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Light streaks?

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Q:  When I am driving at night I often notice the oncoming headlights, and sometimes streetlights, have streaks of light coming out of them. I just realized many other people do not see this.  Why?

A:  Many people have the same experience as you describe, but mistakenly assume this is “normal".  It is not. There are certainly other eye diseases that can cause this, but, the two most common causes of seeing light streaks or “smeary” lights depend on age.  For those over 50 years of age, the frequent cause would be early-stage cataracts. While generally not needing surgery, this early symptom often causes a change in vision correction as well. Your eye doctor can easily diagnose this with our in-office biomicroscope.

For younger people, the common cause would be uncorrected astigmatism.  To make this clear, let’s first understand what astigmatism really is. Vision problems like near and far-sightedness are usually caused by the overall length of your eyes. Longer eyes (front to back) tend to be nearsighted, or myopic, while shorter eyes tend to be farsighted, or hyperopic. Astigmatism depends upon the shape of the front of our eyes.

The clear layer called the cornea on the front of our eyes is commonly not truly round in shape.  It is often shaped like the back of a spoon...having different curvatures in different directions.  This bends or blurs the light entering our eyes, making our vision less than sharp.  It so happens that the type of blur we see with astigmatism makes images or lights appear “smeared” out in some direction...up and down, left and right, or even at an angle! This smearing effect can make headlights or any light bulb appear to have streaks or glare stretching out from the light source.

The best news is that this can be solved fairly easily in most cases. Astigmatism is fully correctable with glasses, and usually with contact lenses as well! The bottom line:  schedule your eye exam to see what is causing this, and have it corrected to enjoy normal crisp vision again.