Retinoscopy is a technique I use to both objectively determine the Refractive Error of the eye (Farsighted, Nearsighted, Astigmatism) as well as assess how the eyes focus & work together. By itself this test can determine the possible need for glasses & it quick, easy, accurate and requires only minimal cooperation. A patient only needs to look at a target either hand held or in the distance for a time period that only takes a few seconds. Most children, including infants, can look at targets long enough to allow successful Retinoscopy in the office.
Over the years, the Retinoscope has proven to be an excellent first start in my exam & is a highly effective way of reducing time spent on an exam without compromising the quality of the result. For patients who are young, patients who have a difficult time communicating, or those with special needs, Retinoscopy has become my primary method of obtaining a baseline glasses prescription.
Are Dilating Eye Drops Necessary for Retinoscopy?
The reflux is easier to see when the pupil is large & most children are naturally gifted with large pupils. Based on the needs of the child I will often not dilate if I find a stable and consistent reflex. This allies for a tears-free experience and is a preferred method of mine. Having performed Retinoscopy on over 25,000 patients I feel very confident in my ability to determine when & if dilation is necessary. Children’s eyes are typically dilated for Retinoscopy when an unstable reflex is noted & compliance with fixation is lacking. Because the drops temporarily limit the eye’s ability to accommodate or focus this may allow for a more accurate determination of the distance refractive error, but also put the eyes in an unnatural state of focus and gives less information on how the eyes actually function.
Different Types of Retinoscopes: Spot vs Streak
Both types of Retinoscopes are used to determine a prescription objectively, but each has advantages based on the needs of each individual patient. Because Astigmatic eyes create a special linear fundus reflex, a narrow rectangular beam of light (or streak) is most useful in refining this condition, thus the greatest use for streak Retinoscopy is slightly older, better focused patients who need to have the exact Astigmatism correction refined.
The Spot Retinoscope is the tool of choice for Developmental Optometrists. Developmental Optometrists believe that vision can be developed and improved through a learned process, and that it is never too late to improve! Because of its dynamic nature it reveals subtle changes in how the eyes function and work together, and it is also much faster. Simply put, the Spot Reinoscope offers more information and is most useful with young children or when developmental concerns are present.