Retinoscopie

Retinoscopy is a clinical technique used to estimate an eye’s refractive error by observing the movement of light reflected from the retina when illuminated with a retinoscope. It is widely employed by optometrists and ophthalmologists, particularly in children or nonverbal patients, to obtain an objective sense of refractive status and to screen for astigmatism.

During the examination, the patient typically fixes a distant target in a dim room. The clinician holds the retinoscope at a fixed working distance from the eye and projects a streak or spot of light onto the pupil. By moving the instrument and watching the retinal reflex, the clinician infers whether the eye would focus light in front of or behind the retina. If the reflex moves in the same direction as the retinoscope, this is called “with” movement; if it moves in the opposite direction, it is “against” movement. The goal is to reach a neutral reflex, at which point the lens power required to neutralize the reflex serves as an estimate of the refractive error, with adjustments for the working distance. The streak allows assessment of different meridians, aiding the evaluation of astigmatism.

Indications include screening for refractive errors in children, detecting anisometropia, and guiding prescriptions when subjective refinement is not feasible. Cycloplegia may be used in pediatric or uncooperative patients to minimize accommodation and improve accuracy. Limitations include reliance on patient cooperation, the influence of accommodation, and the need for expertise; retinoscopy is often complemented by subjective refraction and other biometric tests for a complete prescription.