[Cup-to-disk ratio asymmetry: diagnostic value in glaucoma]

Area of Science:

• Ophthalmology
• Optometry
• Glaucoma research

Context:

• Glaucoma diagnosis relies on detecting structural and functional damage.
• Cup-to-disk ratio asymmetry is a key indicator of potential glaucomatous changes.
• Intraocular pressure (IOP) is a primary risk factor for glaucoma progression.

Purpose:

• To evaluate visual field abnormalities in suspected glaucoma patients with asymmetric cup-to-disk ratios.
• To correlate structural damage (cup-to-disk ratio) with functional deficits detected by perimetry.
• To investigate the utility of short wavelength automated perimetry (SWAP) in identifying early glaucomatous damage.

Summary:

• The study included 22 hypertensive eyes from 11 subjects with a cup-to-disk ratio difference exceeding 2/10.
• Conventional automated perimetry showed no significant inter-eye differences.
• Short wavelength automated perimetry (SWAP) revealed significantly lower average sensitivity in eyes with larger cup-to-disk ratios.
• Retinal nerve fiber layer (RNFL) studies indicated a higher defect rate in eyes with greater cup-to-disk ratios.
• Intraocular pressure (IOP) differences were statistically significant (1.23 mmHg, p<0.05).

Impact:

• Lateral cup-to-disk ratio differences signify structural glaucomatous damage linked to IOP.
• SWAP effectively detects functional visual field loss associated with structural glaucomatous damage.
• This research aids in understanding the relationship between structural asymmetry and functional impairment in glaucoma detection.