How to Get Started With Orthokeratology
BY EDWARD S. BENNETT, OD, MSED
Whether you agree with it or not, interest in orthokeratology is skyrocketing. Developments like consumer interest in myopia control (via refractive surgery), multizone design lenses, corneal topography instrumentation and overnight wear complement the use of these lenses in young progressive myopes to stabilize myopic progression.
A practitioner can fit orthokeratology lenses as long as he designs his own and does not make unsupported claims about his results with this procedure. John Rinehart, OD, developed a good summary of ortho-k guidelines for practitioners (Table 1).
Multizone Lens Designs
Multizone lens designs accelerate the effect of ortho-k, often with only one pair of lenses. High-quality multizone lens designs include G. P. Specialists' Fargo lens, Paragon's CRT, Correctech lenses, Contex's OK lenses, Euclid Systems Corporation's Emerald lens and others. Several companies including Paragon, Euclid and Correctech are pursuing overnight ortho-k FDA approval.
TABLE 1: Guidelines for Advertising and Promoting Ortho-k (Rinehart)
1. According to the Food and Drug Administration (1998): "A licensed practitioner may individually design and prescribe an RGP orthokeratology lens for a particular patient within the scope of his/her practice. However, eyecare practitioners who promote orthokeratology in their practice should avoid making exaggerated and unsupported claims of safety or effectiveness."
2. The practitioner who is advertising orthokeratology is responsible for all statements, regardless of who creates the advertisement. All information must be accurate and must not deceive the patient.
3. Competent and reliable scientific evidence must support claims of safety and efficacy.
4. Avoid claims of permanence and make prominent mention of the need for retainer lens wear.
To succeed with the different designs, perform a careful diagnostic fitting. Learn the dynamics behind each zone to troubleshoot fitting problems. These designs have a larger than average overall diameter (often 10.0mm), a small optical zone diameter (often 6.0mm), and are intended to center well and move very little with the blink.
I recommend any seminars by Drs. John Mountford, Harue Marsden or John Rinehart. Drs. Roger Tabb and Don Higgins offer comprehensive continuing education courses. Paragon CRT certification seminars, required for participation in Paragon's Corneal Refractive Therapy program, teach dynamics behind fitting and troubleshooting multizone lenses.
Upcoming educational resources include a comprehensive ortho-k website.Written and online resources include a chapter by Dr. Marsden with accompanying video segments in Manual of Contact Lens Prescribing and Fitting with CD-ROM. Dr. Rinehart contributed a helpful chapter in an upcoming text Rigid Gas Permeable Contact Lenses (Bennett, Hom, Grohe). Both are available from Butterworth-Heinemann. Dr. Mountford is authoring a comprehensive ortho-k text. You can subscribe to a new ortho-k newsletter at http://www.ortho-k.net/profess.htm. Also check out the British Orthokeratology Society (http://www.boks.org.uk/).
During the February, 2001 SECO meeting, a steering committee formed to improve educational and scientific advancement of orthokeratology.
Acknowledgements: Joe Barr, OD, MS, FAAO, Milton Hom, OD, FAAO, Marjorie Rah, OD, PhD, John Rinehart, OD, and Roger Tabb, OD, FIOS.
Dr. Bennett is an associate professor of optometry at the University of Missouri-St. Louis and executive director of the RGP Lens Institute.