keratology

Keratology, also known as orthokeratology, is a non-surgical refractive correction approach that uses specially designed rigid gas-permeable contact lenses worn overnight to temporarily reshape the cornea. The primary aim is to reduce daytime dependence on glasses or contact lenses, usually for myopia, with possible mild hyperopia or astigmatism as secondary targets.

The mechanism involves overnight wear of reverse-geometry lenses that gently flatten the central cornea by redistributing the epithelial cells. After lens removal in the morning, the cornea retains a new shape for part of the day, improving distance vision without lenses. The duration and stability of the effect depend on the lens design, wearing time, and individual corneal biology.

Indications and suitability include reducing reliance on daytime corrective lenses, and in children, slowing the progression of myopia. Adults with low to moderate myopia or certain mild astigmatic errors may also be candidates. Keratology is not appropriate for high refractive errors, active eye disease, or certain corneal conditions, and it is not a permanent cure.

Safety and efficacy considerations are important. Some studies indicate potential slowing of myopic progression in children, while results vary. Risks include infection, corneal ulcers, corneal warpage, ulcers, and epithelial compromise if hygiene and lens care are inadequate. Regular eye exams, proper lens hygiene, and prompt reporting of symptoms are essential.

Procedure and management typically involve a professional fitting for overnight lenses, initial follow-up visits, and ongoing maintenance. Lenses are worn overnight for several hours, then removed during the day. Ongoing monitoring ensures corneal health and assessment of vision stability, with lens replacement as recommended by the clinician.