Comparison of serum thiol-disulphide homeostasis and total antioxidant-oxidant levels between exudative age-related macular degeneration patients and healthy subjects.

PURPOSE: The purpose of the study was to calculate serum total oxidant status (TOS), total antioxidant status (TAS), and dynamic thiol-disulphide (T-D) homeostasis in patients with age-related macular degeneration (AMD), and compare the results with healthy individuals. METHODS: Thirty-three exudative AMD patients and 33 healthy controls were included in this case-control study. Participants' serum TAS and TOS levels were measured. In addition, total thiol (TT), native thiol (NT), and disulphide (DS) concentrations were assessed using a novel automated method of measurement. RESULTS: In comparison with the control group, serum TAS, TT, and NT levels were found to be significantly lower (p < 0.0001, p = 0.004, p = 0.003, respectively) and TOS levels were detected higher (p = 0.032) in AMD patients. Serum DS levels were elevated in the AMD patient group, but the difference was not statistically significant (p = 0.219). DS/TT and DS/NT ratios were significantly higher (p = 0.012, p = 0.013, respectively) in AMD patients. A positive correlation was found between TT and NT (p < 0.0001) in AMD group. CONCLUSIONS: Serum TOS levels are higher, TAS levels are lower, and the T-D balance is shifted to the DS bond side in AMD patients. These results suggest that increased oxidative stress and decreased antioxidant levels may play a role in AMD progression. Further studies are needed to confirm the pathophysiologic role of T-D homeostasis in AMD.

Intraocular pressure in infants and its association with hormonal changes with vaginal birth versus cesarean section.

To investigate cord arterial blood sample and the relationship between birth stress and intraocular pressure in infants at 5 min after delivery. The IOP measurements were taken using Tonopen-Avia tonometer to 158 newborns (158 eyes) at 5th min after birth, in a university hospital. Cord blood was collected within 3 min after delivery. Intraocular pressure, gender, gestation period, mode of delivery, and birth weight of newborns were noted from medical records. Sixty-two babies were delivered by normal vaginal delivery (NVD) and 96 by cesarian section (C/S). Mean IOP of NVD and C/S groups were 19.56 ± 3.84 and 17.42 ± 3.50, respectively. There was significant difference of mean IOP between two groups. (p < 0.001) There were significant differences between two groups regarding APGAR score (p < 0.001) and cord blood adrenaline (p = 0.003), noradrenaline (p = 0.008), and cortisol (p < 0.001) levels. There was no difference between infant corneal thickness measurements (p = 0.698). In correlation analyses, there is a strong negative correlation between the labor type and postpartum measurements except corneal thickness. Correlation analyses of the 5th min intraocular pressure of the groups individually revealed significant correlation in the NVD group. The conclusion is that the intraocular pressure of newborn infants was higher in NVD delivery compare to C/S. Blood hormonal changes in different anesthesia types and physical stress was thought as the main reason of this result.

Comparison of retinal nerve fiber layer and macular thickness measurements with Stratus OCT and OPKO/OTI OCT devices in healthy subjects.

AIM: To compare retinal nerve fiber layer (RNFL) and macular thickness measurements obtained with the Stratus optical coherence tomography (OCT) and OPKO/OTI OCT devices. METHODS: Included in the study were 59 eyes of 30 participants. All measurements for each eye were done on the same day with both devices. Student's paired t-tests were used to compare the central macular thickness and RNFL measurements of the Stratus OCT and OPKO/OTI OCT. Pearson correlation was used to assess the relationship between the devices. Coefficient of variation (COV) was calculated to assess intersession repeatability. RESULTS: Using both the Stratus OCT and OPKO/OTI OCT, respectively, the measured mean average RNFL thicknesses were 98.9±11.1 µm and 115.1±9.6 µm (P=0.001), and the measured mean central retinal thicknesses (CRT) were 196.2±18.8 µm and 204.5±21.1 µm (P<0.001). Measured by the two devices, the RNFL thickness values were correlated in all quadrants, as were the retinal thickness values except the inferior outer sector. COV for average RNFL and CRT thickness were 2.9% and 4.6% for Stratus OCT, and 2.1% and 4.2% for OPKO/OTI OCT, respectively. CONCLUSION: We found good reproducibility of RNFL and retina thickness measurements for both Stratus OCT and OPKO/OTI OCT devices. However, even though the two OCT systems provided statistically correlated results, the values for both RNFL and macular thickness were statistically different. RNFL and macular thickness measurements with the OPKO/OTI OCT were higher than that of the Stratus OCT; therefore, the two OCT systems cannot be used interchangeably for the measurements of RNFL and macular thickness.

Effects of polyquaternium- and benzalkonium-chloride-preserved travoprost on ocular surfaces: an impression cytology study.

PURPOSE: To compare the toxicity effect of polyquaternium (PQ) and benzalkonium chloride (BAK) preservation of travoprost on the ocular surface. METHODS: This prospective study included 44 eyes of 44 patients with newly diagnosed glaucoma. Twenty-two patients used PQ-preserved travoprost (PQ group) and 22 patients used BAK-preserved travoprost (BAK group). To investigate the effect on the ocular surface, conjunctival impression cytology (IC) was performed at baseline and the 1- and 6-month follow-up visits. Additionally, the ocular surface disease index (OSDI) questionnaire, Schirmer I test, and tear break-up time (TBUT) measurement were administered at baseline, and at 1-, 3-, and 6-month follow-up visits. RESULTS: While both groups showed statistically significant IC grade increases at 1 and 6 months when compared with baseline measurements, IC grades were significantly higher for patients using PQ-preserved travoprost compared with patients using BAK-preserved travoprost. The Schirmer I test and TBUT scores were not statistically significant between group 1 and BAK group at baseline and at 1-, 3-, and 6-month visits (P>0.05). OSDI scores did not statistically differ at baseline and the 1-month measurements between the 2 groups (P>0.05), but the 3- and 6-month OSDI scores were significantly higher for BAK group (P=0.001). Differences in OSDI and Schirmer I test scores were statistically significant at 1, 3, and 6 months in both groups as compared with baseline values (P<0.05). Statistically significant differences in the TBUT scores were seen for both groups at 3 and 6 months, while BAK group, but not PQ group, had insignificant score differences at 1 month as compared with baseline values of PQ group (P=0.083). CONCLUSION: PQ-preserved travoprost was found to be safer and better-tolerated than BAK-preserved travoprost. PQ-preserved travoprost provided better ocular surface comfort, and therefore a better patient experience, which would likely result in higher treatment compliance.