J Korean Ophthalmol Soc.  2009 May;50(5):779-784. 10.3341/jkos.2009.50.5.779.

Confocal Microscopic Findings of Transplanted Cornea 10 Years After Penetrating Keratoplasty

• Kim NM
• Shin MK
• Kim SJ
• Lee JS

• KMID: 2212324
• DOI: http://doi.org/10.3341/jkos.2009.50.5.779

Abstract

PURPOSE:To examine the morphological characteristics of the transplanted cornea in patients who received penetrating keratoplasty at least 10 years previously prior. CASE SUMMERY: Each layer of the transplanted cornea of patients who received penetrating keratoplasty 10 years previously prior was examined with a confocal microscope (ConfoScan 4.1, Fortune Technology, Italy). Cross-sectioned corneal images of the corneal epithelium, Bowman's layer, stromal layer, Descement's membrane, and endothelium were evaluated and compared with the normal fellow other eye. A total of three eyes from three subjects between the ages of 60 and 70 years were examined. The epithelial cells had large cell borders, and a spindle shaped, and a highly reflective nucleus. The keratocytes were highly reflective and the density of keratocytes was lower than that in the normal cornea. The regenerated nerve fibers were markedly altered, as characterized by increased nerve tortuosity, reduced branching patterns, and shorter nerve lengths. In the endothelial cell layer, a bright nucleus, a reduced ratio of hexagonal cells, and several multinuclear cells were observed.
CONCLUSIONS
Even 10 years after penetrating keratoplasty, the entire transplanted cornea is morphologically different from the normal cornea.

Keyword

Confocal microscopy; Penetrating keratoplasty

MeSH Terms

Cornea
Dental Porcelain
Endothelial Cells
Endothelium
Epithelial Cells
Epithelium, Corneal
Eye
Humans
Keratoplasty, Penetrating
Membranes
Microscopy, Confocal
Nerve Fibers
Transplants
Dental Porcelain

Figure

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  Figure 1. Corneal epithelial layer images of normal human (A) and penetrating keratoplasty patient (B) digitalized directly from confocal microscopy through focusing scan (case 2). (A) normal epithelial cells. (B) abnormally elongated epithelial cells (arrow) were found in the cornea after PKP. The nucleus of epithelial cells was more prominent.

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  Figure 2. Corneal subbasal nerve plexus images of normal eye (A) and penetrating keratoplasty eye (B) digitalized directly from confocal microscopy through focusing scan (case 1). (A) normal subbasal nerve fibers. (B) abnormal subbasal nerve regeneration in the peripheral cornea after PKP. There were markedly increased nerve fiber tortuosity(arrows), beading, reduced branching pattern, and shorter nerve length.

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  Figure 3. Confocal microscopic images of 10 years after penetrating keratoplasty (case 2). All images are taken from a 60-year-old man (case 2). (A) normal anterior stroma. (B) activated keratocytes were apparent in anterior stroma. The hyper-reflectivity of activated keratocytes contributes to significant levels of corneal haze. Keratocytes with visible cytoplasm were prominent in the anterior part of the stroma. Reflective structures (arrows) represent the cytoplasmatic protrusions of an interconnected meshwork of keratocytes.

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  Figure 4. Confocal microscopic images of 10 years after penetrating keratoplasty (case 2). All images are taken from a 60-year-old man (case 2). (A) normal posterior stroma. (B) the keratocytes displayed irregular morphology and lower cell density than normal cornea. Because of corneal edema, hyporeflective folding lesions (arrows) were found on confocal microscopy.

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  Figure 5. Corneal endothelial images of normal eye (A) and penetrating keratoplasty eye (B) digitalized directly from confocal microscopy through focusing scan in the same patient (case 1). (A) Normal endothelial cell density (2,998 cell/mm2). (B) Endothelial cell density and hexagonal cell density were decreased after penetrating keratoplasty (PKP). Multinucleated cells (white arrows) were seen in a case of PKP. The endothelial cell density was decreased to lower than normal endothelial cell density (2,057 cell/mm2). Corneal guttae (hollow arrow) appeared as roundish hyporeflective images.

Reference

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