Why does CCT affect IOP readings?

Thicker corneas (>555 μm) overestimate true IOP; thinner corneas (<555 μm) underestimate. Correction: ΔT ≈ 0.7 mmHg per 10 μm deviation from 555 μm (Doughty-Zaman).

What is the normal range for IOP?

Normal IOP: 10–21 mmHg (Goldman tonometry, CCT ~555 μm). IOP >21 mmHg with glaucomatous optic neuropathy constitutes open-angle glaucoma.

Intraocular Pressure (IOP) Correction for CCT

Correct measured IOP for central corneal thickness (CCT) using the Ehlers, Goldman, and Doughty-Zaman formulas.

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Frequently Asked Questions

Why does CCT affect IOP readings?

What is the normal range for IOP?