Macular thickness changes in glaucomatous optic neuropathy detected using optical coherence tomography

Objective: To correlate macular thickness and retinal nerve fiber layer (RNFL) thickness in normal and glaucomatous eyes using optical coherence tomography. Methods: Complete examination, automated achromatic perimetry, and optical coherence tomography of the peripapillary RNFL and macula were performed. Exclusion criteria were visual acuity of less than 20/40, diseases other than glaucoma, and unreliable automated achromatic perimetry. Macular thickness measurements were generated using 6 radial optical coherence tomographic scans (5.9 mm) centered on the fovea, and mean and quadrantic macular thickness values were calculated. Results: Fifty-nine eyes of 59 patients (29 normal and 30 glaucomatous) were enrolled (mean ± SD age, 56.7 ± 20.3 years; range, 20-91 years). All eyes with glaucoma had associated visual field loss (mean ± SD mean defect, -8.4 ± 5.8 dB). Mean macular thickness was significantly associated with visual field mean defect (R² = 0.47; P<.001), pattern standard deviation (R² = 0.32; P<.001), and mean RNFL thickness (R²=0.38;P<.001). In glaucomatous eyes with visual field loss localized to 1 hemifield (n = 11), mean ± SD macular thickness in the quadrant associated with the field defect (277 ± 28 pm) was significantly less (P=.005) than in the unaffected quadrant (286 ± 27 pm). Mean RNFL thickness in the affected quadrant (89 ± 53 pm) was significantly thinner (P=.009) than in the unaffected quadrant (121 ± 39 pm). Main Outcome Measures: Mean total and quadrantic macular and RNFL thickness measurements. Conclusions: Macular thickness changes are well correlated with changes in visual function and RNFL structure in glaucoma and may be a surrogate indicator of retinal ganglion cell loss.