dynamic retinoscopy
Dynamic retinoscopy is retinoscopy performed while the patient fixates a near target, and it gives an objective measure of the accommodative response.1 With motion indicates a lag of accommodation, against motion indicates a lead, and neutrality means the accommodative stimulus and response are equal.2
In the monocular estimate method (MEM), the patient reads a card mounted on the retinoscope at the working distance with both eyes open.1,3 The examiner estimates the lens power that would neutralize the reflex, then confirms it by holding that lens before one eye for less than a second, because a longer exposure changes the accommodative response.1,2
The accommodative lag on MEM is usually about +0.50 D, and most non-presbyopic patients show lags of 0 to 0.75 D.2,3 A lag greater than +1.00 D may represent accommodative insufficiency, and a reflex that needs a minus lens to neutralize suggests accommodative spasm.3 The result helps diagnose binocular anomalies and predict the response to some forms of therapy.1
More detail
Expected MEM findings are +0.25 to +0.50 D, and school-aged children show a mean lag of 0.34 D.1,2 Low neutral dynamic retinoscopy adds plus lenses in 0.25 D steps to the distance correction until the reflex is neutral at 40 cm.2 A result of +0.75 D means the stimulus and response are equal at 1.75 D, which is 0.75 D less than the 2.50 D demand of the test distance.2
Bell retinoscopy measures the lag as a distance, moving a reflective sphere toward the patient until the reflex changes from with to against motion.1 Nott retinoscopy keeps the target fixed and moves the retinoscope to and fro to find reversal, and it typically shows a slightly lower lag.3
Sources (7)
- Clinical Procedures for Ocular Examination, ch. 4
- Practical Binocular Vision Assessment, ch. 5
- Pickwell's Binocular Vision Anomalies, ch. 2
- Rutstein, R., Daum, K. (1997). Anomalies of Binocular Vision: Diagnosis & Management, Mosby.
- Rouse, M. W., Hutter, R. F., & Shurtleff, D. B. (1984). A normative study of the accommodative lag in elementary school children. American journal of optometry and physiological optics, 61(11), 693-697.
- Leat, S. J., & Gargon, J. L. (1996). Accommodative facility in prepresbyopic adults. Investigative ophthalmology & visual science, 37(5), 926-933.
- Scheiman, M., Gallaway, M., Coulter, R., Reinstein, F., Ciner, E., Herzberg, C., & Parisi, M. (1996). Prevalence of vision and ocular disease conditions in a clinical pediatric population. Journal of the American Optometric Association, 67(4), 193-202.
Reviewed October 2026
Related terms
Nearby in the glossary
- doll’s-head maneuver
- Duane’s syndrome
- ductions
- dynamic retinoscopy