Managing Diurnal Refractive Fluctuations Post-Radial Keratotomy with Scleral Lenses

Overview

This case report describes a 64-year-old post-radial keratotomy (RK) patient experiencing significant diurnal hyperopic refractive fluctuations successfully managed with customized scleral lenses. The lenses provided stable vision throughout the day despite the patient's unique hyperopic shift, contrasting the more common myopic fluctuations seen in RK patients.

Background

Radial keratotomy, once a popular surgical method for myopia correction in the early 1990s, involved multiple deep corneal incisions to flatten the cornea. Although largely replaced by laser vision correction, many post-RK patients experience complications such as irregular astigmatism, corneal ectasia, and diurnal refractive fluctuations, typically shifting toward myopia. Approximately 60% of these patients report vision fluctuations throughout the day. Previous studies have documented refractive changes averaging 1.48 diopters more hyperopic in the morning compared to later in the day. Management options include contact lenses and emerging treatments like corneal cross-linking.

Data Highlights

Key Findings

• The patient exhibited significant diurnal hyperopic refractive fluctuations, with afternoon refractions more hyperopic than morning measurements.
• Customized scleral lenses with specific parameters (diameter, base curve, toric landing zone) provided stable, 20/20 vision without diurnal fluctuations.
• The patient’s corneas showed 8 radial incisions per eye without additional scarring or neovascularization.
• Unlike typical RK patients who shift toward myopia, this patient’s refractive shift was hyperopic.
• Scleral lenses not only corrected irregular astigmatism but also stabilized diurnal refractive changes in this case.
• Alternative management strategies include high-Dk soft lenses and corneal cross-linking, though these may induce hyperopic shifts or have limited data.

Clinical Implications

Clinicians should consider customized scleral lenses for post-RK patients experiencing diurnal refractive fluctuations, especially when irregular astigmatism and oblate corneal surfaces complicate vision correction. Scleral lenses can provide stable vision throughout the day and mitigate fluctuations, improving patient quality of life. Awareness of the potential for hyperopic shifts in some patients is important when planning management.

Conclusion

This case highlights the successful use of customized scleral lenses to manage significant diurnal hyperopic refractive fluctuations in a post-RK patient, demonstrating an effective approach to stabilizing vision in this challenging population.

References

1. National Eye Institute 1994 -- Ten-year results on radial keratotomy released
2. Waring et al 1987 -- Three-year results of the Prospective Evaluation of Radial Keratotomy (PERK) Study
3. Mader et al 1995 -- Refractive changes at extreme altitude after radial keratotomy
4. Chang et al 2025 -- Radial keratotomy: complications management
5. McRae et al 1989 -- Diurnal variation in vision after radial keratotomy
6. Inoue et al 2000 -- Minimizing radial-keratotomy-induced diurnal variation in vision using contact lenses
7. Elbaz et al 2014 -- Collagen crosslinking after radial keratotomy