What Causes a Decrease in Myopia Prescription?

Inaccurate refraction measurements, non-cycloplegic refraction, and excessive eye strain, among other factors. During refraction, if the eyes are fatigued, transient visual decline may occur; however, vision typically returns to baseline after rest. Some adults engage in prolonged near work prior to refraction, causing ciliary muscle spasm and resulting in pseudomyopia. This leads to an initially deeper (more myopic) refractive measurement. During a second refraction—after the ciliary muscle has relaxed—the measured refractive error appears shallower, giving the impression that myopia has decreased.