Addressing Higher Order Aberrations to Enhance Patient Vision with Scleral Lenses

Overview

Higher order aberrations (HOAs) can significantly disrupt vision in patients with corneal irregularities such as keratoconus. Advances in scleral lens technology now allow for customized HOA correction, improving visual acuity beyond traditional correction methods.

Background

Higher order aberrations are subtle visual imperfections that often have minimal impact but can be significant in patients with corneal irregularities or prior refractive surgery. Historically, correction was limited to achieving functional vision levels, often between 20/25 and 20/40. Scleral lenses provide a stable optical surface that enables precise correction of HOAs, similar to custom LASIK. Common disruptive HOAs include vertical and horizontal coma, spherical aberrations, trefoil, and secondary astigmatism.

Data Highlights

Figure 1 illustrates significant vertical coma over a scleral lens in a keratoconus patient, highlighting an ideal candidate for HOA-correcting lenses. Visual acuity improvements from 20/100 to 20/30 with GP lenses were once considered a success, but HOA correction via scleral lenses aims to surpass 20/20 vision.

Key Findings

• HOAs are often subclinical but can cause symptoms like ghosting, streaking, halos, and glare in affected patients.
• Patients with keratoconus almost invariably have HOAs that can benefit from correction.
• Stable, centered scleral lens fit with minimal movement and rotation is essential for effective HOA correction.
• HOA correction is applied to the front surface of a custom-fitted scleral lens using aberrometry data.
• Post-correction measurements allow for fine-tuning to optimize visual outcomes.
• HOA correction with scleral lenses can significantly improve quality of vision, offering life-changing benefits.

Clinical Implications

Clinicians should assess patients with corneal irregularities for symptomatic HOAs using aberrometry or retinoscopy. Achieving a stable scleral lens fit is critical before applying HOA correction. Educating patients about the potential for improved vision beyond standard correction can enhance treatment acceptance and outcomes.

Conclusion

Custom HOA correction via scleral lenses represents a significant advancement in managing corneal irregularities, enabling vision quality improvements beyond traditional methods. Recognizing and addressing HOAs can profoundly enhance patients' visual experience.

References

1. Jedlicka JJ, 2024 -- Addressing Higher Order Aberrations to Enhance Your Patients’ Lives