by Liz Trauernicht, Director
MD Foundation
A significant amount of evidence finds that very bright light, especially blue light, can damage the macula. Traditional slit lamp devices used during eye exams produce high light levels, which may be problematic for people with macular degeneration.
Before these devices can be used effectively, the pupil of the eye must be dilated (the mydriatic process), then the retina is subjected to the strong light for at least 20 seconds at a time. On the other hand, non-mydriatic retinal cameras, such as those made by Optos, Canon, and Nidek, do not require the pupil to be dilated, and they use low light levels to produce highly sensitive digital photographs and videos (Ophthalmology. 2001; 108:572–585). These cameras make it possible to photograph very fine and subtle changes not visible with a standard high-intensity slit lamp. For anyone needing multiple eye exams, non-mydriatic cameras would seem to be safer for the retina than slit lamps.
Other benefits of using a non-mydriatic camera for eye exams are:
- less time spent in the clinic
- no need for wearing dark, vision-hindering lenses afterward
- no need for additional assistance, such as a driver, immediately after leaving the clinic
Fundus photos that flash bright lights into the eyes are still necessary for a thorough retinal exam, but the risk of unnecessary light exposure from slit lamps can still be avoided. MD Foundation recommends that, before scheduling an appointment, patients ask their eye care doctors if non-mydriatic retinal cameras are an option.