1, pseudomyopia: children and adolescents due to strong regulation, after excessive eye use, can cause a decline in distance visual acuity, before the pupil dilatation diopter performance for myopic refraction, when the use of ciliary muscle numbing agent pupil dilatation, the regulation relaxed, at this time the distance visual acuity back to normal, the examination of the shadow diopter performance for positive or mild hyperopic refraction, this myopia is called pseudomyopia, do not need to wear glasses for correction. 2, true myopia: the use of ciliary muscle paralyzing agent dilated pupil examination performance of myopic refraction, dilated pupil before and after the change in distance visual acuity is not significant, can be combined with the eye axis growth.