The short answer: two reliable baseline VF’s then one every six months within the first year for newly diagnosed glaucoma patients.
Says who?
A study published in Ophthalmology examined over 1,000 eyes of glaucomatous patients. These patients had at least five visual fields performed within a two to five year period. Using statistical data from these fields, specifically the mean deviation (MD), the authors asked the question, how long does it take to detect progression on visual fields?
Using their protocol of two baseline fields then one every six months, they found that 80% of eyes with a rapid rate of MD loss (of −2 dB/year, for example) would be detected after 2.5-3 years.
One interesting finding was that additional testing did not “decrease the time required to detect progression and might, on the other hand, increase the chance of false-positive detections”.
It should also be said that patients with more advanced visual field loss or presenting with mild damage at a younger age may require more frequent visual field testing in clinical practice.
The take home: two reliable visual field tests at baseline followed by one test every six months within the first year of follow-up may be a reliable and cost-effective monitoring schedule for newly diagnosed glaucoma patients.