Possibilities of scleral lenses for visual rehabilitation of patients with corneal scars

Purpose. To analyze the efficacy and safety of SCL in patients with corneal cicatricial changes and other concomitant conditions. Material and мethods. The study included 19 patients (20 eyes) with cicatricial deformity of the cornea of various etiology, who were fitted with scleral contact lenses. Results and discussions. The use of SCL is possible in post-traumatic pathology, such as corneoscleral scars with or without aphakia, as well as after keratitis with an outcome in cicatricial deformity, cicatricial changes after a burn. A significant increase in visual acuity compared with spectacle correction has been proven. Depending on the topography of the scar, it is possible to select scleral lenses such as Oblate and Prolate, as well as with different versions of the support zone: both toric and quadratic. Conclusion. Scleral lenses can be successfully used for optical correction in patients with cicatricial changes in the cornea and other concomitant post-traumatic conditions of ineffectiveness of other methods of visual rehabilitation. Key words: cornea, lenses, vision correction, contact lenses, visual rehabilitation, scleral lenses, corneal scars, post-traumatic astigmatism, aphakia, keratitis, toric lenses, quadratic lenses, astigmatism, irregular cornea, regular cornea, regular astigmatism, irregular cornea, irregular astigmatism, prolate, oblate.

Keratectasias and modern methods of their treatment

The review article provides non-surgical (spectacle and contact correction, ultraviolet corneal crosslinking) and surgical methods (corneal transplantation, intrastromal implantation of segments and rings) for the treatment of keratoectasias and, in particular, keratoconus. The authors present their own original developments of scientists from the Ufa Research Institute of Eye Diseases in the field of cross-linking and various types of keratoplasty, as well as promising areas of clinical research on the combined treatment of keratectasias: cross-linking in combination with LASIK, intrastromal introduction of segments and rings. Key words: cornea, keratectasias, keratoconus, non-surgical and surgical methods of treatment.

Morphological assessment of changes in the cornea of experimental animals after ultraviolet corneal cross-linking

Purpose. To investigate the dynamics of morphological changes in the rat cornea after its ultraviolet cross-linking using various photosensitizer solutions. Material and methods. Studies were conducted on 20 rats in three groups. In the first group, 0.1% Riboflavin solution was used for saturation, in the second – 0.1% Riboflavin and 20% dextran; the third – intact (control). A UV cross-linking model (370 nm, 3 mW/cm2, 10 min) with corneal deepithelization with a diameter of 3 mm was used. Histomaterial processing was performed according to the standard procedure on the 3rd, 7th, and 30th days after surgery. Histological sections 1-4 microns thick were prepared on a rotary microtome RM 2145 (Leica Microsystems, Germany), stained with hematoxylin-eosin and using the van Gieson method. Light microscopy was performed using a LEICA DM 2500 microscope with a Leica DFC 450 digital camera (Leica Microsystems, Germany). Results. The main morphological changes in the rat cornea after UV cross-linking with 0.1% Riboflavin solution were associated with loosening of bundles of collagen fibers. This was caused by the development of stroma edema in the early postoperative period (3-7 days), which persisted up to 30 days of the experiment. A morphological feature of the use of Dextralink solution in corneal cross-linking is less pronounced stroma disfoliation, which is associated with the dehydrating effect of dextran. In both groups, a decrease in the density of stroma keratocytes was found. Key words: cornea, ultraviolet corneal cross-linking, corneal morphology.

Prognostic and preventive role of various factors in corneal rejection after keratoplasty

The literature review is devoted to the analysis of modern publications on the immunological and pathogenetic mechanisms of transplanted corneal rejection, risk factors, predictors and methods of the prevention of this complication. The prevention of corneal rejection is challenging. Currently, there is no single algorithm for the predicting methods of the corneal graft rejection, so further research in this area is needed. Purpose. To assemble the current data on immunological and non-immunological predictors of postoperative complications after keratoplasty. The analysis of modern publications on the immunological and pathogenetic mechanisms of corneal transplant rejection, risk factors, predictors and methods of prevention of this complication is presented. The databases used were CyberLeninka, PubMed, and Medline. The focus was on the publications of the last 10 years. Conclusion. The data presented in the review make it possible to identify signs of corneal transplant rejection and to determine treatment in a timely manner, as well as to implement methods for preventing these complications. Key words: cornea, keratoplasty, keratograft, rejection, cytokines, ocular immune privilege.