Keratoconus is a progressive, non-inflammatory eye disorder in which the cornea gradually thins and bulges outward into a cone-like shape. This abnormal shape disrupts the way light enters the eye, leading to distorted and blurred vision that cannot be fully corrected with standard glasses. Keratoconus typically begins in adolescence or early adulthood and can progress over several years before stabilizing.

The exact cause of keratoconus is not fully understood, but it is believed to involve a combination of genetic predisposition, biochemical abnormalities, and environmental factors. A family history of keratoconus increases risk, as do chronic eye rubbing, allergic eye disease, and connective tissue disorders. Structural weakness in the corneal collagen leads to progressive thinning and loss of corneal rigidity.

Early symptoms of keratoconus may resemble simple refractive errors and include blurred or distorted vision, frequent changes in eyeglass prescriptions, increased sensitivity to light, glare, and ghosting of images. As the condition progresses, vision becomes increasingly irregular due to high astigmatism and corneal scarring. In advanced stages, patients may experience significant visual impairment affecting daily activities such as reading, driving, and working.

Diagnosis requires a comprehensive eye examination, with corneal topography and tomography playing a central role. These imaging techniques map the curvature and thickness of the cornea, allowing early detection and monitoring of disease progression. Early diagnosis is particularly important, as modern treatments can halt progression and preserve vision.

Management depends on disease severity and progression. In early stages, vision may be corrected with glasses or soft contact lenses. As irregular astigmatism increases, rigid gas-permeable or scleral contact lenses provide better visual outcomes. Corneal collagen cross-linking (CXL) is a proven treatment that strengthens corneal fibers and halts disease progression, especially when performed early. Advanced cases with significant scarring or thinning may require corneal transplantation.

Keratoconus is a lifelong condition requiring regular follow-up. With early detection and appropriate intervention, most patients can maintain functional vision and avoid severe complications.