The accurate diagnosis of keratoconus, especially in its early stages of development, allows one to utilise timely and proper treatment strategies for slowing the progression of the disease and provide visual rehabilitation. Various keratometry indices and classifications for quantifying the severity of keratoconus have been developed. Today, many of them involve the use of the latest methods of computer processing and data analysis. The main purpose of this work was to develop a machine-learning-based algorithm to precisely determine the stage of keratoconus, allowing optimal management of patients with this disease. A multicentre retrospective study was carried out to obtain a database of patients with keratoconus and to use machine-learning techniques such as principal component analysis and clustering. The created program allows for us to distinguish between a normal state; preclinical keratoconus; and stages 1, 2, 3 and 4 of the disease, with an accuracy in terms of the AUC of 0.95 to 1.00 based on keratotopographer readings, relative to the adapted Amsler–Krumeich algorithm. The predicted stage and additional diagnostic criteria were then used to create a standardised keratoconus management algorithm. We also developed a web-based interface for the algorithm, providing us the opportunity to use the software in a clinical environment.

Purpose. Evaluation of the impact of the developed intracorneal gel stained implants for keratopigmentation based on various materials on the donor human cornea during organotypic cultivation. Material and methods. Three experimental samples of intracorneal gel stained implants were investigated: sample 1 based on sodium hyaluronate with organic pigment, sample 2 based on collagen hydrolyzate with inorganic pigment, and sample 3 based on hydroxypropyl methylcellulose (HPMC) with organic pigment. To determine the toxicity of the studied implants the apoptosis of keratocytes was determined in cryostat sections of the cornea. The method of immunohistochemistry was used to study apoptosis. Scanning electron microscopy was used to visualize the corneal structures in the presence of implants. Results. During the investigation we showed that a gel implant based on a collagen hydrolyzate and a pigment with an inorganic toner (28% in the composition) causes a weak expression of the initiator proteins of apoptosis Caspasa 8 and Cytochrome C, and there is no expression of the BAX and effector proteins Caspasa 3/7. It was revealed that samples No. 1 and No. 3 undergo partial dissolution and washout from the intrastromal tunnel, sample No. 2 based on collagen hydrolyzate has a dense structure and remains in the corneal tunnel throughout the entire cultivation period, for at least 7 days, which is showed using an electron-scanning microscopy. The proposed collagen hydrolyzate gel implant can be considered compact and non-toxic. Conclusion. As a result of organotypic cultivation for 7 days showed the best results intracorneal colored implant № 2 based hydrolyzate of collagen and inorganic toner. Intracorneal colored implant based on collagen hydrolyzate has a more compact and dense structure than the accompanying experimental samples. Key words: keratopigmentation, aniridia, intracorneal colored implant.

Purpose. Analyze of the long-term results of treatment of patients with progressive keratoconus initial stages performed according to the developed algorithm. Material and methods. Clinical studies were carried out on the basis of a retrospective analysis of three comparison groups, depending on the tactics of surgery. Group 1 consisted of 843 patients (1186 eyes) with progression of keratoconus who underwent crosslinking. Group 2 consisted of 1185 patients (1343 eyes) who underwent intrastromal keratoplasty with implantation of corneal segments (ISKP with implantation of RS) with a mechanical (1007 eyes) or femtolaser (336 eyes) method. Group 3 consisted of 912 patients (1270 eyes), these patients underwent combined treatment – ISKP+UV crosslinking. The observation was carried out for 10 years. Results. As a result of the observation of patients for 10 years from the moment of UV crosslinking, an increase in UCVA and BCVA was revealed 10 years after surgery by 0.33±0.05 and 0.2±0.04, respectively. There was a significant increase in the central thickness of the cornea, on average by 12.75±0.08µm after 10 years. When analyzing the results of the observation of group 2, an increase in UCVA and BCVA was observed by 3–6 months after MS implantation. Keratometry indices (Kmax) decreased by an average of 3.5±1.3 diopters after 10 years. There was an increase in the central corneal thickness by 19.25±2.2µm after 10 years. As a result of the observation of patients for 15 months after the combined treatment (UV-crosslinking+ISCP), an increase in UCVA and BCVA was revealed by 0.17±0.10 and 0.25±15, respectively. Keratometry indices (Kmax) decreased by an average of 4.1±0.9 diopters after 15 months. There was an increase in the central corneal thickness by an average of 15±6.2µm after 15 months. Conclusion. Our research has shown that after 6 years there is no need to repeat UV crosslinking. With the correct location of the corneal segments, the progression of ectasia stops, and the UCVA and BCVA increase. Differences were revealed in the dynamics of the postoperative course in patients with combined UV crosslinking and implantation of corneal segments, which is obviously associated with their mutual effect on the ectasized cornea. In order to improve the quality of life of patients with the initial stages of keratoconus, these methods of treating keratectasias can be used in wide clinical practice without the threat of a decrease in clinical and functional results over a long period of time. Key words: keratoconus, classification, algorithm, crosslinking, corneal segment