Stage 1: | OHT = elevated IOP exceeding 24 mm Hg on at least two occasions, or one single measurement of 30 mm Hg or more with a normal visual field and without glaucomatous cupping of the optic disc. |
Stage 2: | Glaucomatous disc cupping with normal visual field. |
Stage 3: | Glaucomatous disc cupping and one scotoma within 30°, and/or a nasal step or sector shaped defect in the periphery. |
Stage 4: | As in stage 3, but with the addition of a new scotoma within 30° in the opposite half of the visual field, or the creation of a breakthrough to the periphery. |
Stage 5: | As in stage 4, with the addition of a breakthrough to the periphery both upwards and downwards from the paracentral scotoma. |
Stage 6: | A small remnant of the central visual field plus a temporal remnant. |
Stage 7: | A temporal remnant, loss of central visual field (visual acuity 0.1 or less). |