Physiological Considerations in the Design of Internal and External Surfaces of Fluidless Scleral Contact Lenses

As the understanding of corneal and ocular physiology increases, the factors of negative pressure on the cornea, and the muscle pump effect the eyelids impose upon the fluid contents of the globe, must be considered in the design of scleral lenses. By the use of relief channels in internal and external surfaces and perpendicular, as well as horizontal, perforations, there is little impingement of minimal pressure circulation, and suction or negative pressure is eliminated.