CK induces morphological changes on histological study

Paris—Conductive keratoplasty (CK) produced collagen shrinkage changes in human corneas that were localized to 80% of the stromal depth compared with normal control corneas, according to Tatiana Naoumidi, MD.

Dr. Naoumidi and colleagues of the University of Crete Medical School, Greece, applied three CK spots to one cornea of 6 patients with peripheral keratoconus, all of whom had had penetrating keratoplasty (PK). The spots were applied in the periphery of the cornea; corneal buttons were assessed 1 and 3 days and 1, 3, and 6 month after the procedure.

Dr. Naoumidi reported at the annual meeting of the European Society of Cataract and Refractive Surgeons that on Days 1 and 3 after CK, there were small areas of detachment observed between the basal layer of the epithelial cells and Bowman's layer, which corresponded to the area that the top penetrated. On Day 7, the appearance of the epithelium was almost normal.

In all the corneal samples studied, the collagen layers had a crumpled appearance in up to 80% of the stromal depth and the affected area was cylindrical in shape with a diameter of 120 µm. Folds in Descemet's membrane between the CK spots were seen up to 6 months after the procedure.

"We found CK to be safe and efficient in that it caused changes in the corneal collagen that could be described as crumpled layers of collagen. The application reached the depth of 80% of the corneal thickness and the results were stable through the 6-month period of observation. The damage to the surrounding tissue was minimal," she concluded.