April 24, 2024

Orthokeratology: Vision Improvement through Overnight Therapy

Orthokeratology, also known as ortho-k, is a revolutionary contact lens-based technique used for temporary improvement or reduction of myopia. This technique uses specially designed rigid gas permeable contact lenses worn overnight to gently reshape the cornea and temporarily reduce near-sightedness during waking hours. The lenses are then removed each morning allowing clear unaided vision during the day. As the corneas natural shape returns each night this non-surgical procedure can be repeated long term.

How does Ortho-K work?
Ortho-K lenses are designed to apply gentle pressure on the central cornea while worn overnight. This compression molds the corneal shape and temporarily reduces myopia or near-sightedness during waking hours. While wearing the lenses, the central cornea becomes slightly flattened which increases the optical power of the eye. This compensates for near-sightedness by bringing the retina into better focus without glasses or contact lenses during the day’s activities. Once the lenses are removed in the morning, the cornea gradually returns towards its original shape but retains some of the temporary refractive effect, allowing clear distance vision for hours without optical aids.

Benefits of Orthokeratology
Ortho-K offers an effective alternative to glasses or conventional contact lenses for the temporary reduction and management of low to moderate levels of myopia. Some of the key benefits include:

– Freedom from spectacles or contact lenses during waking hours. This improves comfort, safety for sports and other activities.

– Possible slowing of myopia progression in children. Some clinical studies show reduced rates of myopia progression with overnight orthokeratology compared to spectacle lens wear.

– Reversible, temporary effect each day allows eyes to breathe at night without contact lenses. This may reduce risk of contact lens related complications.

– Discreet alternative to glasses for school, work or social occasions. No lenses are visible in the eyes during daytime hours.

– Preserves peripheral vision better than glasses. No lenses in front of the eyes impedes side vision.

– Potential reduction in higher order aberrations which may help reduce risks of developing other ocular conditions like cataracts.

– Long-term cost savings versus annual eye glasses or daily disposable contact lenses. Ortho-K lenses can usually last 1-2 years.

Patient Selection and Lens Fitting
Ortho-K treatment is generally most suitable and effective for patients between 9-40 years of age with up to -6.00 diopters of myopia and up to 1 diopter of astigmatism. Careful patient selection and proper lens fitting by an experienced orthokeratology specialist is essential for success and safety. The fitting process involves:

– Comprehensive eye exam and eligibility assessment.

– Pre-treatment corneal mapping using a placido disc or topography to analyze existing corneal shape.

– Specialist design of ortho-k lenses based on pre-treatment topography results.

– Initial lens placement and instruction in insertion/removal technique by the eye care professional.

– Follow-up monitoring visits in early weeks to ensure proper lens settling, comfort and visual outcomes.

– Repeat mapping and lens adjustments as needed until desired refractive outcome is achieved.

Precautions and Risks
While orthokeratology treatment is generally safe when performed by a trained eye care professional, there are certain precautions and risks to be aware of:

– Risk of infection if lenses are not handled, cleaned and stored properly. This risk is low compared to daily wear contact lenses.

– Potential for corneal inflammation, abrasions or scarce if lenses are not inserted or removed carefully.

– Temporary visibility and blurry vision issues may occur as corneas adjust initially. Usually resolves within a few weeks.

– Rate of myopia control varies between patients. May halt progression but not fully stop myopia development in all children.

– Not suitable or recommended for high levels of myopia over -6.00 diopters or astigmatism over 1 diopter. Vision reducing affects may occur.

– Temporary effect requires nightly lens wear. If discontinued, refractive effects diminish over time as cornea returns to original shape.

– Rare complications like corneal ulcers or scarring are possible if not properly fitted and cared for under specialist supervision.

In summary, orthokeratology is an effective non-surgical option for temporary myopia reduction when performed carefully by an experienced orthokeratology practitioner. Understanding risks and following all care instructions carefully helps ensure a safe and satisfactory outcome. Regular check-ups are advised especially for growing children. With proper care and management, ortho-k can provide clear daytime vision without regular optical aids.

1. Source: Coherent Market Insights, Public sources, Desk research
2. We have leveraged AI tools to mine information and compile it