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Abstract
Purpose
The present study compares, using a new generation high‐ resolution in vivo confocal microscope, the corneas of patients who underwent photorefractive keratectomy (PRK) 10 years previously with those of healthy persons.
Case summary
A confocal microscope (Confoscan 4.0, Fortune Technology, Italy) was used to get the data from healthy volunteers and patients. Corneal cross‐ sectional images of the epithelium, Bowman’s layer, stromal layer (anterior, middle and posterior keratocyte), Descemet’s membrane, and endothelium were compared. In PRK corneas, the superficial epithelium was nearly intact and the subbasal nerve plexus was visible, but some hyperreflective areas were also found in the nerve plexus. Because of the absence of the Bowman’s layer, some ECM and keratocytes were visualized in their optical section. Although anterior keratocytes showed uneven distribution with less cellularity, middle and posterior keratocytes looked unaffected. Likewise, there were no differences in the endothelium between the two groups.
References
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Figure 1.
Confocal microscopic images of the subbasal nerve plexus layer of the cornea in the control (A) and corresponding post-PRK corneas (B). (A) Normal subbasal nerve plexus. (B) In post-PRK corneas, the anterior keratocyte and some hyperreflective ECM were imaged together with regenerated nerve plexus (arrow).
Figure 2.
Confocal microscopic images of the anterior stromal layer of the cornea in the control (A) and corresponding post-PRK corneas (B). (A) Evenly distributed anterior keratocytes. (B) Unevenly distributed anterior keratocytes (arrow) showed decreased cellular density and some hyperreflectivity.
Figure 3.
Confocal microscopy images of the middle and posterior stromal layer of the cornea in the control (A, C) and corresponding post-PRK corneas (B, D). (A) Midstromal keratocytes. (B) Only minor changes were observed in the post-PRK midstroma. (C, D) The posterior cornea appeared unaffected in both groups.
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