What is Visual Field Index (VFI)? - Glaucoma Glossary

The Visual Field Index is a global summary metric that quantifies the overall percentage of normal vision a patient retains, adjusted for age, ranging from 100% (perfect) to 0% (perimetrically blind).

What it means for the patient

This is the clearest "report card" number for your glaucoma. If your VFI is 95%, it means you have retained 95% of your functional vision. The goal of all treatment is to keep this number from dropping over your lifetime.

Clinical significance

Continuous linear regression charting of VFI slopes provides a highly actionable velocity metric. A slope of -1.5%/year compared to a patient life expectancy allows precise prediction of whether functional blindness will occur in the patient's lifetime.

How it is tracked

The VFI slope is the core actuarial metric plotted directly against demographic life expectancy tables within the Glaucoma One intelligent dashboard.