N.A. POZDEYEVA^1,2, M.V. SINITSYN¹, N.P. PASHTAYEV^1-3

¹Cheboksary branch of the S. Fyodorov Eye Microsurgery Federal State Institution, 10 Traktorostroiteley Pr., Cheboksary, Russian Federation, 428028

²Postgraduate Medical Institute, 3 Krasnaya Ploshchad’, Cheboksary, Russian Federation, 428032

³Chuvash State University named after I.N. Ulyanov, 15 Moskovskiy Pr., Cheboksary, Russian Federation, 428015

Pozdeyeva N.A. ― D. Med. Sc., Deputy Director on Research, Professor of a course in Ophthalmology, tel. (8352) 36-46-96, e-mail: [email protected]

Sinitsyn M.V. ― ophthalmologist,  e-mail: [email protected]

Pashtayev N.P. ― D. Med. Sc., Professor, Director of Cheboksary branch of the S. Fyodorov Eye Microsurgery Federal State Institution, Head of the course in Ophthalmology of Postgraduate Medical Institute of the Chuvash Republic, Head of the Department of Ophthalmology and Otolaryngology of Chuvash State University, tel. (8352) 36-46-88, e-mail: [email protected]

 The article presents a clinical and functional analysis of the efficiency of correction of residual irregular corneal astigmatism after intracorneal segments (ICS) implantation in patients with keratoconus (KC) of II-III stages using laser thermokeratoplasty (LTK). We had operated 7 people (7 eyes) with KC of II-III stages according to Amsler-Krumeich classification. All patients underwent LTK 6 months after the ICS implantation. The coagulation zones were staggered into 4 rows in an optical zone along a circle with a diameter of 5.0 to 8.5 mm in the projection of a weak corneal meridian according to keratotopogram. Intra- and postoperative complications were not observed. After the operation, visual acuity in all patients improved due to a decrease in corneal astigmatism and an increase in the regularity of the cornea in the central optical zone, as well as an increase in the biomechanical properties of the cornea in connection with the creation in it of an additional ring of stiffness from coagulants and an earlier ICS implantation. Thus, LTK is an effective and safe method of correction of residual corneal astigmatism after ICR implantation, and also increases the biomechanical properties of the weakened cornea in patients with KC of II-III stages.

Key words: laser thermokeratoplasty, keratoconus, intracorneal segment, irregular corneal astigmatism.

REFERENCES

1. Ambrosio K.J., Conso R.S., Luz A., Coca V.G. Corneal thickness spatial profile and corneal-volume distribution: tomographic indices to detect keratoconus. J. Cataract. Refract. Surg, 2006, no. 11, pp. 1951-1959.
2. Belin M.W., Khachikian S.S., Ambrosio R.J., Salomao M.Q. Keratoconus/Ectasia detection with the Oculus Pentacam: Belin/Ambrosio enchancedectasia display. Highlights of ophthalmology, 2007, no. 6, p. 2.
3. Pashtaev N.P., Pozdeeva N.A., Sinitsyn M.V., Shcheglova M.A. Comparative analysis of remote clinical and functional results of implantation of MyoRing intrastromal rings by standard and optimized technologies using a femtosecond laser in patients with keratoconus. Oftal’mokhirurgiya, 2017, no. 1, pp. 40-46 (in Russ.).
4. Suslikov S.V., Maslova N.A., Pashtaev N.P. Dynamics of visual functions and biomechanical properties of the cornea after laser thermokeratoplasty in patients with keratoconus. Oftal’mokhirurgiya, 2009, no. 4, pp. 4-10 (in Russ.).
5. Maslova N.A., Pashtaev N.P. Remote clinical and functional results after intrastromal keratoplasty using an IntraLaseFS femtosecond laser in patients with keratoconus. Oftal’mokhirurgiya, 2011, no. 1, pp. 62-66 (in Russ.).
6. Pashtaev N.P., Sinitsyn M.V., Pozdeeva N.A. Comparative analysis of clinical and functional results of femtoscopic implantation of intrastromal segments and MyoRing rings in patients with keratoconus. Oftal’mokhirurgiya, 2014, no. 3, pp. 35-41 (in Russ.).
7. Kubaloglu A., Cinar Y., Sari E.S., et al. Comparison of 2 intrastromal corneal ring segment models in the management of keratoconus. J. Cataract. Refract. Surg, 2010, no. 6, pp. 978-985.
8. Torquetti L., Ferrara G., Almeida F., et al. Intrastromal corneal ring segments implantation in patients with keratoconus: 10-year follow-up. J. Refract. Surg, 2014, no. 1, rr. 2-26.