ABSTRACT
A contact lens is slightly flatter than the cornea. It produces a contact lens draw when the meniscus from the contact lens solution pulls the edge of the lens inward. The reactionary force pulls outwards against the cornea. The cornea acts like a rigid contact lens and draws outwards on the sclera. The eyeball tends to become less elongated and thicker around the middle to reduce the strangle hold of the oblique muscles around that part of the eye. When the brain interprets the eye to be in distant focus mode (instead of near focus mode when the oblique muscles were tense), the “focal point draw” then flattens the crystalline lens and eyeball once the motor cortex sends the proper message to the ciliary and rectus muscles.
The power of the prescription determines the flatness of the contact lens, and its flatness determines its “draw.” A “contact lens draw” “loosens” the tension of the oblique muscles to allow a “focal point draw.” The flatness must be correct before it neutralizes the mild or moderate myopia. Ortho C attends to the following relationship: there is a correlation between the prescription expressed in diopters and the lens’ equivalent flatness—also expressed in diopters. The calculation for the flatness factor is given in the chapter The Procedure.
If your prescription is −1.25 D for both eyes, then the flatness factor is 1.25 D. You would expect the cornea to flatten out or become less steep by 1.25 D, but it does not. The curvature remains the same to allow a constant draw of 1.25 D to “loosen” the oblique muscles when the “draw” from the lens is transmitted to the cornea. The cornea becomes an extension of the contact lens and “draws” against the eye to make it wider from top to bottom and side to side. Theoretically, the oblique muscles’ tightness decreases by 1.25 D.
94The ortho C lens does not actually reverse your nearsightedness. It is the motor cortex responding to the correct neurosensory message: a blur image in the distance and a more relaxed set of oblique muscles when you look at something far away. The brain initiates the proper neuromotor message to the ciliary muscle and rectus muscles when it interprets the decrease in tension as an eye that is in distant focus mode.
