At Spectrum Eyecare in Peachtree City, we receive many questions about night vision.
A common theme relates to complaints of poor night vision (even with glasses on). Other patients report that they have been told that they do not need glasses, but they feel they have poor vision at night and/or when it is raining. While there can be a number of causes of this feeling, there are typically 5 causes of this complaint.
1) Cataract formation
Cataracts are a normal part of the aging process that result in a gradual clouding of one of the lenses in the eye. This clouding reduces the amount of light that can enter the eye. The clouding also dramatically increases glare. This is especially problematic when driving at night or in rainy conditions. When the cataract is starting to impact quality of life, then cataract surgery is indicated. In most cases, this is a 15 minute out-patient surgery with no stitches.
2) Dry Eyes
Most people mistakenly believe that the main focusing lens of the eye is the cornea, but that is not the case. The cornea exists to create a lens made out of your tear film. If you have dry eye, then you will have a poor quality tear film. That will cause reduced quality of vision, especially at night. There are many treatments for dry eye. See our dry eye page for more information
3) Scratched or pitted eyeglass lenses
As your glasses age, they begin to develop fine scratches and pits in the lenses that will effect the optical quality of the lens. This, in turn, will blur the vision, and cause glare issues, especially from oncoming headlights. Replacing the lenses can solve this problem, especially if the new lenses incorporate an anti-reflective coating.
4) Retinitis Pigmentosa (RP)
This relatively rare disease destroys the part of the eye that senses vision at night, resulting in serious night blindness. Unfortunately there is no treatment other than low vision aids for patients with RP.
5) Higher order aberrations (HOA)
This final category is one that most people have not heard of. Generally speaking, the typical components of a prescription, such as nearsightedness and astigmatism only account for about 90% of your total correction. The other factors, such as chromatic and spherical aberration (among others) primarily effect the vision at night. Eye doctors lump together all those other components in a category that we call “Higher order aberration” or “HOA’s.
In some patients, HOA represent their only vision problem. These patients often complain about blurred vision, only to be told by their eye doctor that they do not need glasses.
New technology from the German optics company Zeiss has allowed us at Spectrum Eyecare to measure these HOA’s. Moreover, they have new lenses that allow for incorporation of HOA’s to allow for the best possible night vision. At Spectrum Eyecare, we are one of only three practices in Georgia that have implanted this technology in our practice. We measure each patient to see if they need this special lens technology incorporated into their prescription.
Whatever the cause of your night vision problem, at Spectrum Eyecare, Dr. Henahan will take the time to fully evaluate your eyes to discover what is causing your difficulty. He will also take the time fully explain the issue and your options for solving the problem.
Dr. John Henahan is a Peachtree City resident and founder of Spectrum Eyecare.