Purpose:
To evaluate perimetric cumulative probabilities for the 5% 10% 15% and 20% normal probability levels in eyes whose optic nerves were determined to be normal in minimal risk subjects, suspicious of glaucomatous changes, exhibiting glaucomatous optic neuropathy, and demonstrating glaucomatous damage.
Methods:
A normative database consisting of 305 subjects between the ages of 10 and 92 was used to generate cumulative sensitivity probabilities (0 to 100 percentile), adjusted to a median age of 45 years. The number of visual field locations that had sensitivities below the 5, 10, 15 and 20 percentiles were determined for 212 eyes of normal control subjects (N), 134 eyes of ocular hypertensives with normal visual fields and optic discs (OH), 87 eyes of glaucoma suspects with normal visual fields and glaucomatous optic neuropathies (S), and 42 eyes of patients with glaucomatous visual field loss and optic neuropathies (GL).
Results:
The figure below shows the number of visual field locations (mean, s.d.) for the 4 groups at the 5% (upper left), 10% (upper right), 15% (lower left) and 20% (lower right) probability levels. For the probability levels of 5,10, 15 and 20 percentile, there was a significant difference in the number of locations outside of these normal probability values as a function of the groups (Kruskal Wallis test, p< 0.0002 for all comparisons). Paired comparisons among the groups indicated that for all probability levels, there was no significant difference in the number of locations between the N and OH eyes, the N and S eyes, and the OH and S eyes, with the exception of the 1% level, where the N and OH eyes demonstrated a significant difference. For all probability levels, there were significant differences between the number of locations for the N and G eyes, the OH and G eyes and the S and G eyes.
Conclusions:
Our findings indicate that perimetric continuous scale probability plots reveal significant visual field differences among the continuum of normal to glaucoma groups.
Keywords: perimetry • visual fields • optic disc