3.6 years ago

anonymous FitEyes member ♦ 1.1k

@member_31

I recently switched to a new Glaucoma Specialist because my present one is retiring soon. I had a 24-2 Visual Field test with the new doctor and there was a 3-4% difference (worsening) than the previous test results I've had for the past 3 years at my prior doctor's office.

However, I checked back on previous Visual Fields done 4-5 years ago at a different doctor's office, and they were almost identical to this new one I had recently.

I am considered a "reliable" test taker without many false positives/negatives, so can this small difference be chalked up to being on a different machine in a different office?

3.6 years ago

David 370

@davidventureconconau

Yes, my personal experience with four different Humphrey machines that are the exact same model, is that VFT results will differ between them. These days I try to ensure I'm always tested on the exact same machine. If you get a printout of your VFT results, the machine identifying numbers are at the bottom of the page. One time I thought I was being tested on the same machine in the same room as always but, when I checked the identifying numbers on the printout, it turned out the clinic (which uses three identical Humphrey machines) had switched machines. So don't rely on thinking it's the same machine in the same room - check the identifying numbers as well.

3.6 years ago

dlarochemd • 120

@dlarochemd

Yes. Don’t worry about it. Just repeat the vf in 6 months to have a new baseline between the two.

3.6 years ago

Yuri Vainshtein • 180

@yuri_vains

If you wear glasses, the technician will need to put lenses into Humphrey. So it all depends on him doing a good job, especially if you have astigmatism. Doing test in a mask could also affect results. I would like to add practical advice. Before the Humphrey test starts, you will see central light. If this central light is fuzzy/not sharp/not focused, be assertive and ask technician to correct lenses before he starts the test!