Test Conditions in Macular Visual Field Testing in Glaucoma

The purpose of this study is to evaluate the suitable visual field (VF) test conditions (target size, test type, and eccentricity) for the macular region, we investigated the correlations between the ganglion cell layer (GCL) thickness and 6 VF test results.

We tested 32 eyes of patients (61.1±9.2 y) with preperimetric (6), early-stage (16), and moderate-stage (10) glaucoma. The VF tests included 3 SAP (the 10-2 HFA using SITA with target size III [HFA SITA (III)], full threshold with size III [HFA FULL (III)] and size I [HFA FULL (I)]) and 3 visual function-specific perimetry tests (the 10-2 SWAP, 10-2 flicker, and 10-2 Humphrey Matrix). The GCL and inner plexiform layer (GCL+IPL) thickness was measured by Spectral Domain Optical Coherence Tomography (SD-OCT) with a macular 7×7 mm cube scan (3D OCT-2000, Topcon). The coefficient of determination (r) for the correlation between visual sensitivity and the GCL+IPL thickness was calculated for each test at eccentricities 0 to 5 degrees, 5 to 7 degrees, and 7 to 10 degrees using linear and quadratic regressions.

All 6 tests showed the strongest correlation with the GCL+IPL thickness at 5 to 7 degrees. The respective r (linear) and R (quadratic) for HFA SITA (III), HFA FULL (III), HFA FULL (I), SWAP, Flicker, and Matrix were (0.40, 0.50), (0.43, 0.53), (0.44, 0.46), (0.51, 0.51), (0.33, 0.34), and (0.52, 0.52).

As compared with the frequently-used SAP with a size III, SAP with size I and the function-specific perimetry tests (especially the Matrix) could be more suitable for testing the macular region.