CHANGES SPATIAL CONTRAST SENSITIVITY OF THE EYE AFTER REFRACTIVE SURGERY IN PATIENTS WITH MYOPIA LOW AND MODERATE DEGREE

Aim. The aim of the study is to compare changes in contrast sensitivity in patients with mild to moderate myopia after keratorefractive interventions using the SMILE, FemtoLASIK and PRK techniques.

Material and methods. The SMILE group consisted of 36 eyes with spherical refraction -3,6±1,6 dpt, the FemtoLASIK group consisted of 34 eyes with spherical refraction -3,4±1,5 dptr and the PRK group of 36 eyes with spherical refraction -3,6±1,5 dptr. The Zebra visocontrastometry program, version 3.02 (Astroinform SPE, Russia), was used to investigate spatial contrast sensitivity (CS). The study was performed before and 1 month after keratorefractive intervention.

Results. Analysis of the comparison between the preoperative CS level and the 1 month after keratorefractive intervention in SMILE group patients revealed a statistically significant CS decrease at high frequencies in the range 11,3 cycle/deg (р  =  0,01) and 16 cycle/deg (р = 0,005), in PRK group patients revealed a statistically significant CS decrease at high frequencies in the range 11,3 cycle/deg (р = 0,003), 16 cycle/deg (р = 0,002). In the FemtoLASIK group changes in spatial CS were not statistically significant (p>0.05).

Conclusion. FemtoLASIK allows us to preserve eye contrast sensitivity, i.e. does not lead to its significant decrease.

1. Foster PJ, Jiang Y Epidemiology of myopia. Eye (Lond) 2014;28(2):202–208.

2. Holden BA, Fricke TR, Wilson DA, et al. Global Prevalence of Myopia and High Myopia and Temporal Trends from 2000 through 2050. Ophthalmology. 2016;123(5):1036–1042.

3. Eskina E.N., Shamshinova A.M., Belozerov A.E. Contrast sensitivity in various refractive errors before and after photorefractive keratectomy // Clinical ophthalmology. – 2001. – Vol. 2, No. 2. – Pp. 75-79.

4. Beisenbayeva B.S., Tuletova A.S. Indicators of contrast sensitivity of eyes in students. Fedorov Readings: Collection of Abstracts. Moscow, 2011, p. 218.

5. Koskin S. A., Boyko E. V., Sobolev A. F., and Shelepin Yu. E. Mechanisms of Recognition of Contour “Disappearing” Optotypes // Russian Physiological Journal named after I. M. Sechenov. 2005. V. 91. No. 10. P. 1080–1090.

6. Koskin S. A., Shelepin Yu. E. Vizokontrastometriya // Modern Ophthalmology / Ed. V. F. Danilichev. SPb.: Publishing House “Peter”. 2000. Chapter 5. Pp. 195–209.

7. Tatanova O.Yu, Sorokin E.L., Research of the initial state of spatial contrast sensitivity in patients with myopic refraction before planning photorefractive surgeries.// Practical medicine -2018, No. 3- p. 171-173.

8. Pershin K.B., Ovechkin I.G., Pashinova N.F. et al. Professional criteria for restoring vision after photorefractive surgery, Proceedings of the International Symposium “Myopia, Refractive and Oculomotor Disorders” – Moscow, 2001, pp. 255-256.

9. Pershin K.B., Ovechkin I.G., Prokofiev A.B. et al. Dynamics of frequencycontrast characteristics of the visual system after performing photorefractive keratectomy in myopia of weak degrees.// Theoretical and clinical research as a basis for medical and surgical treatment of eye injuries. Abstracts of reports of the scientific and practical conference. – M. – 2000 – P. 172.

10. Semchishen A.V., Seminogov V.N., Semchishen V.A. The role of corneal roughness in the contrast sensitivity of vision after photorefractive operations. Clinical Medicine Almanac, 2008, pp. 150-154

11. Sekundo W, Gertnere J, Bertelmann T, Solomatin I. One-year refractive results, contrast sensitivity, high-order aberrations and complications after myopic small-incision lenticule extraction (ReLEx SMILE). Graefes Arch Clin Exp Ophthalmol. 2014 May;252(5):837-43.

12. Tan DK, Tay WT, Chan C, Tan DT, Mehta JS. Postoperative ocular higherorder aberrations and contrast sensitivity: femtosecond lenticule extraction versus pseudo small-incision lenticule extraction. J Cataract Refract Surg. 2015 Mar;41(3):623-34.