Purpose:
To evaluate the influence of age-related macular degeneration (AMD) on retinal nerve fiber layer thickness (RNFLT), optic disc and inner macular retinal thickness parameters measured with Fourier-domain optical tomography (RTVue-OCT) in non-glaucomatous eyes.
Methods:
One non-glaucomatous eye of 79 Caucasian persons was imaged. This comprised 25 healthy eyes, 19 eyes with early/intermediate AMD (geographic atrophy excluded), 16 eyes with subfoveal choroidal neovascularisation (CNV) and 19 CNV eyes after intravitreal antiangiogenic treatment (CNV-anti-VEGF).
Results:
Compared to the age-matched controls, no difference in any RNFLT and optic disc parameter was seen for any AMD group. The average macular thickness parameters did not differ between the controls and the AMD groups (ANOVA, p>0.05). In contrast, all pattern-based Ganglion Cell Complex (GCC) parameters were significantly higher (more abnormal) in the CNV and CNV-anti-VEGF group than in the control eyes (Mann-Whitney test, Bonferroni correction, p<0.001). For GCC Focal Loss Volume (FLV), the only pattern-based parameter classified by the software, the frequency of "borderline" and "outside normal limits" classifications, was significantly greater in each AMD group than in the control group (Chi-square test, Bonferroni correction, p≤ 0.03). Inner retinal segmentation errors occurred in 0%, 42.1%, 100% and 89.5% of the control, drusen, CNV and CNV-anti-VEGF eyes, respectively (Chi square test, p<0.001).
Conclusions:
In non-glaucomatous eyes, AMD significantly influences the pattern-based inner macular thickness parameters of the RTVue-OCT and the software-provided classification of GCC FLV, thus a detailed examination of the macula is necessary before an abnormal GCC parameter is considered to be a sign of glaucoma.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • nerve fiber layer • age-related macular degeneration