Keep the lights on
In some optical retail shops, the standard is to turn off the room lights during eye refraction tests. This is good for objective exams like retinoscopy or slitlamp biomicroscopy. But for subjective exams (i.e. the comparison between lens 1 and 2), this is not optimal.
This induces a greater error of refraction, resulting in a poorer visual acuity (score). Which means that you’ll need a greater power for correction (over-refraction).
This often leads to two situations:
- Patient gets dizzy, the doctor tells the patient that she’ll be comfortable with the new lenses in due time.
- The doctor notices that the patient is uncomfortable during trial, he modifies it to a lower grade. And again. And again.
Either situation can be frustrating for both the doctor and the patient.
I have to admit, I used to follow the exact standard of procedure. Although there are some studies that suggest that there is no significant difference in room illuminations, my feedback here was the stack of paperwork I had to make to explain why my patients would come back in less than a month because they couldn’t use their prescriptions for long periods of time.
I didn’t think that there was much of a difference in my procedures than with my colleagues. Until I saw their stack of paperwork as well. Some even came back within a week!
Since then I started keeping the lights off, as an experiment. My paperwork lessened.
I emphasized on patient education. If at first instance they’re not able to tolerate the best correction, the best lenses are modified to a lower set of lenses. The modified version is slightly blurry, but comfortable to use—especially when it’s for prolonged use. I then suggest a follow up appointment to see if they’re able to tolerate a higher prescription.
The only exception to keep the lights off is when the patient works in dim lights most of her waking hours, or the prescription is only applicable in dim environments.
Keep the lights on during eye refraction, by default.
Note: This here is a professional opinion. I do not know your case so please consult a licensed professional regarding your vision.