Once considered a niche discipline, orthokeratology has evolved, largely due to advances in rigid lens materials and designs and improved access to instrumentation that allow better corneal profiling and lens ordering and evaluation. In recent years, the use of orthokeratology as a means of myopia management has repositioned the technique well within eye care practice, and increasing numbers of ECPs are looking to develop their skills in this area.
The aim of this sixth interactive CPD exercise was to encourage discussion about orthokeratology. In particular, to start thinking about how the technique might be introduced to a practice where it had not been previously prescribed.
Case Scenario
Two young, spectacle-wearing parents bring their nine-year-old son to see you. Their main concern was that their son, who had been confirmed to be myopic one year previously, would continue to need ‘stronger and stronger glasses’ at every future eye check. His refractive error is as follows:
- R: -1.25 / -0.25 x 175 (6/5)
- L: -1.00 / -0.25 x 180 (6/5)
This equates to approximately a half dioptre myopic progression over the last 12 months. Concerns about this progression and having read about possible adverse effects of myopia upon eye health, the parents are keen to know more about myopia management. Consider the following questions for your discussion:
- When asked about myopia management, would you describe all the various methods shown to have some effect? If not, explain why.
- The parents have been told about orthokeratology and ask your advice about the technique. What are the pros and cons and might it be suitable for this child?
- In terms of equipment, what do you consider the minimum instrumentation to be able to undertake orthokeratology successfully?
Your Discussions
As might be expected, responses revealed a wide range of experiences with orthokeratology, though the majority implies that, as yet, it was a technique they had not undertaken in practice. One of your comments struck a chord, reminding me of the great efforts we used to make to avoid corneal moulding when fitting hard lenses and how this made orthokeratology seem, somehow, wrong. ‘As a practitioner from the 1980s, and one who spent some considerable time rehabilitating corneas of PMMA wearers, and refitting them with, then, more modern higher Dk materials, I carry an inevitable bias against intentionally reshaping corneas.’
Another response betraying a degree of caution regarding orthokeratology was: ‘The thought of distorting a natural tissue structure, particularly on a child has always made us sceptical about this sort of treatment and we certainly don’t go down the atropine road. Better to encourage time outdoors, which a lot of these sporty children do anyway.’
Management Options
Most respondents agreed that it is important to discuss all valid management options with patients. Here are two examples.
‘As the parents are myopes, even if they did not request information about myopia management, we would offer this as a matter of course. This would include outdoor activity every day, myopia control contact lenses and spectacles.’
‘The first thing to emphasise to any parent, and their child, with respect to myopic progression, is that there is no, one, proven, definitive, treatment, or intervention, that will retard or stop myopia progression. A condensed hand-out should be given for considered, home reflection and discussion; one based on the CPD article in Optician by Peter Black and Tina Arbon Black gives a good overview of myopic progression, the risks, and the various approaches being advanced to address it. Thereafter, the options are easier to narrow down to what is readily available, readily acceptable and readily affordable.’
Pros and Cons of Orthokeratology
One discussion summarised the pros of orthokeratology as follows: ‘Efficacy from one meta-analysis showed the change in axial length in the orthokeratology lens group was 0.27mm, equating to approximately 45% reduction in myopic progression. Also, the child has the immediate benefit of not having to wear spectacles with the freedom that can offer to some children and the effect it can have on the confidence of others, and, the long-term potential benefit of reducing their myopic progression.’
Another summarised the pros and cons as follows:
Pros:
- The use of orthokeratology may correct up to -4.00DS of myopia, but may regress once wear stopped
- Myopia progression may be slowed by up to 50%, thus reducing the risk of future medical issues
- Orthokeratology reduces problems from dry eye disease with daytime contact lens use
Cons:
- User compliance is really important to avoid corneal and eye health issues, particularly with this young patient
- Initial fitting takes up more patient chair time for the first three to six months
- Orthokeratology will not cure myopia, offering correction for just one day and a slowing of progression’
Another response picked up on the issues of chair time and motivation. ‘Motivation was always a large factor in successful RGP wear, necessary to overcome the initial discomfort experienced by most potential wears to this modality of refractive correction; this has an implication for compliance. As with occlusion therapy, ‘parent’ conviction and dedication to the regime has to be absolute for any sort of potential success. Orthokeratology demands more chair-time, and therefore more ‘parent time’ to bring children for aftercare visits, which can be time specific, and therefore more demanding to comply with. There is an increased risk of infection over spectacle wear, as is the case with any contact lens wear. There can also be the frustration of blurred vision as a result of poor compliance or the need to cease wearing lenses for a period of time due to illness, or such, for which the child might not have suitable spectacles to wear.’
Some of you already have specific approaches to myopia management and, therefore, the implication of the response was that your patient base was managed appropriately via alternative methods and approaches.
An example of this is as follows: ‘Our practice has, for some time, been prescribing the Stellist spectacle lens for myopia management. Unfortunately, we are based in a deprived area, so not many parents can afford to spend money on these lenses or any other types of treatment. When appropriate we explain the use of contact lenses as an alternative to specs, particularly if the child is sporty.
‘Rather than use orthokeratology, we tend to opt for an EDOF lens like Natural View and have experimented using it off label as extended wear. This gives the child myopia control 24/7 and only requires assisted or unassisted insertion and removal once a week. Ensuring the child has correctly fitting goggles is paramount if they are swimmers. Also, this becomes a far more affordable way for the parents to manage the threat of progressive myopia.’
Instrumentation
While answers varied, most agreed upon the need for a topographer.
‘In addition to the normal instrumentation for routine contact lens practice, a corneal topographer, in particular, and specifically, in relation to orthokeratology for myopic control, an optical biometer; the latter to establish the success or otherwise of orthokeratology intervention.’
‘Although our practice does possess a Medmont Meridian corneal topographer, which is essential for orthokeratology, we mainly use it to get K readings before any contact lens fit, and obviously it is invaluable when dealing with corneal ectasia.’
‘Equipment we felt we would need would include corneal topography, keratometry, a good slit lamp and OCT with axial measurement.’
Retallic comments
Neil Retallic adds: ‘As ECPs we have a duty to provide advice and recommendations tailored to the patient’s individual needs. Orthokeratology has rightly earnt a place as a myopia management offering, with proven efficiency for reducing axial elongation and providing the benefits of being eyewear free during the daytime. However, we should be careful with our communications to not over-promise on potential outcomes and should consider our record keeping and utilising a range of resources to enhance understanding.
‘Orthokeratology may be of particular interest to those parents who prefer to have more oversight and be on hand to provide support, given lens wear is when at home and/or where lifestyle is best matched to this option, for example avid swimmers. Of importance is to balance the low risk but high impact of possible complications such as microbial keratitis to the benefits of myopia management.
‘To simplify the lens selection and fitting process software or manufacturer’s support can be utilised. In addition to the usual practice equipment investment in a corneal topographer and optical biometer for axial length measurements, along with educational materials and consent forms would be best practice. Orthokeratology is an exciting, rewarding and evolving field and studies are showing enhancements to quality of life and enhanced patient satisfaction.’
- Neil Retallic is President of the BCLA.