Correlation Between Retinal Nerve Fiber Layer, Optic Nerve Head and Macular Parameters and Structure Function Relationship in Glaucoma.

Purpose: To evaluate correlation between visual field indices and spectral domain optical coherence tomography (SD-OCT) parameters and correlation among SD-OCT parameters to have a better understanding of role of SD-OCT parameters in clinical practice. Materials and Methods: This is a retrospective controlled clinical study. Three hundred forty-three eyes (91 healthy, 80 ocular hypertension, 97 preperimetric glaucoma and 75 early glaucoma eyes) were analyzed. Retinal nerve fiber layer (RNFL), macular, optic nerve head (ONH) parameters were measured with SD-OCT. Correlation between visual field indices and SD-OCT parameters and correlation among SD-OCT parameters were calculated. Results: Average RNFL showed the best correlation with both mean deviation (MD) (r = 0.624) and pattern standard deviation (PSD) (r = 0.614). Other RNFL parameters, ganglion cell complex (GCC) parameters and total retina (TR) parameters showed moderate correlation whereas outer retina (OR) and ONH parameters showed poor correlation with MD. Correlation between RNFL and GCC parameters was strong. Correlation between RNFL and TR parameters was moderate. Poor correlation were found between OR parameters and both RNFL and GCC parameters. Moderate correlation was found between average RNFL and both rim area and rim volume. Other correlations with ONH parameters were poor. Conclusion: Good structure function relationship is present between visual field indices and SD-OCT parameters like RNFL and GCC parameters. These parameters reflect the severity of glaucoma and can be used for glaucoma monitoring. TR and some ONH parameters like rim area and volume can give supplementary information to use in clinical practice. [ABSTRACT FROM AUTHOR]