Appropriate Scleral Lens Sagittal Depth | 合法醫療器材資訊網

Scleral contact lenses rest on the sclera, vaulting over the entire cornea and limbus to avoid irritating or scarring those tissues. The amount of space between the lens and the cornea is typically referred to as sag. Sagittal depth actually refers to the entire contact lens from the center of the lens to the plane that the edges circumscribe. Various brands of scleral contact lenses allow you to manipulate the sag in different ways in order to achieve the desired vault over the cornea. Some brands allow you to actually specify the sagittal depth where others require you to manipulate the base curve. A steeper base curve typically results in increased sagittal depth where a flatter base curve reduces it. Regardless of how you achieve clearance over the corneal surface, there is an ideal amount of space between cornea an...