Relationship between visual field changes and optical coherence tomography measurements in advanced open-angle glaucoma

Abstract

Aim: To assess relationships between functional changes in visual field and structural changes in advanced open-angle glaucoma (OAG) found using spectral-domain optical coherence tomography (SD-OCT). Methods: Thirty-one eyes of 25 patients with OAG were included in this study. Besides the routine ophthalmological exam the patients underwent standard automated perimetry (SAP) (Humphrey Field Analyzer) and SD-OCT (RTVue–100) performed within 6 months. The global perimetric indices in the study group were as follows: mean deviation (MD) 12.33±6.18 dB and pattern standard deviation (PSD) 9.17±3.41 dB. The relationship between OCT measurements and MD and PSD was evaluated by correlation analysis (Pearson’s correlation coefficient) and regression analysis (linear and nonlinear regression models). Results: Thickness measurements of the lower halves of ganglion cell complex (GCC) and retinal nerve fiber layer by two scanning protocols (ONH and 3.45) showed these to be thinner than the upper halves, but the difference failed to reach statistical significance. The correlations between global indices MD/PSD and most of the analysed quantitative OCT measurements were moderate (r in the range between 0.3 and 0.6). The correlation between MD and GCC showed nonlinear cubic regression (R2=0.417, P=0.004). Good correlation was found between MD and GLV (R2=0.383; P=0.008). Linear regression (P<0.05) was found only between MD and Cup area (R2=0.175, P=0.024) and between MD and RNFL by 3.45 protocol (R2=0.131, P=0.045). Conclusion: Nonlinear regressive models appear to be more appropriate in the assessment of the correlations between functional and structural changes in eyes with advanced glaucoma. The correlations we found were moderate.

Associations of Ganglion Cell-Inner Plexiform Layer and Optic Nerve Head Parameters with Visual Field Sensitivity in Advanced Glaucoma

“…Changes in ONH parameters, such as the rim area and C:D ratio (average and vertical), were small but statistically significant in advanced glaucoma [15]. Kostianeva et al [45] found significant correlations of the rim area and C:D ratio with the HFA 30-2 VF MD in advanced open-angle glaucoma. Lee et al [46] evaluated correlations between neuroretinal rim area rates of change and VF rates of change in glaucoma patients with a wide range of glaucoma severity and found that a decreased rim area correlated with a worse MD and the mean threshold sensitivities of fast components of VF decay in moderate/advanced glaucoma.…”

Comparison of the Structure-Function Relationship Between Advanced Primary Open Angle Glaucoma and Normal Tension Glaucoma

“…4,[8][9][10] Although attempts have been made to identify the associations between structural measures and functional defects in glaucoma, the structurefunction relationship in advanced glaucoma has not been thoroughly investigated. 8,[11][12][13] Recently, we evaluated the relationship between the central VF and macular parameters in advanced glaucoma patients whose peripapillary RNFL thickness reached the measurement floor and found that the nasal macular region showed statistically significant relationships with the central VF. In addition, we found some differences in the structure-function relationship between primary open angle glaucoma (POAG) and normal-tension glaucoma (NTG) patients.…”

“…Specifically, the strength of the structure-function relationship is known to be weaker in the early stage of glaucoma and reaches its peak in the moderate stage, after which it gradually decreases as the disease progresses to the advanced stage 4,8–10. Although attempts have been made to identify the associations between structural measures and functional defects in glaucoma, the structure-function relationship in advanced glaucoma has not been thoroughly investigated 8,11–13. Recently, we evaluated the relationship between the central VF and macular parameters in advanced glaucoma patients whose peripapillary RNFL thickness reached the measurement floor and found that the nasal macular region showed statistically significant relationships with the central VF.…”