It’s important for clinicians to keep in mind that many regular cornea patients also wish to achieve best visual function while remaining spectacle-free; however, dissatisfactions with frequent replacement soft contact lenses often lead to contact lens dropout. Despite the advancing strides that have been made in frequent replacement soft spherical and soft toric contact lenses, numerous studies have demonstrated that contact lens dropout ranges from 15 to over 20 percent.2-6
The reasons for contact lens dropout are likely multifactorial because no single risk factor has been found to conclusively predict such a negative outcome. Nonetheless, the incidence of contact lens dropout has been observed to significantly increase as one enters the fifth decade of life. It is easy to jump to the conclusion that emerging presbyopia may be the primary culprit limiting patient satisfaction at this stage of life; in actuality, vision and comfort have been reported as equal contributors for contact lens dropout after age 45.7
According to the Tear Film and Ocular Surface Society (TFOS), patients often begin experiencing physical awareness and/or visual disturbance. With increasing lens-related discomfort potentially exacerbated by extrinsic environmental factors, permanent discontinuation (or lens dropout) invariably becomes a reality for these patients (Figure 2A and 2B).8
Moving to scleral lenses
Given the optical advantage of corneal cylinder neutralization and therapeutic benefit of improved corneal surface hydration, scleral lenses can significantly improve the contact lens-wearing experiences for otherwise normal, healthy eyes—especially when these patients fail soft lenses or are considering dropping out of soft lenses altogether. Transitioning a patient from other contact lens modalities to scleral lenses is certainly attainable and may proactively prevent contact lens dropout.
Thus, a logical entry point to start considering scleral lens technology for a regular cornea patient can be when a patient wishes to remain in contact lenses but is dissatisfied with his current soft, soft toric, corneal GP, or hybrid contact lenses. Given the high prevalence rate in clinical utilization of soft contact lenses, the majority of patients reporting contact lens dissatisfaction who most clinicians will encounter are those who are currently wearing soft spherical or soft toric contact lenses.
Perhaps patients are finding their frequent replacement lenses are not as comfortable as desired, particularly at the end of the day, or maybe soft lenses do not provide the level of vision required throughout the entire wearing period.
Because soft toric lenses may become rotationally unstable with each blink, an astigmatic patient may complain of fluctuating vision throughout the day, even in the presence of a healthy lacrimal unit. In addition, similar visual challenges related to lens destabilization can occur when astigmatic patients assume a non-primary gaze position, especially during supero-nasal and infero-temporal excursions.9 Due to exceptional lens stability and crisp GP optics, scleral lenses are unmatched in their abilities to maintain clear and consistent vision all day long. This is particularly important for patients with high corneal astigmatism and/or those who participate in visually demanding athletic activities.