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Purpose: To quantify normative corneal optical density (COD) values of healthy individuals and to investigate alterations in the COD in relation to their ocular and demographic characteristics., Study Design: Prospective, cross-sectional, and observational., Methods: In total, 588 eyes from 588 healthy participants with clear corneas were consecutively enrolled. Corneal densitometry values expressed in standardized grayscale units (GSU) from different corneal layers and zones obtained using the rotating Pentacam Scheimpflug system were analyzed., Results: The mean (SD) COD over the 12-mm diameter area was 14.4 ± 2.74 GSU. A significant positive correlation was found between the participants' age and the total COD (r = 0.756, P < .001). No significant differences were found between males and females with respect to COD (P = .51). No significant correlation was found between the COD measurements and refractive error, pachymetry, and keratometry (P > .05 for all comparisons). On the other hand, COD was negatively correlated with white-to-white (WTW) corneal diameter (r = - 0.415, P < .001). Moreover, the WTW corneal diameter was correlated with the COD in any zone and layer of the cornea (P < .05 for all comparisons)., Conclusions: Wide variations in COD can be detected even in corneas deemed clinically clear. Age and corneal diameter that seem to influence corneal transparency should be taken into account when evaluating corneal backscatter.

Purpose: To establish the total oxidant status (TOS), total antioxidant capacity (TAC) and oxidative stress index (OSI) of the aqueous humour in patients presenting exfoliation syndrome (EXS) without glaucoma., Methods: The TOS, TAC and OSI of the aqueous humour of patients with EXS (group 1, n = 17) and patients without EXS (group 2, n = 25) who underwent cataract surgery were evaluated. Samples were measured spectrophotometrically using a colourimetric method. The Mann-Whitney U, independent-samples t tests, Pearson correlation and analysis of covariance tests were used in the statistical analyses., Results: The mean TOS in group 1 and 2 patients was 57.6 ± 32.4 and 30.4 ± 22.6 mmol/L, respectively, which is a statistically significant difference (p = 0.001). The mean TAC level in group 1 and 2 patients was 2.3 ± 0.7 and 2.5 ± 0.7 mmol/L, respectively, and although TAC was decreased in group 1 relative to group 2, the difference was not statistically significant (p = 0.55). The mean OSI in group 1 and 2 patients was 27.4 ± 17.1 and 12.5 ± 8.3 mmol/L, respectively, with the mean OSI level statistically higher in group 1 (p = 0.03)., Conclusion: Our findings provide evidence that the aqueous humour of EXS patients is characterised by increased oxidative stress and a disturbed oxidant/antioxidant balance. The increased oxidative stress and decreased levels of antioxidants in ocular fluids of EXS patients may play a significant role in the pathogenesis and complications of EXS.

Purpose: To evaluate optic nerve head (ONH) characteristics in patients with exfoliation syndrome (EXS)., Methods: This was a cross-sectional, observational study in which 73 eyes from 73 patients with EXS and 93 eyes from 93 age-matched healthy subjects who met the inclusion criteria were included. Topographic measurements of the ONH and peripapillary retinal nerve fiber layer (RNFL) thickness were performed by confocal scanning laser ophthalmoscopy, using a Heidelberg retina tomograph. Outcomes of interest were studied by Student t test and chi-squared test., Results: EXS patients and age-matched controls did not differ in ONH parameters. Nevertheless, the mean cup depth and height variation contour values were higher in the normal subjects (P = 0.07, P = 0.056, respectively). Mean RNFL thickness was 0.22 +/- 0.06 mm in the EXS group and 0.26 +/- 0.06 mm in the control group, (P = 0.001). Likewise, the RNFL cross-sectional area was significantly lower in exfoliative eyes (1.16 +/- 0.35 mm(2)) than in those of the control group (1.31 +/- 0.33 mm(2)) (P = 0.006)., Conclusions: No significant differences in ONH parameters between EXS patients and age-matched healthy subjects were observed; however, RNFL measurements in eyes with EXS showed lower values.