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Purpose: To investigate the role of oxidative stress and antioxidant system in the etiopathogenesis of pseudoexfoliation and progression of pseudoexfoliation syndrome to glaucoma., Material and Method: A total of 20 patients with pseudoexfoliation syndrome, 20 with pseudoexfoliation glaucoma, 20 with primary open-angle glaucoma, and 20 without pseudoexfoliation and glaucoma as a control group, who underwent cataract or glaucoma surgery between December 2020 and March 2021 in the Health Sciences University Beyoğlu Eye Training and Research Hospital, 80 patients were included in the study. Best corrected visual acuity (BCVA), intraocular pressure with applanation tonometry, detailed anterior and posterior segment examinations with biomicroscopy were performed in all patients included in the study. Approximately 0.1 cc of anterior chamber fluid was taken from all patients at the beginning of surgery. Total Oxidant Status (TOS) and Total Antioxidant Status (TAS) levels were measured by keeping the samples taken in the deep freezer of the cornea bank at -80 degrees, transferring them with cold chain transport rules, and examining them with automatic measurement method in the laboratories of the Medical Biochemistry Department of the University of Health Sciences. Oxidative Stress Index (OSI) value was calculated to measure the degree of oxidative stress., Results: TAS averages of the control and POAG groups were found to be statistically significantly higher than the PES and PEG groups (p = 0.0001, p = 0.0001). No significant difference was observed between the other groups (p > 0.05). The TOS averages of the control and POAG groups were found to be statistically significantly lower than the PES and PEG groups (p = 0.003, p = 0.0001; p = 0.01, p = 0.001), no statistically significant difference was observed between the other groups (p > 0.05). The OSI mean of the control and POAG groups was found to be statistically significantly lower than the PES and PEG groups (p = 0.001, p = 0.0001; p = 0.002, p = 0.0001), no statistically significant difference was observed between the other groups (p > 0.05)., Conclusion: Increased TOS and OSI and decreased TAS levels in the aqueous humour of patients with PES and PEG suggest that increased oxidative stress and decreased antioxidative defense system play a role in the etiopathogenesis of the disease.

Purpose: The aim of this study is to evaluate the variability of central retinal thickness asymmetry in healthy Caucasian adults with the posterior pole asymmetry analysis to serve as a reference., Methods: In total, 404 eyes of 202 subjects who aged between 18 and 80 years, who had no ocular pathology, were included in this cross-sectional observational study. Retinal thickness maps with posterior pole asymmetry analysis mode were taken with the optical coherence tomography (SPECTRALIS SD-OCT; Heidelberg Engineering). Superior and inferior hemifields were divided into five zones resembling to the strategy in Glaucoma Hemifield Test. Mean retinal thickness in each of the five zones was compared with the thickness of the corresponding zone in each eye (paired-samples t-test), and differences in retinal thickness (DRT1-5) and ganglion cell layer thickness between reciprocal locations were measured. Differences in retinal thickness values of two eyes of each subject were also compared (independent-samples t-test)., Results: The intra-eye asymmetry was statistically significant in zones 4 and 5. The highest mean intraocular differences in retinal thickness were 5.8 µm (zone 5) in all eyes, 5.8 µm (zone 5) in the right eyes, and 5.9 µm (zones 4 and 5) in the left eyes. The only statistically significant interocular local differences in retinal thickness asymmetries were found in zone 3. The intraocular asymmetry in retinal thickness was found to be the lowest in zone 1. The differences of ganglion cell layer thickness (GCLTs) were not statistically significant., Conclusion: There were statistically significant physiological inter-eye asymmetry in zone 3 and intra-eye asymmetries in zones 4 and 5. These measurements must be considered during screening for glaucoma with posterior pole asymmetry analysis in the Caucasian population.

Purpose: To evaluate the effects of 2 different amounts of commonly used intravitreal agents on anterior segment morphology in conjunction with intraocular pressure (IOP) changes., Methods: Two groups of 46 patients who received intravitreal injection of bevacizumab (group 1, 0.05 mL) or bevacizumab-triamcinolone acetate (TA) combination (group 2, 0.1 mL) were included in this prospective study. All patients underwent anterior segment optical coherence tomography 
(AS-OCT) imaging with Visante OCT and IOP measurement before and at 5 minutes, 1 hour, and 3 hours after injection. Anterior chamber depth (ACD), angle-opening distance (AOD 500-750), trabecular-iris space area (TISA 500-750), and anterior chamber angle (ACA) were measured. Results were compared between groups and measurement time points., Results: The mean change in IOP showed significant difference between baseline and first measurements after the injection in group 1 and group 2 (p = 0.012, p = 0.008, respectively). There was a statistically significant difference from baseline in ACD at the first and second measurements in group 2 (p = 0.005, p = 0.018, respectively). All angle parameters showed insignificant decrease from baseline at all measurement time points in both groups (p>0.05 for each). The difference of angle parameters after injection was not statistically significant between the groups (p>0.05 for each)., Conclusion: Intravitreal injection of bevacizumab (0.05 mL) or bevacizumab-TA combination (0.1 mL) caused a change in anterior segment configuration determined by AS-OCT. The changes in anterior chamber parameters returned to baseline values with the normalization of IOP values after the first few minutes of injection.

Purpose: The pupil diameter under low ambient illumination is diagnostically valuable for refractive surgery. The aim of study was to compare the NeurOptics® Pupillometer, Sirius®, and Ocular Wavefront Analyser® in determining scotopic pupil diameter., Materials and Methods: A total of 96 eyes of 48 subjects were included. The scotopic pupil size was measured with 3 instruments and the measurements repeated following instillations of 1% cyclopentolate. Agreement between the instruments was assessed., Results: The mean measurement obtained by Sirius was significantly larger than Ocular Wavefront Analyser and NeurOptics. The Ocular Wavefront Analyser measured significantly smaller than the others. The mean cycloplegic pupillary diameters (7.73±0.70 mm with NeurOptics, 7.42±0.45 mm with Ocular Wavefront Analyser, and 8.06±0.76 mm with Sirius) were significantly different obtained by 3 instruments (p<0.001, for each; one-way analysis of variance and paired t tests)., Conclusions: The differences between measured pupil diameters with or without cycloplegia obtained by the NeurOptics, Sirius, and Ocular Wavefront Analyser were significant and have unacceptable levels of disagreement. These results may not be related to illumination and accommodation only, but also to measurement algorithms and technical differences of the devices.

Purpose: To evaluate the safety and efficacy of piggybacking with the HumanOptics Add-On intraocular lens (IOL) to correct pseudophakic refractive errors., Materials and Methods: Ten eyes of 10 patients with pseudophakic refractive errors were included in this study. All patients were targeted for a range of refraction -0.50 to +0.50 D. Uncorrected and corrected distance visual acuities (UDVA and CDVA, respectively), endothelial cell count (ECC), anterior chamber depth (ACD), the distance between intraocular lenses, and contrast sensitivity measurements under mesopic, scotopic, and scotopic with glare conditions were evaluated preoperatively and postoperatively., Results: The mean age of the patients was 54±27 years (range 4-78). Mean follow-up time was 10.5±1.36 months (range 6-15 months). Mean diopters of implanted Add-On IOLs were -1.4±6.9 (range -12 to +9 D). Mean preoperative and postoperative UDVA was 0.133±0.12 and 0.73±0.27, respectively (p=0.0001); mean preoperative and postoperative CDVA were 0.77±0.26 and 0.79±0.27, respectively (p=0.066). Mean preoperative and postoperative ACD were 3.87±0.91 mm vs 3.58±1.05 mm, respectively (p=0.343); mean inter-IOL distance was 0.53±0.08 mm. Mean preoperative and postoperative ECC were 2455±302 and 2426±294, respectively (p=0.55). All patients were within the targeted refractive range of -0.50 D to +0.50 D. No complications were observed during the operations or postoperative follow-up period., Conclusions: Piggybacking with the Add-On IOL is a safe, efficient, and reliable technique to correct pseudophakic refractive errors.

Purpose: To investigate biomechanical parameters of the cornea measured with ocular response analyzer (ORA) in myopic eyes with high axial length and the relationship between these parameters and axial length (AL)., Methods: A total of 165 eyes of 165 consecutive patients were included. Eyes with AL greater than 26 mm were named group 1 and eyes with AL shorter than 26 mm were named group 2. Axial length and keratometric values were measured by intraocular lens (IOL) Master optical biometry. Metrics of corneal biomechanical properties, including corneal hysteresis (CH) and corneal resistance factor (CRF), were measured with the ORA. The ORA also determined the values of intraocular pressure (IOPg) and corneal compensated IOP (IOPcc)., Results: The mean age of total subjects was 43.0 ± 15.6 years. Eighty-three eyes were included in group 1; 82 eyes were included in group 2. The CH and CRF of group 1 were significantly lower than group 2. The IOPcc was significantly higher in group 1 than group 2. When group 1 and group 2 were combined for analysis, CH was negatively correlated with age. Both CH and CRF were significantly correlated with SE. However, CH and CRF were negatively correlated with AL. Also, there was significant correlation between AL and IOPcc (p<0.05)., Conclusions: Highly myopic eyes showed decreased CH and CRF. As the AL increased the IOPcc also increased and the CH decreased. We conclude that the biomechanical properties of the cornea change with elongation of the eye and this may have an impact on IOP measurement.