Visual field trend

About this calculator

Enter serial Humphrey visual field results for one test pattern to see the trend over time, or the change from first to last test when there are fewer than five tests over two years.

What you need

• The date and MD or VFI of each test
• The test pattern (24-2, 30-2 or 10-2), with all tests on the same pattern and strategy

How it is calculated

Each test date is converted to years from the first test. The trend is an ordinary least-squares line of the result against time. Its 95% confidence interval uses the standard error of the slope (residual variance with n − 2 degrees of freedom) and the two-sided Student t value. The trend is shown only with at least 5 included tests spanning at least 2 years; shorter series show the change from the first to the last test.

What the result can and cannot tell you

For MD, a more negative number means more field loss; for VFI, a lower percentage does. Cataract, the learning effect of early tests, tiredness and changes in treatment all affect results, and MD conventions differ between machines. The tool does not predict future field loss; your eye doctor decides whether the field is changing.

References

1. Prediction of glaucomatous visual field loss by extrapolation of linear trends. JAMA Ophthalmology
2. Netra Eye Institute: Glaucoma

Related

• Eye pressure reduction
• Ocular perfusion pressure
• Eye pressure fluctuation
• Glaucoma guide
• All eye calculators

For information only. These tools explain numbers and do not replace an eye examination or your eye doctor’s advice. Values you enter stay in your browser.