Personal Experience With Visual Field Testing

By Douwebergsma from nl, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=1806609

Why do you need a visual field test?   

The linked article explains the purpose of the test, and certainly if you need to have it done, get it done. But I have comments to make about such tests, solely based upon my personal experience as a veteran visual field test-taker.

To be honest, I do not have a high opinion of these tests.  They are much too subjective for my tastes, and, in my personal experience, prone to artifacts and a lack of reproducibility. I note that a number of factors independent of actual eye problems affect results in my case, such as fatigue and the quality and experience of the person administering the test.  As those of you who have taken such tests know, you have to look at a fixed point, and then click a button when you see spots of light - some bright, some faint - projected on the screen.  While the bright spots are easy to see, the faint ones are difficult, especially for someone tired, sleepy, or being subjected to distractions.  Among the possible distractions is having your head moved around during the test because the person administering the test did not set you up correctly to begin with.  Or, perhaps, the person administering the test is talking to someone, in person or on the phone, or some other noises occur.  A remember one incident that took place many years ago, when I was taking the test in a darkened room, and I was hearing noises suggesting that the women administering the test was standing behind me and changing her clothes!  

I also note that when "problems" are found in my case - problems that (so far) end up being not reproduced - they are almost always with the second eye tested (you test one eye at a time) - suggesting fatigue, distraction, etc. are affecting the results.  The test, particularly the longer versions given on some of the larger and more complex machines, can be long and tedious and by the time you are doing the second eye, things become difficult.  And, as I said, some of the spots are very, very faint.

What happens then is that you are told you may have a problem, and then a repeat test is scheduled in several months time, making you wait all that time to find out whether the problem is real or simply due to test conditions.  

I also wonder how relevant a test like this is to real-life conditions where a normal visual field is important.  Yes, I understand that a more stringent test may be useful to catch problems at their very early stages - and "better safe than sorry" may be a reasonable approach here.  But, still, I wonder - if there is such an overlap between findings indicative of real problems and findings resulting from simple fatigue, lack of attention, distraction, etc. then the test may be sub-optimal.

Eye doctors tell the patients that we need to deal with the test as is until something better comes along.  The problem is I've been taking these tests for nearly 40 years (!!!) and I haven't seen any real change or improvement in all that time.  There seems to be an attitude of "it works well enough, why bother to change it," and that causes stress to patients, at least it does for me.  

At minimum, for the time being, I think some protocol needs to be put in place so that a new aberrant result - if it is small enough and specific enough - can be retested at the same visit. Considering how long some doctors make you sit in the patient chair before seeing you after you take the visual field, I would think that any eye strain and fatigue from the first test of that day would be long gone and you could be quickly re-tested on the eye(s) that presented the problem.  That's the short-term solution.  The long-term solution is for a better visual field test to be invented.