REFRACTION--What is it.....and Do I need one?
On the day that you present for your eye examination, especially if it is your "annual examination" you will likely be asked if you want a "refraction".
That can be a puzzling question and can even cause some patients to panic. It might not even be a fair question because you are most accustomed to your doctor expressing his recommendations; rather than him relying on you to order your own tests or examinations. After reading this brief summary, there will be no reason for you to feel confused or stressed the next time this question is asked.
A refraction is the test that is the starting point for your doctor to eventually determine if your symptoms; especially those regarding clarity of near and distance vision are simply due to a need for glasses or if they are the result of another condition or eye disease. If you have had previous eye examinations you might recall that your eye doctor (or his qualified technician) either places a set of trial frames (basically glasses without lenses) on your face and slips in and out a variety of lenses, asking which one makes it "better or sharper". Or, More commonly, you sit at a device suspended by an arm that is swung in front of your face, and similar to trial frames, a variety of lens choices are presented for you to specify which is best. As the process is nearing completion, you are asked to read as far down as you can on the eye chart. Each eye is tested separately and a final "refraction" is obtained, which usually forms the basis for your new glasses prescription.
Sometimes, you may go through the entire refraction process and you might not get a glasses prescription. Now you are asking yourself, how could that be? There are many answers to that question; but here is the most important one regarding the health of your eyes:
It is possible that no glasses, or no change from the prescription in your present glasses, will further improve your vision. Do not mistakenly conclude that you went through this refraction process for nothing. Remember that we said this is a starting point. Based on the information that your eye doctor obtained from the refraction, he now should conclude that if your spectacle corrected vision is less than perfect that it is likely the result of an eye disease that needs immediate further investigation and possible future treatment. A classic example of this might be the presence and advancement of cataracts. Sometimes a refraction will reveal that the blurry vision caused by cataracts can be (totally or partially) remedied by the right new glasses prescription. Alternatively the refraction might reveal that because a spectacle change will not improve the vision, that cataract surgery is indicated for you to restore better vision.
To summarize, if you have unexplained new onset of blurry vision, or a change in your vision, or vision that is inadequate for tasks that are important to you (either for near or far)--then you need a refraction when you visit your eye doctor. If your vision is excellent, your present glasses are in good condition, you have no visual complaints, and you demonstrate that you can see the eye chart across the room and also easily see up close reading material, then it's likely you don't need a refraction. Knowing this, you should feel free to tell your eye doctor or his staff whether or not a refraction is worthwhile for you.
Blog posted by Dr. Martin Shapiro, a board certified ophthalmologist performing comprehensive eye care for over 30 years. For more information or to schedule an appointment please contact us at 203-878-1236 or at any of our 5 offices in Milford, Orange, Branford, Shelton, or Wesport. We’re looking forward to hearing from you soon.