Correlation of Visual Field Changes With Optical Coherence Tomography in Primary Open Angle Glaucoma

PURPOSE: To detect morphological changes in Optic Nerve Head (ONH), macula and Retinal nerve fibre layer (RNFL) using spectral domain optical coherence tomography (SDOCT) and to correlate them with functional loss (Visual field changes) using 24-2 and 10-2 standard automated perimetry in Primary open angle glaucoma patients. RESULTS: Mean value of 90D cup to disc ratio (CDR) of study subjects was 0.64 ± 0.13 with median (25th-75th percentile) of 0.7(0.6-0.7). Mean value of average RNFL thickness(microns), superior quadrant thickness (micron), inferior quadrant thickness (micron), nasal quadrant thickness (micron) and temporal quadrant thickness (micron) of study subjects was 62.35 ± 14.43, 77.96 ± 14.29, 81.41 ± 22.84, 51.33 ± 21.14 and 50.71 ± 17.71 with median(25th-75th percentile) of 63(52-75), 78(66.25-89), 81.5(64.25-93.75), 54(46-63) and 50.5(39-57.75) respectively. Mean value of average macular thickness (micron), macular GCL-IPL thickness -Superior quadrant (micron) and macular GCL-IPL thickness -Inferior quadrant (micron) of study subjects was 65.6 ± 11.7, 76.49 ± 11.63 and 76.76 ± 16.86 with median (25th-75th percentile) of 64(56-75), 75(67-87.75) and 75.5(65.25-93) respectively. Mean value of MD and PSD of study subjects was -7.34 ± 4.47 and 6.8 ± 3.11 with median (25th-75th percentile) of -7.65(-11--3.1) and 6.9(3.9-9.1) respectively. 57(41.3%) eyes had early glaucoma, 51(37%) eyes had moderate glaucoma and 30(21.7%) eyes had advanced glaucoma. CONCLUSION: In present study, ONH parameters (rim area), RNFL parameter (inferior quadrant thickness) and macula parameters (average macular GCLIPL thickness) showed statistically significant correlation with VF MD. Correlation between VF parameters i.e. MD and PSD with OCT parameters shown that there was a relation between Macular GCLIPL thickness ,RNFL thickness and ONH with the changes in the results of VF.