Fitting GP lenses requires a dedication to precise data collection, collaboration with labs and consultants, and an ability to guide patients along a sometimes difficult journey of adaptation to lens wear. GP fitting becomes easier—and even enjoyable—once practitioners learn to avoid common mistakes that lead to prolonged fits and to frustration.
The first common mistake is using old or incorrect fitting data, which may include failing to update keratometry or topography prior to lens ordering or basing lens power on a rushed refraction. This can lead to the need for more lens remakes and patient follow-up visits than is often necessary. Careful data collection is critical to GP lens success, particularly when ordering empirically.
Additionally, it is common for practitioners to try to make too many changes too quickly. Judging lens fit after just a few minutes of wear can lead to erroneous assessments of fit and vision as well as to remakes that do more to confuse further improvements than to assist.
All new GP lens wearers require some time for adaptation, and excessive tearing or blinking can make it difficult to accurately assess a lens fit. Similarly, vision in GP multifocals can require significant neural adaptation, and it doesn’t help to rush to make changes in lens power before this has had a chance to occur.
If the fit of and vision with a new empirically fit GP lens is reasonably good (which it should be, assuming that data was collected carefully and accurately), then it is advisable to dispense the lens and plan to make adjustments at a follow-up visit after patients have worn the lens for at least a few days.
Other GP lens modalities benefit from patience as well. Orthokeratology treatment occurs at different rates in each patient, and patience is very often a virtue when waiting for topographies and vision to improve with this modality (Figure 1). If centration is good and refraction over the lens is as expected, then there is no rush to adjust fitting parameters, especially after less than a week of overnight wear.
The fit of a scleral lens can change with lens settling over time and also with variations in patient application techniques. Forceful lens application can cause practitioners to see haptic scleral compression and conjunctival prolapse that wouldn’t necessarily be there if the lenses were applied more gently. Letting patients adjust to scleral lens application through practice can often improve the fit appearance.
Lastly, though not a fitting mistake, it is easy to lose track of the financial end of GP lens fittings. Patients may inadvertently be dispensed lenses before paying for them. Additionally, insurance reimbursements may lag or aren’t received for various reasons, or remakes are not returned in time for warranty reimbursement.
Multiple mistakes might make GP lens fitting seem like it is not profitable enough to be worth the time and effort involved. However, if staff and practitioners are motivated to develop systems to avoid mistakes, GP lens fitting can be very rewarding, and happy and loyal patients will surely make the effort worthwhile. CLS