And as we take a moment to review the different types of instrumentation you come across when you’re reviewing the visual fields test, a couple of things to take note are; you may have something that looks similar to a Humphrey fields analyzer or an Octopus visual fields analyzer, those are going to be visual field tests that require you to change lenses and they have a trial lens holder and the varying brightness of lights are actually in a machine or device that’s kind of like a box setting and there is kind of a circular component to it of this device. And it also requires you to change out the trial lenses. I think also what we need to take a look at is it does include a screen that is usually attached to it that allows you to follow the patient's testing as you move along.
Other types of visual field analyzers are similar to that of the Humphreys Matrix or Humphreys FDT. Which allows the patients to keep their current correction on throughout the duration of the test.
Another method of visual field testing would be a virtual reality, it allows a portable device to be utilized throughout the duration of the test. A couple of key things to evaluate as you’re looking at all of these things, one does it require you to change out any lenses, is any patching involved, and also you know, typically there will be some type of remote to use with visual fields test. So, take a look at all of those things. I would highly recommend and keep referring you back to looking at your manuals of your instruments that you have in your office.
During the preliminary testing, in order to check the visual fields, those four quadrants that we discussed earlier, that can also be checked through the utilization of confrontation. So that will check when the patient is able to identify those. So, we’ll review that in our next segment of how to do the procedure for each one of those, at least give you a general overview of each one of those.