Glare Sensitivity Tests – Vision Testing

The first signs of a cataract are usually found when the eye doctor performs a routine exam and tells you that your glare sensitivity is off. The only problem is most people don’t know what glare sensitivity is or even how is it measured.

Most cataract exams are measured just as general eye exams are done, but there are a couple of additional tests involved (e.g., glare sensitivity, contrast sensitivity). In people that have cataracts or the beginnings of cataracts, their glare sensitivity seems to be more pronounced. Sometimes so much so that it interferes with their night time driving. This is where the light the headlamps produce starts to blend together or the person starts to see colored rings caused by the glare.

When people start to get this blurred night vision, or the daylight glare seems more intense, then it may be time to go to the eye doctor. The doctor will perform a test which will measure your eyes’ refraction. This test is called a retinoscopy, and he can see the errors without any help from you. Then he may do a phoropter exam and a visual field test. Other tests an eye doctor will do will include a Tonometry test, which measures the intraocular pressure of the eye. The doctor will then study the retina by doing an opthalmoscopy. This is important because the retina transmits the light signals from the eye lens to the brain.

Once that has been done, you will be given a test for reading vision and distance vision. When the doctor believes you might have a cataract, these tests will be done in both high and low lighting.

Now there is a special test that is given to patients called the glare test. Patients with cataracts often say that their vision is impaired by glare; even when there isn’t a glare they often see a glare. The doctor administers the glare test with a device that measures that glare. This allows the doctor to see how much glare the patient sees. This test also becomes the guide as to whether the cataract problem is worsening, stabilizing, or remains the same.