Table 1.

Grading standard of visual field defect of glaucoma.

Category	Name	Main characteristic	Subtypes
1	Clear VF	Only relative defects.
2	Mild VF defect	Spot-like, stroke-like, or arcuate absolute defects, having no connection to the blind spot.	Nasal step defect; Paracentral scotoma defect; Temporal wedge defect
3	Moderate VF defect	Arcuate absolute defects already connected to the blind spot, with or without a nasal break-through into the periphery.	Partial arcuate defect; Arcuate defect; Altitudinal defect
4	Severe VF defect	Extensive ring-shaped or half ring-shaped defects, with a central island of sensitivity maintained.	Double arcuate defect; Tubular vision
5	Diffuse VF defect	Central island collapse, with only the temporal visual field area remaining.	Diffuse defect; Total visual loss

VF, visual field.