ABSTRACT
Background/aim: This study aimed to evaluate retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) thicknesses using spectral domain optical coherence tomography (SD-OCT) in both unilateral and bilateral exfoliation syndrome (XFS) patients Materials and methods: Twenty-four patients with unilateral XFS, 20 patients with bilateral XFS, and 23 healthy subjects were enrolled in this study. Eyes with XFS were compared with both fellow eyes and age-matched control subject eyes in terms of mean and segmental RNFL thickness and minimum, mean, and segmental GCC thickness. Results: In the bilateral XFS group, minimum GCC of the right eye (75.80 ± 11.6 µm) was significantly thinner compared with the right eyes of the control group (81.83 ± 6.6 µm) (P < 0.05). Also, superior RNFL was thinner in the right eye (106.90 ± 16.7 µm) compared with left eye (114.15 ± 18.1 µm) in the bilateral XFS group (P < 0.05). No significant differences in the unilateral XFS group were detected in GCC and RNFL analysis. Conclusion: Minimum GCC value may be the first parameter affected in the conversion of XFS to exfoliative glaucoma followed by RNFL changes.
Subject(s)
Exfoliation Syndrome/epidemiology , Exfoliation Syndrome/pathology , Nerve Fibers/pathology , Retinal Ganglion Cells/pathology , Aged , Case-Control Studies , Female , Humans , Male , Middle Aged , Tomography, Optical CoherenceABSTRACT
PURPOSE: To evaluate the repeatability of vessel density and superficial and deep foveal avascular zone measurements using optical coherence tomography angiography, and to specify a diurnal change range. METHODS: Forty-six eyes of 25 healthy individuals were included. Optical coherence tomography angiography measurements were planned for three consecutive sessions, with 3 hours in between them. AngioVue software of the RTVue XR Avanti was used. Superficial and deep retinal layer vessel density values, including the whole retina, fovea, and each parafoveal zone, were obtained from the software. The intraclass correlation, coefficient of variation, and coefficient of repeatability were calculated for each parameter. RESULTS: The whole image intraclass correlation value was 0.81 for the superficial and 0.86 for the deep layer among the three consecutive sessions. The smallest real difference (coefficient of repeatability) value of whole image measurements was 7.72% for the superficial and 9.84% for the deep retinal layer. Foveal avascular zone area intraclass correlation value was 0.97 for the superficial and 0.83 for the deep retinal layer. CONCLUSION: The optical coherence tomography angiography analysis provides quantitative data about the retinal microvasculature, which could be used to distinguish between normal and pathology. Changes in superficial vessel density >8% and deep vessel density >10% may be considered as real clinical change rather than variation.
