V.P. FOKIN, E.G. SOLODKOVA, V.A. BREEV

Volgograd branch of S. Fyodorov Eye Microsurgery Federal State Institution, 80 Im. Zemlyachki St., Volgograd, Russian Federation, 400138

 Fokin V.P. ― D. Sc. (medicine), Professor, Director, e-mail: mntk@isee.ru

Solodkova E.G. ― PhD (medicine), Head of the Department of Correction of Refraction Anomalies, Eye Surgeon, e-mail: mntk@isee.ru

Breev V.A. ― Eye Surgeon of the Department of Correction of Refraction Anomalies, e-mail: mntk@isee.ru

Thirty nine cases (22 patients, 39 eyes) of postoperative keratectasia after LASIK operations out of 46,500 keratorefractional excimer laser operations were detected, which is 0.0008%. In the study were detected as follows: 10 eyes (25.6%) with the initial high degree myopia (HDM), 18 eyes (46.1%) with pachymetry values less than 510 μm, 6 eyes (15.4%) with a combination of HDM and low values of pachymetry. 16 eyes (41.0%) had keratometry values more than 45.0 dioptres. The predictive index of keratectasias, reflecting the percentage of altered tissue, was more than 40.0% observed in 6 eyes (15.4%) with high degree myopia and low pachymetry values. The values of predictive index of keratectasias from 35.0 to 40.0% were obtained in 20 eyes (51.3%). To prevent the development of keratectactic changes in the cornea after keratorefractive excimer laser surgery shall be conducted the topography studies of the corneal posterior surface, optical coherent mapping of the epithelial layer, investigation of the biomechanical properties of the cornea, improvement of the technique for calculating the excimer laser operations to reduce the predictive index of keratectasias and preserve the maximum possible thickness of the residual stroma, also give the patients at risk of developing keratectasias accurate recommendations for lifestyle management.

Key words: keratectasia, excimer laser keratorefractive surgery.

(For citation: Fokin V.P., Solodkova E.G., Breev V.A. Assessment of risk factors for the development of keratectasia after excimer laser keratorefractive surgery. Practical Medicine. 2018)

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