Browsing by Author "Pajic, Bojan (7801351067)"

Purpose: Pterygium is a common lesion affecting the population in countries with high levels of ultraviolet exposure. The final shape of a pterygium is the result of a growth pattern, which remains poorly understood. This manuscript provides a mathematical analysis as a tool to determine the shape of human pterygia. Materials and methods: Eighteen patients, all affected by nasal unilateral pterygia, were randomly selected from our patient database independently of sex, origin, or race. We included all primary or recurrent pterygia with signs of proliferation, dry eye, and induction of astigmatism. Pseudopterygia were excluded from this study. Pterygia were outlined and analyzed mathematically using a Cartesian coordinate system with two axes (X, Y) and five accurate landmarks of the pterygium. Results: In 13 patients (72%), the shape of the pterygia was hyperbolic and in five patients (28%), the shape was rather elliptical. Conclusion: This analysis gives a highly accurate mathematical description of the shape of human pterygia. This might help to better assess the clinical results and outcome of the great variety of therapeutic approaches concerning these lesions. © 2016 Pajic et al.

Purpose: To evaluate the participation of proinflammatory cytokines in the acute phase of corneal wound-healing response after excimer laser treatment. Methods: The study included 68 myopic eyes up to -3.0 diopters divided into two groups: 1) eyes treated with laser in situ keratomileusis (LASIK) (n=31) and 2) eyes treated with photorefractive keratectomy (PRK) (n=37). Each group was then divided into three subgroups based on tear sampling times: before (0 hours), 1 hour after, and 24 hours after treatment. The tear fluid was sampled from lower lateral tear meniscus using a cellulose microsurgical sponge. The levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, and IL-8 in tear fluid were determined by flow cytometry method. Results: Statistical significance was observed in the concentrations of TNF-α (P=0.0421) and IL-1β (P=0.0225) between samples collected 1 and 24 hours after PRK treatment in favor of samples collected 1 hour after treatment. IL-6 concentration changes showed a significant increase in the PRK group in both time intervals following treatment compared to pretreatment (0 hour/1 hour, P=0.0031; 0 hour/24 hours, P=0.0059). For IL-8 concentrations, significant differences were observed between control and experimental groups in samples collected 1 hour after LASIK and 1 hour after PRK treatment (P < 0.001 for both groups), and IL-8 concentrations between control and experimental groups in samples collected 24 hours after LASIK and 24 hours after PRK treatment were greater after PRK treatment (P=0.0005). Comparison of average concentration values of proinflammatory cytokines in all the tested samples between LASIK and PRK groups showed significantly higher levels of IL-1β in the LASIK group 24 hours after treatment (P=0.0134), and of IL-6 in the PRK group 24 hours after treatment (P=0.0031). Conclusion: The acute phase of corneal wound healing after excimer laser treatment is defined by an intensive inflammatory response. After PRK treatment, there were increased concentrations of TNF-α and IL-1β in tear samples 1 hour after treatment, IL-6, 1 and 24 hours after treatment, and IL-8, 1 and 24 hours after treatment. After LASIK treatment, there were increased concentrations of IL-8 in tear samples 1 hour after treatment and IL-1β, 24 hours after treatment. Both PRK and LASIK methods are characterized with a significant inflammatory response. However, tear findings following PRK method showed more intensive inflammatory response than the findings after LASIK method. © 2016 Resan et al.