Optometric Management Tip # 78 - Wednesday, July 16, 2003
Computerized Acuity Charts
I like to stop and think how everything looks to the patient during the exam procedure, since doctors don't usually experience that side of the process. The visual acuity chart is a vital part of the eye exam experience. Let's face it; it IS what the patient is looking at the entire time they are in our exam rooms! In my opinion, it is time for progressive optometric practices to move beyond projected charts. Projection systems often suffer from insufficient brightness, uneven illumination, dust particles in the lens system, and non-symmetrical trapezoidal-shaped backgrounds due to angles of projection.
As experts in vision, contrast and lighting, our offices should use an eye chart medium that is an example of perfect clarity. We also should care about the impression we make with this basic instrument of our craft - and in many cases, the old manual project-o-chart is the same thing that was used for refraction in the 1940s! Remote controlled projectors give a better image, but I think a computer monitor and a keyboard on the desk to control it is the best image of all.
I've been using a digital acuity system in all our exam rooms for the past 5 years and its great! I like the systems that can run on older PCs that I was going to retire anyway. These acuity programs do not require much computer power. I use a dedicated computer for the chart and a second networked PC in the exam rooms for patient records, retinal photos, topography and visual fields.
I also opted to use our older standard 15-inch monitors as the displays, since we have refraction mirrors in the exam rooms and the monitor is mounted behind and above the patient, and they view it in the mirror anyway. Space is not an issue and the monitor looks quite impressive and immediately looks like a computer screen. I love LCD flat screens, and we use them in our other computer locations throughout the office, but I like to be economical when possible.
I mounted the acuity monitors to the wall on swivel platforms made for monitors and television sets. I drilled a large hole in the drywall behind the monitor so the power cord and PC video cable could be hidden in the wall because I don't like to see the clutter of cords. I just pulled the cords out at the bottom of the wall and ran them to the PC in the corner of the room. I use wired keyboards for the acuity PC, and I don't need a mouse to control it. I just tap the arrow keys, a number key or a function key to change the chart. You may need extension cables for the PC video cable and the keyboard cable - I use them with no problem. Wireless keyboards work well too. I like digital acuity systems that let you use your own computer hardware and replace it when needed, rather than integrated systems that tend to be more expensive.
Here are a few more advantages:
Now - the question may be, where do you find these devices? As you may know, I'm very careful to never give any plugs in this newsletter for specific brands of eye care products. I think it is best for me to remain generic because I don't want to have my message construed as a sales pitch for any company. I'll always disclose if I have any financial interest in a product (I do not in this case). All I can say is computerized eye chart programs are out there. Ask your colleagues, ask equipment dealers (although many do not sell them, so they may not be that helpful), seek out vendors at convention exhibit halls, or do a Google search.
- You can change the optotypes at will to avoid the patient memorization factor on any given acuity line.
- You can display all the special charts you wish - red/green, pediatric symbols, single line or letter, Worth 4 dot, astigmatic clock dial, etc.
- Calibration of letter size is automatic, just enter the room length.
- You can even refract with the lights on - a more natural environment and easier on presbyopic doctors!
Best wishes for continued success,
Neil B. Gailmard, OD, MBA, FAAO
Chief Optometric Editor, Optometric Management