Flow cytometric DNA analysis of corneal epithelium.

We have modified an existing technique in order to perform DNA analysis by flow cytometry (FCM) of corneal epithelium from the mouse, rat, chicken, rabbit, and human. This protocol permitted an investigation of human corneal scrapings from several categories: normal, aphakic bullous keratopathy (ABK), keratoconus (KC), Fuch's dystrophy, edema, epithelial dysplasia, and lipid degeneration. No abnormal characteristic cell-kinetic profile was detected when averaged DNA histograms were compared statistically between the normal and either ABK, KC, edema, or Fuch's dystrophy groups. Abnormal DNA histograms were recorded for cell samples that were taken 1) from three individuals who had epithelial dysplasia and 2) from one individual diagnosed with lipid degeneration. The former condition was characterized by histograms that had a subpopulation of cells with an aneuploid amount of DNA or had higher than normal percentages of cells in the S and G2 + M phases of the cell cycle. Corneal cells from the patient who had lipid degeneration had an abnormally high percentage of cells in the G2 + M phases of the cell cycle. The availability of accurate DNA flow cytometric analysis of corneal epithelium allows further studies on this issue from both experimental and clinical situations.

Endothelial loss in corneal concussion injury.

A patient who suffered a concussion injury to the cornea from blunt trauma was followed up by means of endothelial photography for seven months. The endothelial cell loss resulting from this injury was almost 50%. Concussion injury to the cornea can cause significant endothelial damage instead of a transient dysfunction.

Conjunctival rhinosporidiosis.

Rhinosporidium seeberi is the fungus that causes rhinosporidiosis, which affects the mucocutaneous tissue of humans and domestic animals. Ten cases of conjunctival rhinosporidosis have been reported in the United States. This is a case report of conjunctival rhinosporidosis that is believed to be the 11th reported from the United States and the only case reported from Arkansas. A clinical and pathologic description of the disease is given.

Corneal epithelial dysplasia.

Corneal epithelial dysplasia without an identifiable limbal mass is an entity that is frequently overlooked in the differential diagnosis of chronic corneal epithelial disease. It is characterized by unilateral chronic irritative symptoms, decreased visual acuity, decreased sensation in the affected areas, and a somewhat characteristic appearance to the affected corneal epithelium. Mechanical debridement of the epithelium brings prompt relief from the symptoms, but recurrences are common. It appears that this entity is not widely recognized and should be considered in cases of chronic corneal epithelial disease of obscure etiology.