IN 1961, it was proposed that it should, in principle, be possible to manufacture contact lenses (CLs) that can compensate for the wave aberrations of the eye (Smirnov, 1961).

By the early 2000s, that vision had become a real possibility, thanks to technological advancements in adaptive optics and wavefront technologies (Eisenberg, 2005; Kollbaum and Bradley, 2007 Nov.; Norman, 2003). Novel Hartmann-Shack wavefront aberrometers had become available, allowing the measurement of ocular aberrations in milliseconds (Kollbaum and Bradley, 2007 Dec.), and CL manufacturers had started developing new lens designs specifically aimed at minimizing higher-order aberrations (HOAs) (Eisenberg, 2005; Norman, 2003; Kollbaum and Bradley, 2007 Dec.; Edwards, 2003).

Fast forward to 2009, when a number of mass-produced contact lenses for aberration control were available. Individually designed lenses remained rather uncommon and were very expensive (Lindskoog Pettersson et al, 2008). Since then, literature on the fitting of customized lenses for aberration control has almost exclusively reported on the advantages of and success with customized contact lenses for the correction of irregular or keratoconic corneas (Jinabhai et al, 2014; Suzaki et al, 2021), with little to no mention of “super vision” correction for the mass market. To understand why, we need to consider three key factors.

First, consider the impact of ocular aberrations (OAs) on a patient’s vision. OAs are optical imperfections of the eye that may negatively impact the quality of a patient’s vision (Porter et al, 2001). Every patient has some level of OAs (Richdale et al, 2021), with lower-order aberrations (second-order or lower) comprising refractive error and accounting for greater than 90% of OAs in the typical patient (Porter et al, 2001).

HOAs (third-order and higher) thus make up fewer than 10% of the total aberrations, with a magnitude of roughly 0.25D (Thibos et al, 2002). Spherical aberration is the only HOA (fourth-order) that has a population mean that is significantly different from zero (equivalent to 0.08D to 0.16D) and may negatively impact a patient’s quality of vision, particularly as it increases with age (Porter et al, 2001; Thibos et al, 2002; Kingston and Cox, 2013; Dave, 2008).

Today, many CL manufacturers use aspheric lens surfaces in an attempt to minimize spherical aberrations based on population-based averages of spherical aberration for normal eyes (Dave, 2008; CooperVision, 2023; Bausch + Lomb, 2023; Alcon, 2023).

Second, it is quite possible that the individualized contact lenses didn’t work on the eye as intended and inadvertently caused more HOAs to occur (Norman, 2003; López-Gil et al, 2009; Thibos et al, 2003). It is well known that a patient’s aberrations may change quickly due to physiological or tear film changes, meaning that a lens that perfectly corrected aberrations at one time may not do so at another (Thibos et al, 2002; Dave, 2008; López-Gil et al, 2009; Thibos et al, 2003). These lenses are also required to be rotationally and translationally stable, although lid forces and changing head positions make this unrealistic (López-Gil et al, 2009; Thibos et al, 2003).

Finally, convincing a patient to pay more for an individualized contact lens may be difficult. Unless vision is significantly impacted by aberrations, most lens wearers are happy with the vision that they can achieve with standard corrections, even with uncorrected HOAs.

The challenges of unwanted lens rotation and translation, the typically small number of HOAs in normal eyes, and the higher cost of individually designed lenses have likely limited the path to achieving “super vision” for everyone. For aberration control lenses to become a clinical reality, these obstacles will have to be overcome to provide a tangible benefit to wearers and will be a challenge to researchers and the industry. CLS

References

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