What average corneal thickness does Goldmann's tonometry assume?

Goldmann's tonometry assumes an average corneal thickness of 520 micrometers (um). This is significant because the accuracy of intraocular pressure (IOP) measurements using Goldmann's applanation tonometer is influenced by the thickness of the cornea. A corneal thickness of 520 um represents a commonly accepted normative value for the average human cornea.

When the cornea is thicker than this assumed value, the measurement may underestimate the true IOP, while a thinner cornea may lead to overestimation. This assumption is critical for proper assessment and management of conditions like glaucoma.

Understanding this value is essential for practitioners, as adjustments may need to be made if a patient's corneal thickness deviates significantly from the normative average of 520 um. Thus, this figure is a foundational aspect of interpreting tonometric measurements accurately.