Refraction Assessment


Lt Col Reynolds
The term “refraction” describes the manner in which waves of light are bent as they pass through the cornea and lens of the eye. The refraction assessment test helps providers determine the prescription of corrective lenses. This test is used only for patients who require glasses or contact lenses. Dr. Patel, what else can you tell us about refraction assessment?

Dr. Patel
Well, Dr. Reynolds, the provider may use an automated refractor to measure the eyes and determine the prescription needed to correct the refractive error. Another technique used to evaluate refractive errors is called retinoscopy. In this procedure, the provider shines a light into the eye and measures the refractive error by evaluating the movement of the light that is reflected by the retina.

In many cases, the provider will continue the refraction assessment by asking the patient to look through a device called a phoroptor. This is a mask-like device that contains many different lenses mounted on a wheel. The provider will try a variety of lenses to fine-tune the prescription, determining which lens offers the sharpest vision.

By repeating this step several times, the provider is able to find the lenses that give the patient the greatest possible acuity.