MEM Dynamic Retinoscopy is an objective method to measure the accommodation reaction.

Steps:
(1)Correct the refractive error of both eyes completely and adjust the pupil distance.
(2)The distance between the ophthalmoscope and the tested eye is 40cm. The examination room maintains normal lighting. The near vision card is attached next to the peephole of the ophthalmoscope. Select the corresponding line of vision chart,which is above the row of chart with best vision on near vision card. Measure the right eye first, and then the left eye.
(3)Ask the tested eye to look at the near vision card through the correction lens, observe the reflected light shadow of the tested eye's retina with a vertical projection light band, and neutralize the shadow with retinoscopy rack set.

(4)When the retinal reflection light of the tested eye moves smoothly, add the convex(+) sphere lens until the reflected light is neutralized.Record the added convex(+) sphere lens value, which is the accommodation lag;
When the retinal reflection light of the tested eye moves smoothly, add the concave(-) sphere lens until the reflected light is neutralized. Record the added concave(-) sphere lens value, which is the accommodation lead.
(5)Because the dynamic refractive state is not stable enough, the examiner must quickly judge the nature of retinal reflected light and shadow, and quickly increase or decrease the sphere lens with the help of retinoscopy rack set to determine the accommodation reaction.
(6)Record the results, for example:
OD: + 0.75D   right eye accommodation lag 0.75D
OS: - 0.50D    left eye accommodation lead 0.50D