J Korean Ophthalmol Soc.  2009 Feb;50(2):303-307. 10.3341/jkos.2009.50.2.303.

Confocal Microscopic Changes in the Cornea 10 Years After Photorefractive Keratectomy

• Shin MK
• Koo GH
• Lee JS

• KMID: 2212068
• DOI: http://doi.org/10.3341/jkos.2009.50.2.303

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.
CONCLUSIONS
Ten years after PRK, the subbasal nerve plexus and anterior keratocytes showed histologic changes after corneal wound recovery.

Keyword

Confocal microscopy; Photorefractive keratectomy

MeSH Terms

Cornea
Dental Porcelain
Descemet Membrane
Endothelium
Epithelium
Humans
Microscopy, Confocal
Photorefractive Keratectomy
Dental Porcelain

Figure

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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).

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  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.

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  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.

Reference

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