Structure-Function correlation between OCT and both Visual Field SITA Standard 24-2 and SITA Faster 24-2C

Abstract Purpose  Optical Coherence Tomography (OCT) is a powerful instrument to help clinicians detect and monitor the onset and progression of glaucoma.  The aim of this study is to evaluate structure-function correlations first step for a detailed mapping of the relationships between Humphrey visual field 24-2 SITA Standard and 24-2C SITA Faster sensitivities and measurements of retinal structure provided by Spectral Domain (SD)-OCT system (RTvue-100 Optovue).   Patients and Methods  Ninety-six eyes eyes of open-angle glaucoma patients (mean age 74.44 ± 10.02 years) were included in this retrospective observational study. Thickness values for superior and inferior retina, as well as average values, were recorded for both ganglion cell complex (GCC) and peripapillary retinal nerve fiber layer (RNFL). RNFL thickness was further evaluated along with twelve separate sectors. Point-wise correlations were then computed between each of these OCT measurements and the visual sensitivities at all visual field locations.  Results  Mild to moderate (p<0,05) correlations were observed between the peripapillary RNFL thicknesses and both the 24-2 and the 24-2C visual field regions. In particular, the most significant correlations (p<0.001) were found for the fibers of the upper and temporal sectors. Excellent (p<0.001) correlations were observed between the visual field regions and the GCC thicknesses and both the 24-2 and the 24-2C visual field regions. Central macula points tested with 24-2C SITA Faster were found to correlate well (p<0.001) with fibers in the superior, temporal, and inferior sectors of the RNFL. Excellent (p<0,001) correlations have also been found with the GCC thickness. Conclusion  The 10 additional points of the 24-2C SITA Faster allow for a more complete perimetric assessment of the glaucoma disease and, combined with the GCC and RNFL measurements, are therefore a promising parameter for glaucoma detection and monitoring.