jes
authors.initials: J
authors.lastname: Mortensen
authors.forename: Arne
authors.initials: A
authors.lastname: Ohrström
mesh_terms: D000328:Adult; D003094:Collagen / Q000378:metabolism*; D003319:Corneal Stroma / Q000378:metabolism*; D005260:Female; D006801:Humans; D007634:Keratitis / Q000188:drug therapy* / Q000378:metabolism / Q000382:microbiology; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000627:therapeutic use*; D012256:Riboflavin / Q000627:therapeutic use*; D014466:Ultraviolet Rays; D014792:Visual Acuity / Q000502:physiology; D014945:Wound Healing
chemical_list: D017319:Photosensitizing Agents; D003094:Collagen; D012256:Riboflavin