The following studies are provided for patients and parents for references regarding Ortho-K or CRT and myopia treatment:

LORIC (Long Term Ortho-K Research In Children) Pauline Cho showed that axial length increase was 50% in Ortho-K patients compared to the control group in glasses. Although Ortho-K slowed myopia, the effect couldn't be predicted for individuals.
Current Eye Research, 30:71;80, 2005

CLAMP (Contact Lens And Myopia Progression) Jeff Walline studied 59 RGP eyes versus 57 soft lens eyes. There was no difference in axial length growth. RGPs flattened the cornea .5D, while soft lenses steepened it .5D. RGPs slowed progression but only a small amount.

Walline JJ, Jones LA, Mutti DO, and Zanik K: A Randomized Trial of the Effect of Rigid Contact
Lenses on Myopia Progression. Arch Ophthalmol 122: 1760-1766, 2004

COMET (Correction of Myopia Evaluation Trial) Progressive Addition Lenses slowed myopic progression by .13D over five years, an effect considered negligible.

Gwiazda J, Hyman L, Hussein M, Everett D, Norton TT, Kurtz D, Leske MC, Manny R, Marsh-Tootle W, Scheiman M, and the COMET Group: A randomized clinical trial of progressive addition lenses versus single vision lenses on the progression of myopia in children. IOVS 44: 1492-1500, 2003.

CRAYON (Corneal Reshaping and Yearly Observation of Nearsightedness) An update to the LORIC study by Jeff Walline. Ortho-K slows axial growth over the study length of two years. Not yet published. Walline, Jeffrey J., Slowing Myopia Progression with Lenses, Contact Lens Spectrum, June

COOKI (Children's Overnight Orthokeratology Investigation) essentially proved that Ortho-K works overnight for children in the 8-11 year old group.
Invest Ophthalmol Vis Sci 2003;44:

SMART (Stabilization of Myopia through Accelerated Reshaping Technologies) A five year study where after each year of wear the patient is allowed to normalize without wearing their molding lenses after which they start wearing their lenses again. Preliminary results show stability after one year.

CANDY (Controlling Astigmatism and Nearsightedness in Developing Youth) showed myopic progression of -.37D per year in normally corrected myopes and -.03D per year in Ortho-K patients. Patients were allowed to normalize at various times during their Ortho-K wear. The graph below summarizes the data.

Over the 3 year period, children who corrected their vision with glasses and soft contact lenses on average had a 1.5 diopter increase of their myopia. The children who wore the Ortho-k correction had a myopic increase of only .37 diopters over the same 3 year period.

Glasses and soft contact lenses Ortho-k lenses
The last two studies (SMART and CANDY) are attempting to answer the question of whether the stabilization is just a temporary phenomenon that would disappear on cessation of lens wear. It appears that the Ortho-K effect is such that patients regress back to their starting point of Ortho-K wear, not partially regress or even progress to where they might have been if not wearing Ortho-K lenses.

The studies are not definitive. It will be a long time before such data is recognized as clinical fact. But the overwhelming evidence at this time is that Ortho-K is a very good alternative for young myopes.

Title: FDA Study Summary of Safety and Effectiveness, Premarket Approval Application (PMA) Abstract: The main objective of this study was to assess the safety and effectiveness of the Euclid Systems Orthokeratology Contact Lenses in the temporary;reduction of myopia, when worn overnight. This investigation was a multi-center study consisting of 9 investigational sites; which included 14 investigators participating. The study was initiated on;September 21, 1998 and ended on June 2, 2000. There were 191 patients (378 ;eyes) enrolled into the study including 4 monocular subjects. There were; ineligible eyes enrolled but not dispensed lenses. The subjects were at least 18;years old. Clinical investigators and investigational sites were selected in an effort to provide sufficient diversity in geographic access, climate and elevation, and urban and rural living for a resultant study population thaL represents the intended ;population to be treated. The study period was 9 months.

The results of the data provided from this clinical study revealed no major complications or slit lamp findings and 12 adverse events which resolved. Additionally, the results show that 95 % of the eyes completing the study in the core group achieved visual acuity of 20/40 or better at nine months and 99% demonstrated a reduction in pretreatment myopia. As shown in Table 15, the results of the clinical study provide reasonable;assurance of the safety and effectiveness of the device for the subject population, refractive conditions and specified wearing modality.

Title: The SMART Study - Clinical Evaluation of Stablizing Myopia by Accelerated Reshaping Technique
DATE: 5 year study in progress. First year results published January 09
LINK: Not published as study still in progress
Barry Eiden, OD, FAAO, Robert L Davis, OD, FAAO, principle investigators Ed Bennett,OD, FAAO, Cary Herzberg, OD, FAAO Michael Lipson OD, FAAO, LaMar Zigler, OD FAAO Doug Becherer, OD, FAAO Bruce Koffler, MD Rob Gerowitz, OD, FAAO, Lisa Wohl, MD " EyeVis"- Eye & Vision Research Institute: Giving Vision Through Research

Abstract: The use of Orthokeratology for overnight wear raises many questions of safety, efficacy and the effects of myopia stabilization. Orthokeratology or corneal reshaping produces a temporary reduction of myopia by changing the shape (flattening) of the cornea, which is elastic in nature. Flattening the cornea reduces the focusing power of the eye, and if the amount of corneal flattening is properly controlled, it is possible to bring the eye into correct focus and compensate for myopia. Upon removal of the contact lens, the cornea retains its altered shape for a period of time. The global prevalence of myopia is increasing significantly in the school age population. It is estimated that one billion of the six billion people in the world are myopic. (3) Not only is the prevalence increasing but the degree of myopia has also increased. The prevalence of myopia in the United States is estimated to be 25%, in India to be 19% and in the Asian nations the rates of myopia are greater than 75%(1,2,3).

Studies have shown that complications from myopia, such as chorioretinal degeneration and retinal detachment will increase with increasing myopia. The application of corneal reshaping or orthokeratology may potentially stabilize the progressive nature of myopia throughout the adolescent years. Additionally, if wearing corneal reshaping lenses controls the progression of myopia, there also may be a reduction in the rates of adverse effects of advancing myopia. The fact that myopia is on the rise indicates that although the wearing of spectacles clears the vision, it does nothing to control the progression of myopia and its adverse effects.

Conclusions: The initial recruitment phase, fitting statistics, and demographics provide the structure for the five year SMART investigation. Initial dispensing data for corneal reshaping test subjects showed a high first lens success rate to achieve 20/20 unaided acuity. Long term results of this study will provide fitting information, myopia progression comparative data, anatomical differences, and subjective responses to each lens modality. 80.5% of the test group were fit able to use the initial empirically fit lens and did not require a lens change.
Year 1 Interim Results: 138 subjects in the test group and 90 from the control group completed the first year. The findings from the first year showed that overall mean prescription change in control group was almost 0.50 diopters whereas there was no change in the test group. The study continues.

 

Title: CLAMP Study - To examine the effects of rigid gas permeable contact lenses on the progression of myopia (nearsightedness) in children.
Abstract: Rigid gas permeable (RGP) contact lenses provide clear, comfortable vision with relatively few ocular health risks and are a standard management option for correcting nearsightedness. While RGP contact lenses are used to correct myopic refractive error, they may also slow the progression of myopia. A definitive study that could provide guidance regarding the effects of rigid gas permeable contact lenses on myopia (nearsightedness) progression may define the standard of care for slowing the progression of myopia in young children. An eye care practitioner first reported that hard contact lenses may slow or stop the progression of nearsightedness in 1956. Other anecdotal clinical reports with similar results soon followed. Previous review papers have suggested that rigid contact lenses slow the progression of myopia in children, and several studies have attempted to prove this.

Two studies in the past twenty years have shown that rigid gas permeable contact lenses slow the progression of nearsightedness in children, however both studies failed to provide proper attention to many important variables. While these earlier works produced intriguing results for scientists and clinicians, they contain many problems that challenge the significance of the studies findings. The faults of the previous studies can be summarized in four categories: 1) high losses to follow-up, 2) inadequate control group, 3) incomplete ocular component measurements, and 4) inadequate or poorly selected entry criteria. Positive results in previous studies also failed to exclude alternate possibilities which may explain why rigid gas permeable contact lenses may slow the progression of myopia.
For example, the studies found that rigid contact lenses slow the progression of myopia and that corneal flattening accounts for some of the treatment effect, but none of the studies was able to definitively answer other mechanisms that may slow myopia advancement. A need for a controlled study of rigid contact lenses which measures all of the components that may affect myopia progression still exists. The CLAMP Study examines all of these components and addresses the problems encountered in previous studies. The CLAMP Study uses a run-in period to enroll only children who are able to adapt to rigid contact lens wear into the study. This decreases the number of children who drop-out of the study because they cannot adapt to rigid contact lens wear. Once children show that they are able to wear rigid contact lenses, they are enrolled in the study and randomly assigned to wear rigid gas permeable contact lenses or soft contact lenses. Both groups are then examined each year for three years to determine which group progresses the most in nearsightedness.
Annual examinations include assessment of the children's ability to focus their eyes, their eye glass prescription, detailed maps of the shape and thickness of their corneas, and the curvature of the lens inside the eye. Their eye glass prescription is determined when the children's eyes are dilated. We examined 222 children for eligibility. Out of the 222 children, 148 were eligible to participate in the run-in period. Of the 148 eligible children, 116 (78.5%) were able to adapt to rigid gas permeable contact lens wear. All of the children were examined at The Ohio State University College of Optometry.
the treatment is used on children. The aim of this paper is to provide a comprehensive guide to practitioners to improve their Orthokeratology practice and minimize unnecessary complications. The fundamental requirement for starting Orthokeratology practice is to have proper education in the area and to equip the practice appropriately.

Title: FERRIS STATE STUDY - SEEOMC- Safety and efficacy of overnight Orthokeratology in myopic children
Date: May 2007 Source: www.sciencedirect.com

Renée Mika, O.D., Bruce Morgan, O.D., Michael Cron, O.D., Josh Lotoczky, O.D., and John Pole, O.D., M.S.; Michigan College of Optometry, Ferris State University, Big Rapids, Michigan.

Abstract: BACKGROUND: This prospective case series was conducted to describe the safety and efficacy of ;Orthokeratology with the Emerald Contact Lens for Overnight Orthokeratology; Euclid ;Systems Corporation, Herndon, Virginia) among young myopes. ;METHODS: Twenty subjects (ages 10 to 16) were enrolled in the 6-month pilot study. Subjects were ;empirically with overnight Orthokeratology lenses and evaluated at 1 day, 1 week, 1 month, 2 months, 3 months, and 6 months.

RESULTS: Sixteen subjects completed the study. The mean baseline spherical equivalent refraction SER) was 06 diopters (D) (0.75). The mean SER at 6 months was 0.16 D 0.38). The mean ;baseline uncorrected acuity was 0.78 (0.28) logarithmic minimum angle of esolution (logMAR) equivalent (20/100 Snellen). The mean logMAR equivalent at 6 months was 0.03 0.12 (20/20 Snellen). On average, 40% of eyes showed some type of corneal staining between the 1-week and 6-month visits. No serious adverse events occurred during the study.

Conclusions: In contrast to previously published studies that reported maximum results at 2 weeks,subjects reached maximum reduction in myopia at the 1-week visit and, on average, obtained a 92.2% reduction in spherical equivalent refractive error at 6 months. This pilot study lends to a growing body of evidence that short-term correction of mild to moderate myopia with overnight orthokeratology is safe and ef cacious in children and adolescents. Optometry 2007;78:225-231
 

Title: Orthokeratology Review and Update
Date: Feb 2006 Source: www.optometrists.asn.au

Helen A Swarbrick PhD School of Optometry and Vision Science, University of New South Wales, Sydney, Australia Clinical Experimetal Optometry
E-mail: h.swarbrick@unsw.edu.au

Abstract: Orthokeratology (OK) is a clinical technique that uses specially designed rigid contact lenses to reshape the cornea to temporarily reduce or eliminate refractive error. This article reviews the history of traditional daily-wear OK (1960s to 1980s) and discusses the reasons for the recent resurgence in interest in the new modality of overnight OK, using reverse-geometry lens designs (1990s to the present). The clinical effecacy of the current procedure is examined and outcomes from clinical studies in terms of refractive error change and unaided visual acuity are summarised.

Onset of the effects of overnight OK lens wear is rapid, with most change after the rst night of lens wear and stability of refractive change after seven to 10 days. Mean reductions in myopic refractive error of between 1.75 and 3.33 D and individual reductions of up to 5.00 D have been reported. There appear to be slight reductions or minimal changes in astigmatism with the use of reverse-geometry lenses and most patients are reported to achieve 6/6 unaided vision or better. The induction of higher order aberrations, in particular, spherical aberration, has been reported and this may affect subjective vision under conditions of low contrast and pupil dilation. Patient satisfaction with overnight OK has been reported as similar to or better than with other popular modalities of contact lens wear.
Available evidence suggests that the corneal changes induced by overnight OK are fully reversible. The refractive effect in OK is achieved by central epithelial thinning and this has raised concerns about compromise of the epithelial barrier to microbial infection. Recent reports of microbial keratitis in the modality are reviewed and the overall safety of the procedure is examined critically. Recent research on stromal contributions to the OK effect, particularly relating to overnight oedema, is summarised. Emerging issues in OK, including myopic control, correction of other refractive errors and permanency of the OK effect, are discussed.

 Title: Microbial Flora of Tears of Orthokeratology Patients, and Microbial Contamination of Contact Lenses and Contact Lens Accessories.
Date: June 2005
Source: www.optvissci.com

BOOST, MAUREEN V. PhD, FIBMS; CHO, PAULINE PhD, FAAO

Abstract: Purpose. The purpose of this study is to determine if there are changes in the ocular flora of overnight orthokeratology (ortho-k) patients, and the levels of contamination of their lenses and lens accessories, and to correlate compliance with levels of contamination.

Method. Normal ocular flora of 41 subjects was determined twice before commencing ortho-k lens wear by culture of the lower conjunctiva. Further specimens were collected on six follow-up visits after beginning lens wear, as were samples from their lenses, cases, and suction holders. A questionnaire on lens care was administered after the fifth visit. Results. Three subjects provided conjunctival samples yielding Staphylococcus aureus on one occasion before lens wear, one being positive for this organism after beginning lens wear. Of 38 subjects yielding no growth or only normal eye flora before use, 28 remained free of ocular pathogens after beginning lens wear. Only four subjects had positive cultures on more than one occasion after lens wear. There was no significant difference in isolation levels of pathogens with lens wear (p = 0.423) culture of 54% of subjects yielded no growth or normal flora only; lenses of 16 subjects yielded potential pathogens, including three subjects contaminated on more than one occasion. Lens isolates did not match the organisms transiently colonizing the eye. Lens case, the most frequently contaminated item, was associated with lens contamination (p < 0.001), the same organism being isolated from both items in 11 subjects. Lens suction holder was less frequently contaminated.Neither lens case nor suction holder contamination was associated with isolates from the eye. Reported good compliance correlated with lack of contamination in all but one subject. The most frequent breaches in the lens care protocol were failure to clean, disinfect, and replace the lens case.
Conclusion. Ocular flora was not altered by ortho-k lens wear over an extended period, and patients remained free of infection. Contaminants identified were generally of a transient nature.Most patients had significant contamination of at least one item, most frequently the lens case. Lens case isolates were significantly associated with those from the lens. The majority of patients reporting good compliance had low or no contamination of their lenses and accessories. (C) 2005 American Academy of Optometry

Title: COOKI - The Children's Overnight
Orthokeratology Investigation Pilot Study
Date: June 2004
Source: www.optvissci.com

Optometry and Vision Science. Walline , Jeffrey j. OD,Phd, FAAO; RAH, Majorie J. OD, PhD, FAAO; Jones Lisa A. PhD, FAAO Lippincott Williams & Wilkins

Abstract: Purpose. Innovations in contact lens materials and designs allow patients to wear contact lenses during sleep to flatten the cornea and temporarily to reduce myopic refractive error and improve unaided visual acuity. We conducted the Children's Overnight Orthokeratology Investigation (COOKI) pilot study, a case series, to describe the refractive error and visual changes, as well as the slitlamp observations associated with overnight orthokeratology in children, over a period of 6 months.

Methods. Twenty-nine 8- to 11-year-old children with myopia between -0.75 and -5.00 D and <-1.50 D corneal toricity were fitted with corneal refractive therapy contact lenses (Paragon Vision Sciences, Mesa, AZ). They were examined within 1 hour of awakening and about 6 hours later at 1 day, 1 week, 2 weeks, 1 month, 3 months, and 6 months after the first night of contact lens wear. At each visit, the logarithm of the minimum angle of resolution (logMAR) visual acuity, manifest refraction, slitlamp examination, and corneal topography were performed.
Results. Twenty-three subjects completed the 6-month study. Three subjects decided not to wear contact lenses, two did not achieve acceptable fits, and one moved from the area. At the 6-month afternoon visit, the mean +/- SD uncorrected high-contrast visual acuity was +0.08 +/- 0.15 logMAR (Snellen equivalent, 20/24), and the mean +/- SD spherical equivalent refraction was -0.16 +/- 0.66 D. The corneas of three-fifths of the subjects showed mild staining at the morning visit, and one-third of the patients showed mild corneal staining at the afternoon visit. The most common type of stain was central punctate staining. No subjects experienced lasting adverse visual effects from cornea-reshaping contact lens wear during the study period.

Conclusions. Overnight cornea-reshaping contact lenses are efficacious for young myopic patients, and no children experienced a serious adverse event during the study. (C) 2004 American Academy of Optometry
 

Title: LORIC - The Longitudinal Orthokeratology Research in Children (in Hong Kong: A Pilot Study on Refractive Changes and Myopic Control
Date: July 2004 ,  Pauline Cho, Sin Wan Cheung and Marion Edwards

Abstract:
Purpose: Myopia is a common ocular disorder, and progression of myopia in children is of increasing concern. Modern overnight orthokera- tology (ortho-k) is effective for myopic reduction and has been claimed to be effective in slowing the progression of myopia (myopic control) in children, although scientific evidence for this has been lacking. This 2 year pilot study was conducted to determine whether ortho-k can effectively reduce and control myopia in children. Methods: We monitored the growth of axial length (AL) and vitreous chamber depth (VCD) in 35 children (7-12 years of age), under- going ortho-k treatment and compared the rates of change with 35 children wearing single-vision spectacles from an earlier study (control). For the ortho-k subjects, we also determined the changes in corneal curvature and the rela- tionships with changes of refractive errors, AL and VCD.

Results: The baseline spherical equivalent refractive errors (SER), the AL, and VCD of the ortho-k and control subjects were not statistically different. All the ortho-k subjects found post-ortho-k unaided vision acceptable in the daytime. The residual SER at the end of the study was -0.18 0.69 D (dioptre) and the reduction (less myopic) in SER was 2.09 1.34 D (all values are mean SD). At the end of 24 months, the increases in AL were 0.29 } 0.27 mm and 0.54 0.27 mm for the ortho-k and control groups, respectively (unpaired t test; p = 0.012); the increases in VCD were 0.23 0.25 mm and 0.48 0.26 mm for the ortho-k and control groups, respectively (p = 0.005). There was signicant initial corneal ;attening in the ortho-k group but no signi;cant relationships were found between changes incorneal power and changes in AL and VCD.

Conclusion: Ortho-k can have both a corrective and preventive/control effect in childhood myopia. However, there are substantial variations in changes in eye length among children and there is no way to predict the effect for individual subjects.
Current Eye Research, 30:71-80, 2005 Copyright:Taylor & Francis Inc. ISSN: 0271-3863 print / 1460-2202 online DOI: 10.1080

Corneal reshaping and myopia progression
J J Walline, L A Jones, L T Sinnott

Accepted 25 February 2009 Published Online First 4 May 2009

Abstract
Background/aims: Anecdotal evidence indicates that corneal reshaping contact lenses may slow myopia progression in children. The purpose of this investigation is to determine whether corneal reshaping contact lenses slow eye growth.

Methods: Forty subjects were fitted with corneal reshaping contact lenses. All subjects were 8 to 11 years and had between −0.75 D and −4.00 D myopia with less than 1.00 D astigmatism. Subjects were age-matched to a soft contact lens wearer from another myopia control study. A-scan ultrasound was performed at baseline and annually for 2 years.

Results: Twenty-eight of 40 (70%) subjects wore corneal reshaping contact lenses for 2 years. The refractive error and axial length were similar between the two groups at baseline. The corneal reshaping group had an annual rate of change in axial lengths that was significantly less than the soft contact lens wearers (mean difference in annual change = 0.16 mm, p = 0.0004). Vitreous chamber depth experienced similar changes (mean difference in annual change = 0.10 mm, p = 0.006).

Conclusion: Results confirm previous reports of slowed eye growth following corneal reshaping contact lens wear.

Orthokeratology for Controlling Myopia:
Clinical Experiences

Two practitioners obtain results similar to that in the literature for controlling myopia with ortho-k.

By Peter A graduate of the University of Alabama at Birmingham School of Optometry, Dr. Wilcox completed a Primary Care residency at Pennsylvania College of Optometry. He is in private practice in
Hayes, Va. He can be reached at doc@wilcoxeye
.com.
A graduate of Illinois College of Optometry, Dr. Bartels is in group practice in Buffalo, N.Y. He can be reached at visioncare@roadrunner.com.
E. Wilcox, OD, & David P.F

For more than 30 years, researchers worldwide have
been studying myopia in children and experimenting
with modalities to slow or stop its progression. Some of the tactics employed have been unpredictable and, at times, inconvenient. For example, the use of atropine eye drops is one of the most successful forms of intervention, but the side effects greatly outweigh the outcomes (Gimbel, 1973; Lee et al, 2006). Spectacles with bifocal or progressive lenses have only minimal effect, and they are cumbersome for active children (Paluru et al, 2005; Leung and Brown, 1999). GP lenses worn during the day may slightly reduce myopia progression but at rates that are of limited value to patients (Walline et al, 2004; Katz et al, 2003). More recently, researchers have turned their attention to the potential of orthokeratology to control myopia in children.

Why Ortho-k Shows Promise Patients undergoing overnight orthokeratology,also known as corneal molding and corneal reshaping, wear custom-made GP contact lenses that Bartels, OD reshape the cornea and provide clear unaided vision during the day. What makes ortho-k a promising treatment for childhood myopia? Researchers feel that hyperopic blur in the equatorial and peripheral retina may be a significant stimulus for increased axial length, which results in myopia progression (Hung et al, 1995; Smith et al, 2005).

Smith and colleagues reported exciting findings and provided intriguing images of axial lengthening (Figure 1) in their 2009 study of monkey eyes, designed to determine whether refractive development in primates is mediated by local retinal mechanisms. They reported:

“The main findings of our study were that hemiretinal form deprivation altered refractive development in a regionally selective manner, typically producing myopia in the treated hemifields of infant monkeys, and that these treatment-induced changes in refractive error were associated with local, region-specific alterations in vitreous chamber depth in the treated hemiretina.”

In our opinion, the clinical significance of this study is powerful, suggesting that eyes may become more myopic due to local deprivation of properly focused light. In the case of a myopic eye, conventional spectacles and contact lenses focus light at the fovea with Figure 1. Hemiretinal form deprivation in infant monkey eyes resulted in myopia development in the treated areas. hyperopic defocus in the midperipheral retina. This relative hyperopia may act as a local signal to stimulate axial elongation of the globe. The axial elongation results in a more myopic condition, which, when corrected, recreates the hyperopic midperiphery.
The cycle ensues and the eye continues to become
more myopic.

It could be theorized that a child who becomes myopic may have had a hyperopic peripheral refractive error that caused the eye to lengthen locally and become myopic. The rationale for the uncorrected myopic eye to progress is that the blur in the macula causes the local lengthening to occur in the macula. Studies are underway to explore these theories. Interrupting this blur-lengthening cycle may be a key factor in the myopia stabilization effect attributed to orthokeratology. Following ortho-k treatment for myopia, the typical molded cornea is flattened centrally and remains unchanged outside of the central 7mm or so. The annular zone, located between 5mm and 7mm, must, therefore, be relatively steeper to align with the unaffected cornea outside of the 7mm zone. This steeper zone results in more clearly focused light in the previously hyperopic midperiphery. Thus, the central zone of flattened cornea provides excellent Snellen acuity, and the red ring (Figure 2) may provide stability in the absolute refractive error. The panretinal stimulation of focused light from orthokeratology may slow myopic eye growth, whereas the spherical and/or aspherical focusing from spectacles and traditional daytime contact lenses is linked with progressing refractive errors from advancing axial lengths. These factors have been the impetus for recent studies of ortho-k for myopia control in children.

Promising Initial Study Results

The Longitudinal Orthokeratology Research in Children (LORIC) study (Cho et al, 2005), a two-year pilot study conducted in Hong Kong, suggests
that ortho-k can have a corrective and preventive/ control effect in childhood myopia. The researchers cautioned, however, that predicting the effect for individual patients is impossible because of substantial variations in eye length changes among
children.

In 2007, Walline reported myopia stabilization via ortho-k in the Corneal Reshaping and Yearly Observation of Nearsightedness (CRAYON) two-year results. In a subsequent study, Walline and colleagues (2009) confirmed previous reports of slowed eye growth following corneal reshaping lens wear.

Also in 2007, Eiden and Davis initiated the Stabilization of Myopia by Accelerated Reshaping Technique (SMART) trial, a five-year ortho-k/myopia
control study of 300 children, ages 8 through 14. Interim results are being prepared for publication.

Clinical Findings

As we followed the literature and read about researchers’ promising results, we began to take a closer look at our own practices, specifically at our young ortho-k patients. Interestingly, we found that our outcomes did more than mirror what the reserchers were reporting. Ortho-k seemed to stop the progression of myopic refractive error in our young patients, although other controlled investigations have reported only a slowing (not stopping) of eye growth and unpredictable results for individuals.

We retrospectively evaluated five patient cases
ages 9 to 15 who were myopic with or without astigmatism for periods ranging from 19 to 62 months. During this period, their myopic/astigmatic spherical equivalent had progressed by 0.46D per year. Their pretreatment spherical refractive errors ranged from –1.00D to –4.25D, and their cylindrical refractive errors ranged from plano to –1.00DC. Before ortho-k lens fitting, the mean spherical equivalent of the 10 eyes was –2.57D. During their 13 to 37 months of
ortho-k wear, these patients either remained in their initial contact lenses or wore duplicate replacements for lost or broken lenses. All five patients achieved 20/20 vision during ortho-k treatment.

We wanted to find out whether there had been any progression in their baseline refractive error. Therefore, we asked them to cease lens wear until their topographies had returned to baseline or for a maximum of 14 days. Because corneal curvature may not return completely to baseline after long-term ortho-k in children (Wu et al, 2009), corneal unmolding was considered complete when patients’ flat simulated K readings were within 0.50D of their pretreatment simulated K readings. A study by Hiraoka and colleagues (2009) confirmed that “the effect of orthokeratology is completely reversible in light of optical quality of the eye and quality of vision as well as refraction and visual acuity.”

During the regression process, we performed noncycloplegic refractions at three- to seven-day intervals until reversal was complete or 14 days had elapsed. The results showed that the patients had essentially returned to their pretreatment refractive error, as the rate of progression of their spherical equivalent refractive error was only 0.03D per year. These are encouraging although anecdotal outcomes, and we are now designing a study to validate them.

Topography is Key to Ortho-k Success Given the promising results of our pilot study, we will continue to recommend our ortho-k for myopia control program (see “Marketing the CANDY
Plan”) and to use the following ortho-k technique.

We fit our ortho-k patients in custom Wave (Wave Contact Lenses) ortho-k lenses. These lenses are software-designed based on topography data, with the Wave Design Software currently optimized for the Keratron family of topographers including the Scout Topographer (EyeQuip), which was used to generate the maps.  Before proceeding with contact lens fitting, we educate and inform all patients and parents about theMarketing the CANDY Plan

Reviewing the clinical histories of some of our young orthokeratology patients has not only
provided encouraging information about the use of this modality for stopping myopia progression in children, but it has also spawned a successful new internal marketing tool in our practices. Over the past year, we devised the “Controlling Astigmatism and Nearsightedness in Developing Youth” program, better known as the CANDY Plan.

The CANDY Plan introduces the concept of orthokeratology to patients and parents through posters and displays in the office, as well as through videos that play in the reception area. Simple statements and intriguing questions such as: “Would you like to participate in our CANDY Plan?” and “CANDY is good for your child’s vision. Ask us why!” are designed to start a dialogue, and people frequently inquire about the CANDY Plan.

With the conversation started, we discuss the details of orthokeratology. We present our graphic (Figure 3), which helps condense a lengthy conversation into a few moments of targeted communication. The myopia stabilization aspect of the therapy is always of great interest to parents. We present the concept of myopia and astigmatism stabilization through
ortho-k as a plan, not a guarantee. We have found, however, that most, if not all, of the children who participate in this process in our practices routinely achieve our predicted goals.
Of course, additional education ensues as needed, but the usually lengthy conversation
about an infrequently recognized vision correction and stabilization process is short and sweet—just like candy.

Figure 3. This graph of our case patients shows that in our practices, ortho-k treatment of myopia has successfully controlled the progression of myopia.

associated pros/cons and risks/rewards of ortho-k treatment. Patients/parents sign the appropriate consent forms once they have read and comprehend the process and the variables. We also inform patients/ parents that although the Wave lenses are similar in design and material to FDA-approved lenses, they are in fact used in an off-label manner (although the lenses we use are now approved for overnight wear under FDA guidelines for ortho-k).

Once we decide to pursue orthokeratology, capturing baseline topography is extremely important. Topography data are the foundation for the custom software-designed Wave ortho-k lenses, so patience and thoroughness are imperative for precise image capture. The lens material used for these patients was Boston XO (Bausch + Lomb). Other considerations when designing an accurate ortho-k contact lens include: refractive error, horizontal visible iris diameter, pupil size, pachymetry, tear quality, and interpalpebral fissure opening. We electronically submit the Wave corneal mold design data to the lab’s CN lathe to manufacture each unique contact lens.

At the dispensing visit, we teach patients proper lens care and handling, including how to apply and remove the lenses. After this training, we apply the lenses and measure unaided visual acuities. Then we have patients recline with their eyes closed for 20 to 30 minutes. At the end of that time, we measure visual acuities and assess the fit with both
white light and fluorescein (Figure 4). We then remove the lenses, measure unaided visual acuities and perform topography.

Our patients and their parents have been satisfied with this experience. Any doubt or resistance disappears as the unaided visual acuities improve after lens removal, despite the brief period of closed-eye wear. We’ve had patients with unaided visual acuity of 20/200 read the 20/40 line after this brief wearing time. We then ask patients to initiate nighttime wear. We’ve found that they routinely enjoy great unaided vision after their first night of wear. Repeating the nighttime wearing process provides them with day time non-surgical freedom from glasses and contact lenses. We typically schedule follow-up visits at one week, one month, and six months, scheduling any additional visits as needed.

Conclusion

Many clinicians are familiar with the benefits of orthokeratology for adults. A significant added value of orthokeratology for young patients, which is supported by a growing number of initial studies, is the possible reduced rate of myopic progression. A recent study (Vitale et al, 2009) reported a 66 percent increase in myopia prevalence over a recent 30-year period. These facts address one of the oldest concerns that parents have held for their children: how to keep their eyes from getting worse every year. We may now have an answer. Learn it, promote it, and provide it. CLS For references, please visit www.clspectrum.com/references.asp and click on document #174.

For more information or shedule for a Ortho-K and CRT evaluation, please call 781-676-2020 for Lexington (MA) office or 603-8988252 for Salem (NH) office.