EyeTools Optometry Skills

396: Very small letters on a visual acuity chart

I have a visual acuity chart with a last line of 6/4 letters. Most of my patients can’t see letters this small even if they can see the 6/6 letters. Some patients tell me that they could read the last line of letters on the chart at their previous opticians and wonder why they can’t read the last line on my chart. What can I do about this?

 I worked in a practice that had a visual acuity chart with a 6/4 line of letters. I too notice that patients commented that they couldn’t read it when they could read the bottom line of letters at their previous eye care specialist. It’s very likely that the last line at their previous practitioner consisted of 6/5 or even 6/6 letters. I don’t like to have worried patients so I covered up the 6/4 letters on my chart. These letters are too small for most people, even those with good eyesight to see and just cause them to worry. A line of letters with 6/4 is not clinically necessary or useful.

I also sometimes examine people in their own homes using a tablet device at 3 metres. This has six lines of letters ranging from 6/12 to 6/4. Most people can only read the first three lines and struggle with anything smaller than 6/8. Some are worried about why they can’t read the last three lines. As many of my home-visit patients are over 80 years old and have some cataracts and age-related macular degeneration. It’s not appropriate to cover over the last three lines on the tablet so if a person exhibits concern at being able to read these letters I tell them that they have done well to read the first three lines of letters and that it’s normal for the age group they are in.

 We have to be careful that the way our visual acuity charts are configured does not cause unnecessary worry for our patients.


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