PIROGOV’S PROTOCOL FOR ULTRAVIOLET CROSS-LINKING OF CORNEAL COLLAGEN IN COMBINATION WITH PERSONALIZED TRANSEPITHELIAL PHOTOREFRACTIVE KERATECTOMY FOR THE TREATMENT OF KERATOCONUS STAGES I-II

Purpose: to evaluate the efficacy and safety of our proposed method for treating keratoconus, including in patients with a corneal thickness of less than 450 microns, using corneal collagen UV crosslinking in combination with personalized transepithelial photorefractive keratectomy (Pirogov protocol).

Material and methods. A total of 60 patients (60 eyes) with progressive keratoconus stages I-II were examined. The first group consisted of 30 patients who underwent the standard Dresden UV crosslinking protocol, the second group consisted of 30 patients who underwent simultaneous personalized photorefractive keratectomy (PRK) with UV crosslinking according to the Pirogov protocol. All patients underwent visometry, refractometry, keratometry, keratopachymetry, keratotopography and optical coherence tomography (OCT) of the cornea before, after treatment and after 1, 3, 6, 12 and 24 months.

Results. In the group of patients operated on according to the Pirogov protocol, after surgery, a reliable (p<0.05) increase in uncorrected and best-corrected visual acuity (UCVA and BCVA) was observed after 1 month. after surgery relative to the initial values (before surgery – 0.11±0.1 and 0.53±0.22; after 1 month – 0.48±0.27 and 0.75±0.2, respectively), improvement of refractive indices (spherical equivalent of refraction decreased from -5.08±0.20 D to -1.04±1.56 D after 1 month) and keratotopographic corneal indices (KCI, KSI, ESI of the anterior corneal surface, SAI, SRI), the values of which remained stable during 2 years of observation. Similar parameters of the control group did not statistically change during the entire observation period.

Conclusion. The developed method of one-stage combined surgery of UV crosslinking of the cornea with personalized PRK on the excimer laser “Microscan Visum” demonstrated high efficiency and safety in the treatment of progressive keratoconus stages I-II.

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