If you are having an issue with your vision, you may be suffering from a refractive error. To better determine if your eyes are affected by refractive errors, your optometrist will complete a comprehensive eye examination, which will include a retinoscopy.

What is a retinoscopy?

Retinoscopy is an examination of the retina that provides an objective measurement of refractive error. The procedure is performed by an optometrist during an eye exam to determine if a patient has emmetropia, myopia (nearsightedness), hyperopia (farsightedness) or astigmatism.

Reasons for retinoscopy

Retinoscopy is typically performed during a routine eye exam to determine if the eyes have any errors of refraction and if corrective lenses are needed to achieve clear vision. Since this is an objective procedure and does not require a response from the patient, it is often used to diagnose vision problems in children and those who are unable to communicate effectively.

In some cases, a retinoscopy may be the only examination needed, particularly if a patient has emmetropia and can see clearer without glasses or contact lenses. However, if refractive errors are detected, retinoscopy is usually followed by other subjective tests to determine the exact corrective lens prescription needed to achieve clear vision.

How retinoscopy is performed

An optometrist performs retinoscopy using a tool called a retinoscope. The retinoscope consists of a light, a condensing lens that concentrates the light and a mirror. During the procedure, the optometrist uses the retinoscope to shine light through your pupil, then moves the light vertically and horizontally across your eye and observes how the light reflects off the retina.

The way the light reflects will determine if you can see clearly or if you are nearsighted, farsighted, or have astigmatism. In some cases, your eyes may be dilated before a retinoscopy is performed. When your eyes are dilated their focusing ability is temporarily limited and the pupils are large, which makes it easier to see how the light reflects and can lead to a more accurate diagnosis.

If you are due for an eye exam or have noticed that your eyesight is changing, schedule an appointment with your optometrist. The American Optometric Association recommends that both children and adults have their eyes checked at least once every two years. However, for those who are at risk for vision problems or whose vision is changing, annual eye examinations are recommended.