What CDR is considered suspicious for glaucoma?

Vertical CDR >0.7 in isolation is suspicious; CDR >0.6 with asymmetry >0.2 between eyes warrants glaucoma workup; CDR must be interpreted with disc size (large discs normally have larger cups).

What is the ISNT rule in glaucoma?

Normal optic disc neuroretinal rim: Inferior > Superior > Nasal > Temporal in width; violation of the ISNT rule (thinning/notching of inferior or superior rim) is characteristic of glaucomatous damage and warrants OCT and VF testing.

What OCT RNFL thickness indicates glaucoma?

Average RNFL <80 μm is below 1st percentile in Cirrus OCT; sector-specific loss (inferior/superior outside red/yellow normative database) is more sensitive than average RNFL alone; asymmetry between eyes is also significant.

What disc hemorrhage significance in glaucoma?

Disc (Drance) hemorrhage is a significant sign of active glaucomatous damage and high mechanical stress on nerve fibers; associated with NTG, disc hemorrhage predicts future VF progression; modify treatment upon any hemorrhage observation.

What VF tests are used for glaucoma monitoring?

SAP (standard automated perimetry) using SITA-Standard or SITA-Fast 24-2 or 10-2 programs; VF mean deviation <-6 dB = moderate, < -12 dB = severe glaucoma; 2 or more measurements needed to confirm VF progression.

Cup-to-Disc Ratio Glaucoma Risk Assessment

Assesses cup-to-disc ratio for glaucoma risk stratification using vertical CDR, ISNT rule compliance, neuroretinal rim analysis, and peripapillary nerve fiber layer thickness guidance.

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