D.S. MALTSEV, E.V. KUDRYASHOVA, A.N. KULIKOV, A.Yu. MAREYCHEV

S.M. Kirov Military Medical Academy, 6 Akademik Lebedev Str., St. Petersburg, Russian Federation, 194044

  Maltsev D.S. ― Cand. Med. Sc., ophthalmologist of the Laser Surgery Department of Ophthalmology Clinic, e-mail: glaz.med@yandex.ru

Kudryashova E.V. ― Head of the Laser Surgery Department of Ophthalmology Clinic, e-mail: kudryashovaelen@yandex.ru

Kulikov A.N. ― D. Med. Sc., Head of the Ophthalmology Department, e-mail: alexey.kulikov@mail.ru

Mareychev A.Yu. ― resident doctor of the Laser Surgery Department of Ophthalmology Clinic, e-mail: mareychev@mail.ru

 Analysis was carried out of the correlation between epithelial and corneal thickness in normal subjects and in patients after laser keratomileusis (LASIK) in situ. The study included 83 healthy subjects (83 eyes) and 47 patients (93 eyes) who underwent LASIK. The patients were examined 1 day and 1 month after laser keratomileusis (LASIK) in situ. The examination was carried out using optical coherence tomography with Copernicus REVO device. The analysis included the thickness of the cornea and epithelium in the central zone without the tear film. We found positive correlation between corneal thickness and corneal epithelium thickness (r=0.53, p<0.001) with the normal epithelial-pachimetry coefficient (ECR) of 10.1±0.6%. One day postoperatively and one month postoperatively ECR was 12.5±1.0% and 13.8±1.9%, respectively. The area under curve for ECR as a diagnostic criterion for previously performed myopic LASIK was 0.996. In healthy subjects, corneal epithelium constitutes 10.1% of corneal thickness. The epithelial to corneal thickness ratio may serve as a reliable criterion allowing to figure out the fact of previously performed myopic LASIK.

Key words: cornea, corneal epithelium, corneal thickness,optical coherence tomography, LASIK

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