Dr. Sasmita Das

The cornea is a clear, dome-shaped surface that covers the front of the eye, acting like a window that allows light to enter and focus onto the retina to form the images we see. Though it measures only about half a millimeter thick, it is remarkably strong and intricately organized. Structurally, the cornea is made up of five distinct layers, each with a specialized role. The epithelium forms the protective outer barrier against dust, bacteria, and moisture. Beneath it lies Bowman’s layer, a tough, transparent sheet that adds structural strength. The stroma, which makes up most of the corneal thickness, is composed of orderly collagen fibers that provide both clarity and flexibility. Descemet’s membrane serves as a thin but resilient shield against infection and injury, while the innermost endothelium maintains corneal transparency by pumping out excess fluid.

Functionally, the cornea provides about two-thirds of the eye’s total focusing power. By refracting incoming light and directing it through the pupil and lens toward the retina, it plays a central role in producing clear vision. Because of this, any irregularity or damage can have a significant impact on sight. Common corneal disorders include keratoconus, a progressive thinning and bulging of the cornea; corneal ulcers, which are open sores typically caused by infection or trauma; Fuchs’ dystrophy, a condition marked by deterioration of endothelial cells; and corneal abrasions, painful scratches that usually heal quickly with care.

Modern ophthalmology provides a wide range of treatment options—from corneal cross-linking and laser-assisted procedures to full corneal transplantation for more advanced conditions. Emerging technologies such as artificial corneas and stem-cell-based therapies are also showing promise for future vision restoration. Ultimately, the cornea may seem simple, but it plays an essential role in the visual system. Protecting its health through good eye care habits, regular checkups, and timely treatment of infections is key to preserving lifelong clear vision.