Fitting of Orthokeratology in the United States: A Survey of the Current State of Orthokeratology : Optometry and Vision Science

Secondary Logo

Journal Logo

ORIGINAL INVESTIGATIONS

Fitting of Orthokeratology in the United States: A Survey of the Current State of Orthokeratology

Lipson, Michael J. OD, FAAO1∗; Curcio, Louise R. MBA2

Author Information
Optometry and Vision Science: July 2022 - Volume 99 - Issue 7 - p 568-579
doi: 10.1097/OPX.0000000000001911
  • Open

Abstract

FU1

Orthokeratology is the process of reshaping the cornea through the use of specially designed reverse geometry contact lenses to temporarily and reversibly reduce refractive error after lens removal. This was first described in the early 1960s by George Jessen.1 Since that time, innovation in design and manufacturing, technology advances in corneal topography, and the use of high-oxygen-transmissibility lens materials have led to the sophisticated, safe, and controlled procedure in practice today. The pattern of wearing orthokeratology lenses only while sleeping was initiated in the early 1990s and attained Food and Drug Administration (FDA) approval in the United States, with the indication for temporary correction of refractive error, in 2002.2 In the almost 20-year time since that milestone, orthokeratology has been extensively studied for its efficacy as a refractive correction,3,4 effect on other visual attributes (contrast sensitivity, aberrations),5–7 impact on vision-related quality of life,8,9 safety, and its efficacy in slowing axial elongation in myopic children.10–14 Whereas orthokeratology has shown successful clinical outcomes and validation from research studies, it has gained popularity with practitioners and patients. Recent interest in orthokeratology has centered around studies demonstrating its effect on slowing axial elongation and slowing the progression of refractive error in myopic children.12,13

One international survey showed that orthokeratology represented 1.2% of all contact lens fits (in the years 2004 to 2017), with significant differences between countries.15 That same survey reported significant growth trends in the fitting of orthokeratology but, again, with significant disparities between various countries. Surveys conducted to date have attempted to quantify the number of practitioners prescribing orthokeratology and the market share these lenses represent. An annual report in the United States on the 2020 contact lens market estimated that orthokeratology represented 3% of the gas-permeable lens market (the gas-permeable lens market was estimated to be 9% of the total contact lens market in an article by Nichols et al. in the January 2021 issue of Contact Lens Spectrum). That same survey found 16% of eye care providers reporting that orthokeratology had significant potential for growth. Relative to managing myopic progression, 39% of respondents to that survey reported practicing myopia management, and of those, 49% felt that orthokeratology or multifocal soft contact lenses were the most efficacious methods.

Data on the orthokeratology market in the United States are scarce and limited in scope. This Fitting of Orthokeratology in the United States (FOKUS) survey was developed to assess detailed fitting and practice trends of practitioners in the United States including practitioners who are actively prescribing and managing orthokeratology patients as well as those who are not.

METHODS

The topics addressed in this survey include characteristics of orthokeratology practitioners and orthokeratology practices, prescribing patterns, patient profile, complications, products/marketing, fees, and market size/growth opportunities. Orthokeratology practitioners generally monitor new orthokeratology patients regularly during initial fitting and the following months to ensure proper fitting, corneal health, and ideal lens positioning during closed-eye conditions. The survey explored fitting, follow-up care, and practice management patterns.

Development

The FOKUS survey was administered using Qualtrics (Qualtrics, Provo, UT) research and analytics software. The survey was in electronic format executed by the respondent on a computer or mobile device. Questions were in the form of multiple choice and selections made by clicking the appropriate boxes online. For select questions, in addition to the multiple-choice responses, survey participants were given the option to respond with “other” and add their response as free text. When a numerical response was requested, responses were entered using a sliding scale or free text. The intended outcome measures of the FOKUS survey involved the general categories of (1) practice and practitioner profiles, (2) clinical prescribing patterns, (3) patient profile, (4) products and marketing, (5) fees, and (6) market size and growth. There were a total of 52 questions. Skip logic and display logic were used such that participants were directed to the next appropriate question based on their responses. Therefore, not all participants were required to respond to all 52 questions.

Distribution

The target audience for the survey was eye care practitioners in the United States of all types and included those who are actively fitting and managing orthokeratology patients as well as those who are not. To achieve participation from a general eye care audience, the survey was distributed via various sources to reach practitioners with a wide range of familiarity with orthokeratology. Distribution to the eye care community was done in April and May 2021 through diversified channels including Jobson Health Care Information, the American Association of Orthokeratology and Myopia Control (AAOMC), the Gas Permeable Lens Institute (GPLI), and ODs on Facebook. Whereas the AAOMC and GPLI groups may have a high percentage of orthokeratology prescribers, both Jobson Health Care Information and ODs on Facebook reach the general eye care community that ensured exposure of the survey to a wide and varied population of eye care providers. An introductory letter was included in these postings with a link to the survey (the survey questions are available via https://drive.google.com/file/d/11dUUAuqpb8H6A5GwgDaFY78fj34BClbH/view?usp=sharing). To incentivize participation, participants were offered the option to enter their e-mail for a randomized drawing to receive one of five $100 gift cards.

In cooperation with various orthokeratology lens companies and brands (Paragon Vision Sciences, Euclid Systems, Bausch + Lomb, AVT, WAVE, iSee, and Eyespace), an estimate of the number of “active” prescribers of orthokeratology lenses was made. This was based on reported numbers of eye care providers who have been certified to prescribe a manufacturer's design and have ordered orthokeratology lenses from that manufacturer in the last year. Results showed that approximately half of the eye care providers who are certified to fit orthokeratology lenses are actively prescribing them. In addition, to help confirm these estimates, we performed an alternate analysis to estimate the number of active orthokeratology practitioners by asking respondents about the total number of orthokeratology patients they have fit, the number of new orthokeratology patients they fit each month, and the number of returning orthokeratology patients they see each month (detailed hereinafter).

Analysis

Statistical analysis of results was performed by the authors with support from Qualtrics. Results and their implications for clinical practice are included in the text hereinafter.

The total number of responses to the survey was 644. Of those, 99 that were received from respondents outside the United States were not included in the analysis. The remaining 545 respondents were used in the data analysis.

It should be noted that detailed analysis of responses for each question showed very consistent responses to most questions with small standard deviations. However, there were two open-ended questions where inputting an individual number may have resulted in isolated “extreme” outlier responses. These may have been due to respondent input error or to misunderstanding the question. For example, one responder who performed six eye examinations per month input 60 new orthokeratology patients per month when the survey median was 2.0. In those rare instances, the extreme outlier responses were not included in the analysis.

RESULTS

Practice and Practitioner Profile

Based on the results, we estimate that there are approximately 3000 eye care providers actively prescribing orthokeratology in the United States. Of the total 545 respondents to the survey, 283 reported that they were actively fitting orthokeratology. This represents just under 10% of the estimated active fitters.

Of the respondents prescribing orthokeratology, 87% were optometrists, 7% were ophthalmologists, and 6% were opticians. They practiced in various types of settings, including 36% in solo practice, 39% in a group practice, 9% in a multidisciplinary practice, 9% in an academic setting, 4% employed by an ophthalmologist, and 3% in a retail setting. All respondents reported they are actively in practice.

Of the total respondents, 283 (52%) reported that they are currently prescribing and fitting orthokeratology in their practice, 76 (14%) had prescribed orthokeratology in the past but have discontinued the practice, and 186 (34%) have never prescribed orthokeratology.

The breakdown for the number of years in practice is shown in Fig. 1. Results for how long respondents have been prescribing orthokeratology are shown in Fig. 2. This demonstrates a significant influx of new orthokeratology fitters, with 32% of respondents having begun prescribing within the last 2 years.

F1
FIGURE 1:
Number of years in practice. Bar chart of the percentage of respondents reporting the number of years they have been in practice.
F2
FIGURE 2:
Years of orthokeratology fitting experience. Pie chart showing the percentage of respondents reporting the number of years of experience they have in fitting orthokeratology.

Total Number of Eye Examinations Performed per Month

The mean ± standard deviation number of eye examinations responders performed each month was 168 ± 114 (range, 50 to 500).

Age of Patients Examined

Of the examinations, responders reported that 38% of those examinations were performed for patients older than 40 years, 30% were 18 to 39 years, 22% were 8 to 17 years, and 10% were 7 years or younger.

New Orthokeratology Patient Visits

When assessing survey data for new patients, the data are not a normal distribution. The median number of new patient visits per month was 2.0 (interquartile range [IQR], 4.0). Upon more detailed data evaluation, there was a significant difference between eye care providers who are frequent prescribers (11 to 20 new orthokeratology patients per month) and those who prescribe less often (2 to 3 new orthokeratology patient visits per month). Approximately 9% of the eye care providers who prescribe orthokeratology account for 90% of the new orthokeratology patient visits. Those top 9% of eye care practitioners have an average of 21 new orthokeratology patient visits per month, whereas the other 90% of practices have 2.6 new orthokeratology patient visits per month.

Returning Orthokeratology Patient Visits

The median number of returning orthokeratology patient visits per month was 5.0 (IQR, 8.0). This is 2.5 times the number of new patient visits per month. Similar to the new patient data, there are significant differences between frequent prescribers and those who prescribe less often. Practitioners who initiated orthokeratology for 20 or more patients per month, representing 15% of the practitioners, had an average of 40 returning orthokeratology patient visits per month. Overall, survey respondents saw a median of seven new and returning orthokeratology patient visits per month.

Total Number of Orthokeratology Patients

Fig. 3 shows the breakdown for respondent's total orthokeratology fits. Overall, 15% of respondents had more than 300 orthokeratology patients in their practice, with this percentage more than doubling to 39% for fitters with 15+ years of experience. Looking at eye care practitioners who had been prescribing orthokeratology for less than 2 years, 60% had prescribed between 1 and 25 patients, and 24% prescribed between 26 and 50 patients. When comparing relatively new orthokeratology fitters to more seasoned fitters, 15% of new fitters versus 88% of fitters with 15 or more years of experience had prescribed 51 or more patients.

F3
FIGURE 3:
Number of orthokeratology patients fit. Percentage of respondents reporting the range of total number of patients they have fit with orthokeratology.

Reason Practitioners Fit Orthokeratology

Of those prescribing orthokeratology, 68% reported prescribing with the intent of managing myopia. Other reasons for fitting showed 19% prescribing orthokeratology as an alternative to glasses or contact lenses worn during the day, 8% prescribing orthokeratology as an alternative to refractive surgery, and 5% as an option for patients who report discomfort with contact lenses worn during the day.

Myopia Management

Relative to how much of the practice is dedicated to myopia management, 35% of respondents reported that myopia management makes up less than 5% of their practice. Thirty-two percent stated that myopia management was 5 to 15% of their practice, and 20% reported that myopia management was 16 to 40% of their practice. Combining those categories shows that two of three respondents have practices with 15% or less of their patients involved in myopia management.

For those practitioners new to orthokeratology (<2 years), 7% were those who had strong myopia management practices dedicating between 41 and 60% of their practice to that specific area, whereas 46% had practices with less than 5% of their practice pertaining to myopia management.

The most prescribed modalities of myopia management were orthokeratology, multifocal soft contact lenses, prescribing less screen time, increased hours outdoors, and atropine drops. Much less frequently mentioned were multifocal spectacles and vision therapy. When asked to list their “preferred” method of myopia management, 62% listed orthokeratology, 11% multifocal soft contact lens, and 10% orthokeratology plus atropine. The remaining 17% included five additional responses that were mentioned by 0.5 to 6% of respondents.

Axial Length Measurement

Relative to myopia management, 53% of respondents reported that they measured axial length. The measurement of axial length was most often performed with optical biometry (73%), followed by ultrasound (21%) and other (6%). The group of 46% who do not measure axial length was asked the reason they chose not to. Reasons reported were “don't have the equipment” (51%), “equipment is too costly” (20%), and “don't feel it is necessary” (7%). It is significant to note that 22% of those who did not measure axial length report that they monitor myopia progression with refraction (not specified as to whether this is subjective, objective, cycloplegic, or noncycloplegic).

“Why Don't You Prescribe Orthokeratology?”

For those not prescribing orthokeratology, the top reasons selected were the following: (1) high cost for patients (33% of respondents), (2) “I feel patients aren't interested” (31% of respondents), and (3) too much chair time (29% of respondents). Less commonly selected reasons included the following: “it's not been proven effective” (6% of respondents), “I'm not comfortable having the discussion” (7% of respondents), and “not FDA indicated for myopia progression” (6% of respondents).

Opinion on Why More Doctors Are Not Prescribing Orthokeratology

All respondents were asked the reasons they felt more eye care practitioners were not fitting orthokeratology. This was an open-ended question, with the most common responses being time, learning curve, cost, safety concerns, and unfamiliarity with gas-permeable materials.

Clinical Prescribing Patterns

Fitting Method

Empirical and Diagnostic Combined

Initial diagnostic lens parameters are determined via a fitting nomogram or calculator followed by assessment of that diagnostic lens on the eye to confirm accuracy before ordering. Thirty-two percent of the respondents reported that this was their preferred technique.

Topography-based Software

Captured topography data are uploaded to a design software program to automatically or custom design the parameters of the lens. Twenty-seven percent of the respondents reported that this was their preferred technique.

Empirical

Examination data are sent to the laboratory/manufacturer who designs the lens based on the information submitted from manual readings or a topography printout. Twenty-three percent of the respondents reported that this was their preferred technique.

Diagnostic Evaluation

This method involves the practitioner assessing the fit of a known lens on the eye with the use of sodium fluorescein. Changes in specifications can be made until the practitioner is satisfied with the fitting characteristics. Fifteen percent of the respondents reported that this was their preferred technique.

Patient Profile

Patient Characteristics from Respondents Who Prescribe Orthokeratology

Patient Age

Six years of age was the youngest age that 27% of respondents reported they were comfortable prescribing orthokeratology for. Another 26% reported 7 years as the youngest age, and 17% reported 8 years as the youngest age. Therefore, 70% of the respondents would fit an 8-year-old, whereas 7% reported that they were only comfortable fitting children 10 years and older. However, in practice, when asked the actual age range of their patients when starting orthokeratology, 12% were younger than 8 years, 49% were 8 to 13 years old, 24% were 14 to 18 years old, and 15% were older than 18 years.

Refractive Error of the Patient

Relative to refractive error, 19% of practitioners stated that they fit patients with up to 5.00 D of myopia, 24% with up to 6.00 D of myopia, 12% with up to 7.00 D, and 14% with up to 8.00 D. Combining the 6.00, 7.00, and 8.00 D means that 50% would fit patients with up to 6.00 D of myopia. Other fitting criteria mentioned by 13% of respondents were only fitting patients up to the FDA guidelines,2 10% reported that they have no limit to the level of myopia for which they prescribe orthokeratology, and 8% reported up to 4.00 D.

Refractive and Corneal Astigmatism

When participants were asked about the highest refractive astigmatism for which they would prescribe orthokeratology, 24% stated that 1.50 D was the highest for which they prescribe, 28% stated up to 2.00 D, 18% up to 3.00 D, 7% up to 4.00 D, 5% no limit, and 11% up to the FDA guidelines2 to the amount of refractive astigmatism they will treat with orthokeratology. Therefore, if a patient with 2.00 D of refractive astigmatism presented for orthokeratology, 53% of our respondents would prescribe orthokeratology for that patient.

Corneal Astigmatism

Results for the same question about corneal astigmatism were quite similar, with 24% prescribing for up to 1.50 D of corneal astigmatism, 26% up to 2.00 D, 18% up to 3.00 D, 6% up to 4.00 D, 5% no limit, and 13% up to the FDA guidelines (even though there are no FDA guidelines for the amount of corneal astigmatism).2

Toric Orthokeratology Designs

Ninety-five percent of respondents reported that they prescribe toric designs (5% report never prescribing toric designs). Reasons for using toric designs include large elevation difference noted on topography (23%), refractive astigmatism >1.25 D (11%), and corneal astigmatism >1.25 (24%). These are proactive prescribing habits that indicate that the initial lenses ordered are intended to address the fitting challenges presented by these cases. In contrast, 38% of the respondents prescribe toric designs in a reactive prescribing pattern, after initially fitting a spherical design that does not center well (21%) or shows a poor response to reduction of astigmatism (17%).

Adults versus Children

For children versus adults, 57% prescribed the same orthokeratology designs for both, and 43% stated that they prescribe different designs for children than for adults.

Orthokeratology Lens Replacement

Annual lens replacement was recommended by 64% of respondents, whereas 17% recommend replacement at the discretion of the doctor, 11% every 2 years, and 6% every 6 months. The remaining 2% recommended replacing lenses only when a patient requests a new set.

Follow-up Care Schedule

After the initial fitting period (the length of this period varies with each practitioner), 46% of respondents recommended follow-up visits every 6 months for their orthokeratology patients, 32% recommended follow-up every 3 months, and 19% annually. The remaining 3% recommended follow-up care on some “other” schedule.

Duration/Discontinuation of Orthokeratology Treatment

Results showed that the mean length of time orthokeratology patients undergo the process estimated by practitioners is almost 8 years (7.88 ± 4.2 years), with a reported range of 1 to 25 years. Most patients initiated orthokeratology treatment as young children. When asked about patients who may discontinue treatment before age of 18 years, 41% of respondents reported that discontinuation was occasional (11 to 25% of their patients), whereas 30% reported that discontinuation before age of 18 years was rare (1 to 10% of their patients). Of the patients who did discontinue, the most common reasons reported were inability to sleep, difficulty with application and removal, safety concerns, and inability to wear lenses for enough hours. It is notable that vision, cost, and comfort were not among the top reasons stated for discontinued use.

Complications

Results are shown in Fig. 4. The most frequently reported complication was corneal staining, with 58% reporting it occasionally, 20% reporting it rarely, and 20% reporting it often.

F4
FIGURE 4:
Complications with orthokeratology. Bar chart showing the frequency of reported complications. The most commonly reported complication is corneal staining with 20% reporting it rarely, 58% reporting seeing it occasionally, and 20% reporting it often.

Regarding microbial keratitis, the most serious complication, in the last 5 years, 44% reported that they have seen no cases of microbial keratitis, 26% reported having seen one documented case, and 17% reported having seen two cases. Posed as a different question, 86% of respondents reported that microbial keratitis was rarely or never seen. Follow-up on cases of microbial keratitis revealed various clinical observations. Thirty percent reported that microbial keratitis patients temporarily discontinued orthokeratology wear and returned to wear after resolution, and 20% permanently discontinued orthokeratology. Of all the respondents who prescribe orthokeratology and saw a case of microbial keratitis, 3% reported that it resulted in a loss of best-corrected visual acuity.

Products and Marketing

Number of Designs/Brands Prescribed

Analysis of the number of orthokeratology brands respondents prescribe showed that 23% of respondents prescribe one brand of orthokeratology lens, with the remaining 77% prescribing more than one design. Details of the others showed that 40% prescribe two brands, 20% prescribe three brands, and 12% prescribe four brands of orthokeratology designs.

Brand Preference

The frequency of the brand/design mentioned as one of their top three brands prescribed is shown in Fig. 5 and includes 19 different brands.

F5
FIGURE 5:
Preferred brands/designs of orthokeratology lenses prescribed. Bar chart showing the frequency of the brand of orthokeratology lens reported as one of the top three brands that respondents prescribe. Respondents had the option to respond with one, two, or three brand names. The graphic includes the brands mentioned most frequently. “Other” brands included OrthoTool, RGP Designer, Practitioner's own design, Miraclens, VIPOK, BE/BeFree, CKR, Valley, TruForm, and X-Cel.

Lens Purchasing

Practitioners ordered orthokeratology lenses from multiple companies. Respondents reported ordering orthokeratology lenses most commonly from Paragon (58%), GP Specialists (30%), Euclid (22%), and Art Optical (20%). Other companies mentioned were ABB (18%), Custom Craft (12%), Bausch + Lomb (10%), and AVT (6%).

Corneal Topography Equipment

Corneal topographer brand preferences are shown in Fig. 6 and included 14 different brands.

F6
FIGURE 6:
Preferred brand of topographer used for orthokeratology. Distribution of responses to the question of which one topographer is the brand respondents prefer for fitting and managing orthokeratology patients. The graphic includes the brands reported most frequently. The “other” category included the following brands: Topcon Aladdin, Essilor, Topcon, OPD Scan, Oculus Orbscan, EH-300, Zeiss (not Atlas), Tomey, and Oculus EasyGraph.

Orthokeratology Training/Education

Relative to education and training for fitting and prescribing orthokeratology, the sources for orthokeratology training and education (from most often to less often) were (1) on their own/experience with patients (50%), (2) webinars (48%), (3) manufacturer (43%), (4) orthokeratology meetings (41%), (5) optometry school (36%), (6) fitting workshops (36%), (7) company consultants (33%), and (8) colleagues (25%). Respondents checked all that applied, resulting in the total percentage being greater than 100%.

Sources for Increasing Knowledge of Orthokeratology and Myopia Management

The top sources for clinical knowledge were the AAOMC (62%), GPLI (37%), American Academy of Optometry (27%), and the American Optometric Association (25%). Organizations/companies that offer the best overall support for the practice of orthokeratology and myopia management were queried. Specific mentions were Paragon (34%), AAOMC (14%), Euclid (11%), and CooperVision (9%). GP Specialists, Art Optical, ABB, and Eyespace were 3% each. Other companies accounted for 20% of the responses, with no answer being mentioned more than three times.

Marketing

The most mentioned first marketing method was word-of-mouth referral, which was reported 61% of the time. E-mail blasts, office Web sites, and in-office marketing were also important (Fig. 7). Social media, direct mail, and paid search were selected but not selected as primary tools.

F7
FIGURE 7:
Orthokeratology marketing methods. Bar chart displaying the results of the most common methods for marketing orthokeratology. Respondents were asked to list their top three methods of marketing.

Fees

The data show that the overwhelming fee structure preference was to bundle services, office visits, and lenses into a global fee, with 90% of doctors choosing that option. However, not all bundles are created equal. The distribution of fee structure showed that 47% charged the same bundled fee for all patients, and 43% have a tiered fee schedule that varied based on complexity of the case. Only 10% of doctors charged for fitting visits and lenses separately.

Year 1 Fees

Table 1 represents the 90% of respondents who bundle their fees. Respondents selected the fee by moving a slider between $0.00 and 4500 rather than selecting from a set range of numbers.

TABLE 1 - Bundled fees
No. pairs in bundle Percentage of respondents Avg. bundled fee SD
All 100% $2139 $705
1 Pair 62% $2072 $613
2 Pairs 33% $2228 $847
3 Pairs 5% $2412 $606
The table lists the average bundled fee for the first year of orthokeratology services based on the number of pairs of lenses provided. Avg. = average; SD = standard deviation.

A tiered fee schedule based on case complexity (degree of myopia, degree of astigmatism, or taking over a previous case with inadequate results) was offered by 43% of respondents. For respondents who do not bundle their fees and charged separately, results for mean fees were as follows: evaluation, $168 ± 121; fitting visits, $220 ± 131; follow-up visits, $119 ± 83; and visits after 1 year, $147 ± 120.

Year 2 Fees

Year 2 fees were lower than the initial year. Similar to year 1 fees, respondents selected the fee by moving a slider between $0.00 and 4500 rather than selecting from a set range of numbers.

Responses varied widely with an average of $866 ± 506 and ranged from $361 to 1373. The median was $772 (IQR, $655) and may be a more representative data point. The number and interval of these visits were not specified.

Lens Replacement Fees

The mean fees for orthokeratology lens replacement when not included in the bundled fee are shown in Table 2. Respondents selected the fee by moving a slider between $0.00 and 500.

TABLE 2 - Orthokeratology lens fees
Average SD
Original pair (not in bundle) $442 $175
Spare pair $382 $155
Replacement pair $397 $150
Replacement lens $233 $90
The table shows the average fees for orthokeratology lenses when not included in a bundled fee. SD = standard deviation.

Potential Fees Generated with Orthokeratology

Using fees from the survey data, a new orthokeratology patient may generate between $6838 and 8248 of revenue over an average span of wear. This assumes 7.8 years of orthokeratology wear (as determined from the survey results), 8 years of eye examinations, a bundled fee of $2139 ± 705 in the first year, and subsequent years with median bundled fees of $772 (IQR, $655). This translated to an average profit per patient from $4822 and 6232 over an 8-year period. (Other assumptions include orthokeratology lens acquisition cost of $240/pair, the year 1 fee included 1.4 pairs of lenses, and year 2 and beyond fee included 1 pair of lenses.)

Survey data showed that 52% of the respondents have fit 51 or more orthokeratology patients. Using 50 orthokeratology patients as an example, those patients may generate between $341,900 and 412,400 in gross revenue and between $241,100 and 311,600 in gross profit over the 8 years of wear.

Market Size and Growth Opportunity

Number of Eye Care Practitioners Prescribing Orthokeratology

The estimated number of eye care practitioners actively prescribing orthokeratology was determined by using information provided by orthokeratology manufacturers combined with the survey data.

Two methods were used to estimate the number of active prescribers. In the first method, the number of active certifications by brand was divided by the brand preference percentages from the survey to arrive at an estimated number of eye care practitioners prescribing orthokeratology. The final estimate of 3000 eye care practitioners was an average of the estimated eye care practitioners by brand. To verify the number, in the second calculation, the total number of active certifications was weighted based on the number of designs prescribed to account for an eye care practitioner certified in more than one design. This final number was similar to the 3000 estimate from the first method. That number (3000) represents 7.6% of the 39,420 U.S. optometrists16 who are prescribing orthokeratology. (Optometrists represented 87% of the respondents to our survey.)

Growth Outlook for Those Currently Fitting Orthokeratology

The outlook of practitioners currently prescribing orthokeratology was toward growth, with 56% of the respondents anticipating growth over the next 12 months (42%, slight growth; 14%, significant growth), whereas only 8% expect a slight or significant decrease.

Growth Outlook for Those Not Currently Fitting Orthokeratology

Respondents were also asked about their plans relative to orthokeratology fitting in the future. Of those who were not currently fitting orthokeratology (those who have never fit/prescribed and those who have fit/prescribed but stopped), 54% have no intention of prescribing orthokeratology going forward, and 46% plan to start fitting within the next 2 years. Notably, looking only at those who have fit in the past and discontinued, approximately two-thirds of them plan to restart fitting and prescribing orthokeratology within the next 2 years.

DISCUSSION

Data on the orthokeratology market in the United States are scarce and limited in scope. This is the first survey published to assess such a detailed level of practitioners' attitudes, fitting habits and usage patterns relative to the process of orthokeratology, and the clinical profile of orthokeratology patients. A concerted effort was made to distribute the survey to a diverse group of eye care practitioners. Respondents were located throughout the United States. Results of this survey provide a knowledge base about those prescribing orthokeratology, their reasons for prescribing, and the patients they are prescribing it for.

Diagnostic equipment is important to the practice of orthokeratology. First, corneal topography is necessary to fit and monitor orthokeratology patients. This is supported by professional organizations such as the AAOMC, orthokeratology lens manufacturers, and a consensus of experienced orthokeratology practitioners (M.J. Lipson, OD, personal communication, September 2021). Next, biometry devices to measure axial length are becoming more commonly used by practitioners involved with myopia management. A high majority of respondents in this study reported that slowing axial elongation and myopia progression was the primary reason for recommending and initiating orthokeratology. Numerous studies show that children undergoing orthokeratology experience less axial elongation than those wearing traditional spectacle lenses and/or traditional soft lenses.17–25 This was reflected in our finding that 53% of those fitting orthokeratology are measuring axial length.

Results showed that most eye care providers are comfortable initiating the process of orthokeratology at a young age. It is interesting to note that more than 80% of our respondents state that they will prescribe orthokeratology for children 8 years or younger, yet only 12% report that the actual age of their patients starting orthokeratology is younger than 8 years. It is unknown as to whether this is due to practitioner hesitancy to start these patients on orthokeratology or if it may be due to patient/parent resistance. This is a good question for a follow-up survey.

Patient loyalty is a common topic discussed in eye care. As reported, orthokeratology patients typically continue the process of using orthokeratology for almost 8 years. Most wearers continue with the same practitioner during that time (M.J. Lipson, OD, personal communication, September 2021). Respondents reported that it is uncommon for patients to discontinue orthokeratology before the age of 18 years. Notably, the most common reasons for discontinuation include inability to sleep, difficulty with application and removal, safety concerns, and inability to wear lenses for enough hours. With soft contact lenses, vision, cost, and comfort are reported to be the most common reasons for discontinuation.26 These reasons were not among the top reasons for discontinued use of orthokeratology.

With children being the primary demographic for orthokeratology, it is reassuring to see that, similar to large-scale studies, corneal staining is the most commonly reported complication of orthokeratology. Adverse events with orthokeratology have been reported in the literature to occur in low frequency.17,27–31 The large majority of adverse events reported are minor and resolve without complications. Respondents indicated that corneal staining is the only adverse response observed often. Serious adverse events such as microbial keratitis are reported rarely. In those who saw a case of microbial keratitis, 3% reported that it resulted in a loss of best-corrected visual acuity. This result correlates well with the published literature. Bullimore et al.27 found that approximately only 3% of cases of microbial keratitis in orthokeratology wearers result in loss of best-corrected visual acuity.

Fees for orthokeratology services are higher than those traditionally found in a general optometric practice. (As a reference, the Essilor MBA survey published a detailed analysis of fees related to spectacle wearers. Among independent optometry practices, the median retail sale for a pair of eyeglasses is $240, and the median examination fee for direct pay is $135.)32 Compared with soft contact lenses, prescribing orthokeratology involves certification, additional training, more chair time, and multiple visits. Orthokeratology fees reflect the higher level of expertise associated with orthokeratology and the greater number of follow-up visits required. Higher profit margin may also be associated with orthokeratology services. This may be justified because of the assumption of greater risk and responsibility for the patients' overall visual status and the patient management complexities.

Strengths of the FOKUS study include the following:

  • (1) The varied population of eye care providers who were solicited for the study and the profile of the respondents. The respondents included practitioners who were recent graduates and those in practice for many years. In addition, just over half of the respondents were currently fitting and prescribing orthokeratology. Just under half were those who had never fit orthokeratology and those who had fit in the past and discontinued fitting.
  • (2) The survey covered a broad range of topics assessing details about the profile of orthokeratology fitters, profile of the patients being fit, fitting habits, lens designs being prescribed, preferred equipment, fees charged, attitudes toward orthokeratology, and future plans for prescribing orthokeratology.
  • (3) The number of respondents was high and represented a significant population of eye care practitioners who are involved in orthokeratology. In comparison, a scientific study from 2017 data published in 2021 sent surveys to 4050 randomly sampled optometrists from a population of 45,033 listed in the American Optometric Association's Optometry Master Data File database.33 They received a total of 1158 responses that represented 2.6% of the total number. In addition, a scientific study on surveys showed that the sample size estimation to result in valid findings for a population of 3000 is 249.34 The number of active-fitter responses in this study was 283, which is well above that. The profile of respondents to the FOKUS survey was balanced and reflected the overall profile of experiences of the eye care community throughout the country. Just over half of the respondents were currently fitting and prescribing orthokeratology. Therefore, results about attitudes toward orthokeratology were not based on analysis of only those who were actively prescribing the process.

Weaknesses of the FOKUS survey include the following:

(1) The survey was somewhat lengthy, requiring 12 to 14 minutes to complete. Not all those who started the survey completed it.

(2) As with any survey, in retrospect, there are additional details that may have been informative, such as specifics about reasons for choosing brand/design, fees charged after the initial fitting (future studies could include more detailed questions to clarify fees beyond the first year), details about frequency of axial length measurement, and barriers to getting started in orthokeratology.

(3) There was a potential for responder bias with those who responded to the survey having a particularly positive or negative attitude toward orthokeratology. Those who had no feelings about orthokeratology may not have been interested enough in the topic to respond.

(4) There is also the potential for some recall bias, that is, systematic reporting error that may occur when participants do not remember previous events or experiences accurately or omit details. However, because this could sway overall results in either direction, this type of error may not be significant. The number of practitioners actively prescribing and fitting orthokeratology in the United States is approximately 3000, which represents approximately 8% of the total number of practicing optometrists (87% of respondents were optometrists). Fitting and prescribing of orthokeratology are a specialty service requiring training, certification, and certain basic equipment and are associated with significant initial cost to the patient. Even with these growth challenges, results showed that practitioners not currently fitting orthokeratology are planning to start, and those who are already fitting plan on increasing their prescribing of orthokeratology. Of those who are currently fitting orthokeratology, almost one-third of respondents have been fitting orthokeratology for 2 years or less, and approximately one in four have been fitting orthokeratology for more than 15 years. In addition, 36% have been in practice for 10 years or less, whereas 44% have been in practice for more than 20 years. Results of the FOKUS survey demonstrated a growth trend for orthokeratology, with the potential for significant growth in individual practices and in the overall orthokeratology market.

These survey results are important for all individuals and entities involved in the orthokeratology market. For practitioners currently fitting orthokeratology and those planning to start, information on patient profile, lens designs, equipment, fees, and marketing is critical for future planning and practice management. For manufacturers, information on practice habits is useful for creating business strategies involving orthokeratology fitting, lens design, problem solving, and educational initiatives. Optometry schools and academia can use the survey data for creating their future curricula and research studies. Issues raised in this survey may help identify specific topics that need more detailed research. Finally, the publishing community may use the results to target topical articles to their audience in this growing field.

The orthokeratology market is evolving and changing quickly. There is an unmet need to monitor the current market and future trends of product development, fitting habits, safety, and public education. Monitoring and assessment of the field could be undertaken through the use of a registry. Alternatively, a cooperative alliance between manufacturers and practitioners (or associations of practitioners such as the AAOMC) may be helpful in tracking orthokeratology prescribing. FOKUS 2, a follow-up survey, will be conducted in the future.

Considerations for future orthokeratology market surveys might include a variety of attributes: (1) expansion of the survey to other countries or regions such as Canada, Europe, Central/South America, Asia, and Australia/New Zealand; (2) developing a more detailed section on how eye care practitioners might more easily overcome barriers to getting started with orthokeratology; (3) expanding efforts with manufacturers to track the number of practitioners who are new to orthokeratology fitting and those who are actively fitting; (4) performing a similar survey directed only to ophthalmologists; and (5) performing an orthokeratology survey targeting the end users, patients, and parents.

Overall, orthokeratology is a small but growing segment of the overall contact lens market. Its significant role as a means of slowing axial elongation and myopia progression for children continues to fuel growth. Growth opportunities for orthokeratology are evident by interest in initiating the process by those not currently fitting and intention to increase fitting by those who are currently fitting. Potential changes in the orthokeratology market may be influenced by other factors as well. These include development of new designs, refinement of fitting techniques (topography-based or empirical systems, etc.), education of existing practitioners, increased emphasis in optometry schools, greater public and general practitioner awareness of orthokeratology, increasing awareness of the potential complications associated with myopia, and regulatory changes associated with orthokeratology related to slowing axial elongation.

These survey results are from eye care practitioners in the United States who were fitting and managing orthokeratology patients and those who were not. Results provide a profile of orthokeratology prescribers, patients, and the overall market. Results of the FOKUS survey provide a baseline of metrics to compare for future orthokeratology data.

REFERENCES

1. Jessen GN. Orthofocus Techniques. Contacto 1962;6:200–4.
2. U.S. Food and Drug Administration (FDA), Center for Devices and Radiological Health. Summary of Safety and Effectiveness, Premarket Approval Application Supplement #P870024/S43. January 18, 2002. Available at: https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpma/pma.cfm?id=P870024S043. Accessed September 17, 2021.
3. Johnson KL, Carney LG, Mountford JA, et al. Visual Performance after Overnight Orthokeratology. Cont Lens Anterior Eye 2007;30:29–36.
4. Nti AN, Berntsen DA. Optical Changes and Visual Performance with Orthokeratology. Clin Exp Optom 2020;103:44–54.
5. Berntsen DA, Barr JT, Mitchell GL. The Effect of Overnight Contact Lens Corneal Reshaping on Higher-order Aberrations and Best-corrected Visual Acuity. Optom Vis Sci 2005;82:490–7.
6. Chang CF, Cheng HC. Effect of Orthokeratology Lens on Contrast Sensitivity Function and High-order Aberrations in Children and Adults. Eye Contact Lens 2020;46:375–80.
7. Lau JK, Vincent SJ, Cheung SW, et al. Higher-order Aberrations and Axial Elongation in Myopic Children Treated with Orthokeratology. Invest Ophthalmol Vis Sci 2020;61:22.
8. McAlinden C, Lipson MJ. Orthokeratology and Contact Lens Quality of Life Questionnaire (OCR-QoL). Eye Contact Lens 2018;44:279–85.
9. Zhao F, Zhao G, Zhao Z. Investigation of the Effect of Orthokeratology Lenses on Quality of Life and Behaviors of Children. Eye Contact Lens 2018;44:335–8.
10. Nichols JJ, Jones L, Morgan PB, et al. Bibliometric Analysis of the Orthokeratology Literature. Cont Lens Anterior Eye 2021;44:101390.
11. Villa-Collar C, Álvarez-Peregrina C, Hidalgo Santa Cruz F, et al. Bibliometric Study of Scientific Research on Overnight Orthokeratology. Eye Contact Lens 2018;44:344–9.
12. Efron N, Morgan PB, Jones LW, et al. Topical Review: Bibliometric Analysis of the Emerging Field of Myopia Management. Optom Vis Sci 2021;98:1039–44.
13. Lipson MJ, Brooks MM, Koffler BK. The Role of Orthokeratology in Myopia Control: A Review. Eye Contact Lens 2018;44:224–30.
14. Bullimore MA, Johnson LA. Overnight Orthokeratology. Cont Lens Anterior Eye 2020;43:322–32.
15. Morgan PB, Efron N, Woods CA, et al. International Survey of Orthokeratology Contact Lens Fitting. Cont Lens Anterior Eye 2019;42:450–4.
16. U.S. Bureau of Labor Statistics. Occupational Employment and Wage Statistics: May 2019 National Occupational Employment and Wage Estimates; 2019. Available at: https://www.bls.gov/oes/2019/may/oes_nat.htm#29-0000. Accessed May 17, 2022.
17. Vincent SJ, Cho P, Chan KY, et al. CLEAR—Orthokeratology. Cont Lens Anterior Eye 2021;44:244–69.
18. Cho P, Cheung SW. Protective Role of Orthokeratology in Reducing Risk of Rapid Axial Elongation: A Reanalysis of Data from the ROMIO and TO-SEE Studies. Invest Ophthalmol Vis Sci 2017;58:1411–6.
19. Bullimore MA, Richdale K. Myopia Control 2020: Where Are We and Where Are We Heading?Ophthalmic Physiol Opt 2020;40:254–70.
20. Cho P, Cheung SW. Retardation of Myopia in Orthokeratology (ROMIO) Study: A 2-year Randomized Clinical Trial. Invest Ophthalmol Vis Sci 2012;53:7077–85.
21. Walline JJ, Lindsley KB, Vedula SS, et al. Interventions to Slow Progression of Myopia in Children. Cochrane Database Syst Rev 2020;CD004916.
22. Si JK, Tang K, Bi HS, et al. Orthokeratology for Myopia Control: A Meta-analysis. Optom Vis Sci 2015;92:252–7.
23. Sun Y, Xu F, Zhang T, et al. Orthokeratology to Control Myopia Progression: A Meta-analysis. PLoS One 2015;10:e0124535.
24. Hiraoka T, Sekine Y, Okamoto F, et al. Safety and Efficacy following 10 Years of Overnight Orthokeratology for Myopia Control. Ophthalmic Physiol Opt 2018;38:281–9.
25. Santodomingo-Rubido J, Villa-Collar C, Gilmartin B, et al. Myopia Control with Orthokeratology Contact Lenses in Spain: Refractive and Biometric Changes. Invest Ophthalmol Vis Sci 2012;53:5060–5.
26. Sulley A, Young G, Hunt C. Factors in the Success of New Contact Lens Wearers. Cont Lens Anterior Eye 2017;40:15–24.
27. Bullimore MA, Ritchey ER, Shah S, et al. The Risks and Benefits of Myopia Control. Ophthalmology 2021;128:1561–79.
28. Liu YM, Xie P. The Safety of Orthokeratology—A Systematic Review. Eye Contact Lens 2016;42:35–42.
29. Bullimore M, Sinott LT, Jones-Jordan LA. The Incidence of Microbial Keratitis with Overnight Corneal Reshaping Lenses. Optom Vis Sci 2013;90:937–44.
30. Lipson MJ. Long-term Clinical Outcomes for Overnight Corneal Reshaping in Children and Adults. Eye Contact Lens 2008;34:94–9.
31. Hu P, Zhao Y, Chen D, et al. The Safety of Orthokeratology in Myopic Children and Analysis of Related Factors. Cont Lens Anterior Eye 2021;44:89–93.
32. Essilor of America, Inc., ECP University. Key Metrics: Assessing Optometric Practice Performance & Best Practices of Spectacle Lens Management Report. Management and Business Academy (MBA); 2018. Available at: https://ecpu.com/media/wysiwyg/docs/ECPU_MBA_KeyMetricsReport_2018.pdf. Accessed January 9, 2022.
33. Heath DA, Spangler JS, Wingert TA, et al. 2017 National Optometry Workforce Survey. Optom Vis Sci 2021;98:500–11.
34. Adam A. Sample Size Determination in Survey Research. J Sci Res Reports 2020;26:90–7.
Copyright © 2022 American Academy of Optometry