What is Visual Field Test (Perimetry)? - Glaucoma Glossary

A visual field test is a subjective functional clinical exam that measures the full horizontal and vertical range and sensitivity of peripheral and central vision.

What it means for the patient

This is the "click the button when you see the flashing light" test. Because glaucoma slowly steals your peripheral (side) vision first, this test maps out exactly where you have blind spots that you might not even realize are there.

Clinical significance

Standard Automated Perimetry (SAP) is the cornerstone of functional glaucoma management. Iterative testing allows calculation of the rate of progression, which defines whether current therapeutic IOP targets are biologically sufficient.

How it is tracked

The Glaucoma One AI automatically extracts Mean Deviation (MD), Pattern Standard Deviation (PSD), and VFI from perimetry printouts to compute actuarial trajectories.