Novel retroillumination biomicroscopy method for assessing the quality of donor corneal tissue

Background. Corneal endothelial dystrophy is one of the most common indications for lamellar keratoplasty. Selection of donor corneal tissue that meets established quality standards is a key step in preoperative preparation. Therefore, the development of new, readily available, and low-cost methods for preoperative evaluation aimed at improving donor tissue assessment remains a relevant and clinically important task. Purpose: To evaluate the effectiveness of retroillumination biomicroscopy in detecting defects in donor corneal tissue compared with conventional slit-lamp biomicroscopy. Materials and methods. Fifty donor corneas were examined using retroillumination biomicroscopy and standard slit-lamp biomicroscopy to identify various corneal defects, including epithelial defects, corneal nerve fibers, corneal scars after radial keratotomy, corneal scars after refractive surgery (LASIK, FemtoLASIK), postoperative scars resulting from tunnel incisions and paracenteses, stromal defects, including opacities, stromal infi ltrates, and endothelial defects, including Descemet membrane folds and localized endothelial damage. Retroillumination biomicroscopy was performed by adding diffuse light sources behind the slit lamp. Results. In donor corneal tissue, retroillumination biomicroscopy allowed significantly more frequent detection of epithelial defects (p = 0.01), stromal changes (p = 0.04), and endothelial defects (p = 0.04) compared with conventional biomicroscopy. Corneal nerve fibers were detected in four cases using retroillumination biomicroscopy and were not identifi ed with slit-lamp biomicroscopy (p = 0.04). Scars after radial keratotomy were detected with the same frequency using both examination methods (p = 1.0). Conclusion. Retroillumination biomicroscopy allows defects in donor corneal tissue to be detected, visualized, and documented with greater accuracy than conventional biomicroscopy. Detection of defects in donor corneal tissue allows preoperative stratifi cation of tissue suitability for different types of keratoplasty.

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