Corneal epithelial thickness mapping in modern laser refractive surgery: diagnostic and prognostic significance

Purpose: to systematize current data on the diagnostic and clinical significance of corneal epithelial thickness mapping (ETM) in laser refractive surgery, particularly its role in detecting ectasia, surgical planning, and assessment of postoperative epithelial remodeling. Materials and methods. The study focused on modern methods for assessing the thickness and spatial distribution of the corneal epithelium. A review and analysis of scientific publications on the use of very-high-frequency ultrasound and spectral-domain optical coherence tomography for epithelial thickness mapping in patients with keratoconus, corneal ectasia, and after keratorefractive procedures was performed. Results. ETM complements corneal tomography in the detection of early keratoconus and cases with suspicious topographic findings. The most characteristic feature is the «doughnut» pattern of epithelial remodeling. The method also enables assessment of postoperative epithelial changes following LASIK, SMILE, and photorefractive keratectomy and may be considered when planning selected refractive procedures. Conclusion. ETM has practical value as an adjunctive method for preoperative screening and postoperative monitoring; however, it cannot replace corneal tomography.

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