We created 280 sources on the hemisphere at visual field angles of −70° (temporal) to 70° (nasal) in steps of 0.5°.
An eye which is accompanied by a limitation in the fields of vision such that the widest diameter of the visual field subtends an angle no greater than 20 degrees shall be considered for purposes of the first sentence of this subsection as having a central visual acuity of 20/200 or less.
The ultrasound technique allows changes to be made to several parameters: depth of the visual field, the sweeping angle that defines the sample volume and the frame rate.
Table 1 presents the details of the population in this study.> -wrap-foot> *56 subjects with incomplete data were excluded from the analysis The IOP distribution of normal population was calculated by excluding data of subjects with definite glaucomatous visual field defects or angle closure.
POAG cases in this study were defined by the following criteria: the presence of glaucomatous optic neuropathy (defined as loss of neuroretinal rim with a vertical cup : disc ratio of >0.7 or an inter-eye asymmetry of >0.2 and/or notching attributable to glaucoma) with compatible visual field loss, open angles on gonioscopy, and absence of secondary causes of glaucomatous optic neuropathy.
VFL: visual field loss; PACG: primary angle closure glaucoma; POAG: primary open-angle glaucoma; NTG: normal tension glaucoma; LogMAR: logarithm of the minimum angle of resolution; HCVA: habitual corrected visual acuity; MD: mean defect of visual field; IOP: intraocular pressure.
BACKGROUND: Vascular phenomena are considered important to optic nerve and visual field progression in open-angle glaucoma (OAG).
Primary open-angle glaucoma (POAG) is defined as a chronic and progressive disease, characterized by acquired loss of optic fibers, glaucomatous disc progression, visual field changes, and open angles in the absence of known underlying cause.
Starting outside the animal's visual field, the stimulus travels an angle of 80 degrees in its visual field, and is then retracted along the same path.
Normal-tension glaucoma (NTG) is an optic neuropathy associated with a glaucomatous optic nerve head, progressive retinal nerve fiber layer thinning, characteristic visual field defects, open anterior chamber angle on gonioscopy, and a maximum intraocular pressure (IOP) below 21 mmHg [ 1].
