Introduction: In the field of ophthalmology, laser technology is used in many basic and clinical disciplines and specialities. It has played an important role in promoting the development of ophthalmology. Aim: This article is designed to review the evolution of laser technology in refractive surgeries in ophthalmology, mainly focusing on the characteristics of the excimer laser applied in corneal refractive surgery. Methods: This article was performed based on a literature review and Internet search through scientific databases such as PubMed, Scopus, Web of Science and Google Scholar. Result: The literature on excimer laser technology addresses the technical and physical aspects of excimer lasers including types, characteristics and commercially available lasers on the market. Conclusion: The conclusion on this forum aims to help understand the benefits of excimer laser use in ophthalmology, with focus on correction of refractive errors.

Introduction:Marcus Gunn syndrome is a rare phenomenon with very less number of cases reported in literature. It may be congenital or acquired.Aim:The aim of this case report was to report the clinical characteristics of Marcus Gunn patient from our Clinic.Case report:A comprehensive opthalmologic examination, CDVA (corrected distance visual acuity), fundus examination and photography, was conducted in Marcus Gunn patient. Clinical findings of patient presented as - chin positioned slightly upwards, extraocular motility normal on both eyes, cover test with normal findings, pupillary examination normal on both eyes. Left upper eyelid was in a lower position than the right one. On right eye, rima interpalpebrarum was 9 mm with upgaze of 13mm. On the left eye, rima interpalpebrarum was 5 mm with upgaze of 6 mm, and with open mouth, left rima interpalpebrarum was 10 mm. Visual acuity on both eyes was 1.0. Cycloplegic refraction on both eyes was +0,75 diopters (D), and Lang test was normal. In the differential diagnosis of patients with ptosis, Marcus Gunn jaw winking syndrome should be considered especially if it improves during feeding, sucking, chewing, smiling or any kind of mouth movement. In case of ptosis always do the jaw test. Have the infant bottle-feed. An older child can chew gum. Have the patient open the mouth, move the jaw from side to side, or protrude the jaw forward.Conclusion:Address first to treatment of any amblyopia if present - eyeglasses, patching etc., or strabismus. Think twice before deciding to operate.

Aim: To evaluate safety and efficacy of Laser in situ Keratomileusis (LASIK) procedure for the correction of high hypermetropia. Methods: Retrospective study of 160 patients (266 eyes) who underwent LASIK procedure for the correction of hypermetropia between +3.00 and +7.00 diopters(D) and cylinder up to 2.00D from January 2013 and August 2015. All ablations were performed with Wavelight Allegretto Eye-Q400Hzexcimer laser (Alcon, Forth Worth, TX, USA) with aberration free module and were centered on a corneal vertex. All flaps were made with Moria M2 (Moria, Antony, France) mechanical microkeratome (90μm head). Preoperative and postoperative uncorrected and corrected distant visual acuity (UDVA, CDVA), spherical equivalent (SE) and a berrometry for 5mm pupil were measured. Measurements were taken at 1 week, 1,3,6 and 12 months after the surgery. Wilcoxon Signed Ranks Test was used for statistical analysis. Results: Postoperative UDVA was lower than preoperative CDVA at 1 week( p =0.001), at 1 month there was no difference ( p =0.099), and at 3,6 and 12 months UDVA was better ( p <0.0001). Preoperative SE was 4.69±1.20D (+3.75 to +7.50D). At 1 week SE was 0.03±0.67D (-0.50 to +0.63D), while at 1 year regressed to 0.58±0.56D (+0.25 to +0.88D). Sphere shifted from negative values targeted in treatment planning to compensate for regression to positive values. There was significant difference in SE at every time point ( p <0.0005). There was a significant increase in coma ( p <0.0001), trefoil ( p <0.0001, p =0.0006) and spherical aberration ( p =0.022, p =0.0052) at 1 week and 1 month postoperatively, without change throughout the rest of follow up. Conclusion: LASIK for high hypermetropia showed satisfactory results in postoperative refraction with reasonable regression without significant loss of lines of visual acuity. However, more test are necessary to asses optical quality.

Introduction: Keratoconus (KCN) is known to affect all ethnicities but its incidence exhibits geographical variability plausibly due to subclinical forms of the disease, differences in diagnostic methods and criteria, or differences in genetic variations in populations. Aim: To examine the prevalence of keratoconus among the refractive surgery population of Vojvodina, who underwent refractive surgery screening at Eye Clinic Svjetlost Novi Sad, Serbia from September 2018 to September 2019. This is a single-center study. Methods: Retrospective analysis of 876 patients who presented for refractive surgery evaluation. Corneal tomographers represent the gold standard in the detection and classification of corneal ectatic diseases and screening is an essential part of the preoperative diagnostics before any refractive surgery. The corneal tomographer used in this study was a Scheimpflug imaging device (Pentacam AXL, Oculus Optikgeräte GmbH, Wetzlar, Germany). The device was realigned before each measurement. Results: Out of a total number of patients, 619 (70,7%) were candidates for corneal refractive surgery procedure, and 257 patients (29.3%) were not. Out of 257 patients that were not candidates for the procedure 157 (61,0%) patients had thin corneas, high myopia/hypermetropia or had some retinal disease; 75 patients (29,1) were keratoconus suspect and 25 patients (9,7%) had keratoconus. KCN patients had a mean age of 29.5 ± 7.7 years, 18 patients (72.0%) were male and 7 patients were female (28%). Conclusion: The most cited annual incidence of KCN is 2 approximately 1 per 2,000. Recent data from the biggest Netherland study revealed many different epidemiological results which deprive keratoconus of the community of rare diseases. The incidence of keratoconus in Vojvodina refractive surgery population presented in our Clinic was 2.9%.

Introduction: The crosslinking (CXL) procedure using the standard Dresden protocol is established as the gold standard for the treatment of progressive keratoconus. Aim: The aim of this paper is to correlate the pachymetry and elevation back map (EBM) changes in the period from 3 to12 months of keratoconus patients after the CXL procedure. Methods: Forty-four eyes of 34 patients with keratoconus were analyzed after performed standard Dresden protocol CXL procedure. All of them underwent complete preoperative examination with a follow up of 12 months with a focus on pachymetry and EBM changes performed by Oculus Pentacam (Scheimpflug technology) analysis. Results: Pachymetry changed significantly in 12 months post cross-linking, especially in the first 6 months after which it slightly increased. Differences in EBM preoperatively and 12 months postoperatively were not statistically significant. Conclusion: Corneal pachymetry in keratoconus patients decreases after the CXL procedure. Differences in pachymetry preoperatively and 3, 6 and 12 months postoperatively were statistically significant, but the value of corneal thickness increased from the third month to 12 months post-op. Differences in EBM preoperatively and 12 months postoperatively were not still statistically significant, which is good, because the increase in elevation, as one of the signs of progression of the keratoconus-did not occur.