Journal of Clinical and Experimental Ophthalmology
Open Access
ISSN: 2155-9570
ISSN: 2155-9570
Azat Khalimov, Mukharram Bikbov, Liliya Khalimova and Emin Usubov
Ufa Eye Research Institute, Russia
Scientific Tracks Abstracts: J Clin Exp Ophthalmol
Aim: Collagen cross-linking (CXL) with UV-A irradiation 370 nm and 0.1% riboflavin stabilizes the pathological process in the cornea. Improvement of the standard UV-A corneal cross-linking resulted in accelerated and pulsed-light accelerated UV-A cross-linking. It is necessary to compare these UV cross-linking techniques to assess its efficacy. Methods: The experiments were carried out on 36 porcine eyes in 4 groups (8 porcine eyes each) ex vivo: 1st group â?? intact (control); 2nd group â?? standard UV-A corneal cross-linking (S-CXL) â?? 3 mW/cm2, 30 min; 3rd group â?? accelerated UV-A corneal cross-linking (A-CXL) â?? 18 mW/cm2, 5 min; 4th group â?? pulsed-light accelerated UV-A corneal cross-linking (Pl-ACXL) â?? 18 mW/cm2, 10 min, pulsed exposure (1 sec on/1 sec off). In all experimental groups Epi-Off, UV-A light 370 nm and 0.1% Riboflavin + 20% Dextran was used. The flaps from the cornea were stretched until they were completely ruptured using a universal tensile testing machine. Biomechanical properties were assessed by the force at rupture and the Young's modulus. Results: All investigated methods of UV-A cross-linking led to an increase in the force at rupture and the Young's modulus of the porcine corneas. Young's modulus increased: S-CXL by 98±12.1%, A-CXLâ??86±9.4% and Pl-A-CXLâ??89±10.2%. Ultimate tensile strength increased: S-CXL by 67.8±9.5%, A-CXL-55.3±7.2%, Pl-A-CXL-58±8.1%. The maximum results of biomechanical strength were obtained in the S-CXL group. However, statistically significant difference between standard, accelerated and pulsed-light accelerated UV-A corneal cross-linking was not obtained. Conclusions: Standard, accelerated and pulsed-light accelerated UV-A corneal cross linking increased the biomechanical properties of porcine corneas ex vivo and Young's modulus. Standard UV-A corneal cross-linking had slight advantage.