Persistent corneal haze after excimer laser photokeratectomy in plasminogen-deficient mice

Invest Ophthalmol Vis Sci. 2000 Jan;41(1):67-72.


Purpose: Excimer laser photorefractive keratectomy creates a nonvascular wound of the cornea. Fibrin deposition and resolution after excimer laser photokeratectomy were investigated in relation to corneal repair and restoration of clarity in mice with a genetic deficiency of plasminogen.

Methods: A Summit Apex Laser (Summit, Waltham, MA) was used to perform 2-mm, 175-pulse, transepithelial photoablations that resulted in deep stromal keratectomies. Photokeratectomy was performed on the corneas of plasminogen-deficient (Plg-/-) mice and littermate control animals. Eyes were examined for re-epithelialization and clarity throughout the 21-day observational period. Histologic sections were taken during the observational period and fibrin(ogen) was detected immunohistochemically.

Results: Re-epithelialization was rapid and complete within 3 days in both control and Plg-/- animals. Exuberant corneal fibrin(ogen) deposition was noted in Plg-/- mice and sparse fibrin(ogen) deposition in control mice on days 1 and 3 after injury. Fibrin(ogen) deposits resolved in control mice but persisted in Plg-/- mice (74% of eyes at 21 days; P < 0.004). Corneal opacification, scarring, and the presence of anterior chamber fibrin(ogen) occurred in plasminogen-deficient mice but not in control mice.

Conclusions: Fibrin(ogen) deposition occurs during corneal wound repair after photokeratectomy. Impaired fibrinolysis in Plg-/- mice caused persistent stromal fibrin deposits that correlated with the development of corneal opacity.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Cornea / metabolism
  • Cornea / pathology*
  • Cornea / surgery
  • Corneal Opacity / etiology*
  • Corneal Opacity / metabolism
  • Corneal Opacity / pathology
  • Fibrin / metabolism
  • Fibrinogen / metabolism
  • Immunoenzyme Techniques
  • Lasers, Excimer
  • Mice
  • Mice, Mutant Strains
  • Photorefractive Keratectomy / adverse effects*
  • Plasminogen / deficiency*
  • Wound Healing


  • Fibrin
  • Fibrinogen
  • Plasminogen