Karen R. Hoffman, OD, is a corneal specialist who is seeing an increasing number of patients with irregular astigmatism and complex corneal conditions seeking clearer vision and improved comfort. In this case series, she explores how customizable toric peripheral curves in scleral lenses—specifically using the Zenlens (Bausch + Lomb)—significantly improve fit, vision, and wearability in patients with challenging ocular anatomy.
By leveraging the advanced customization of scleral lenses in 3 distinct zones (optical zone, vaulting chamber, and peripheral haptic), optometrists can achieve precise alignment even in asymmetric scleral shapes. Here are three illustrative cases that highlight the power and flexibility of toric and quadrant-specific peripheral adjustments.
Case 1: Salzmann nodular degeneration
Key takeaways for clinical practice
- Customizable APS zones allow clinicians to accommodate highly irregular scleral and corneal geometries.
- Distributing toricity into mid-peripheral zones improves centration and limbal clearance.
- Microvaults and quadrant-specific haptics can address peripheral elevations and scarring without compromising fit.
- Efficient fitting process: All cases achieved success within 1–3 revisions.
- Excellent visual and comfort outcomes: Each patient achieved 20/20 vision with high comfort and extended wear time (8–14 hours).
Patient: 51-year-old female
Condition: Left eye with Salzmann nodular degeneration and irregular astigmatism
Pre-Lens VA: 20/80 in spectacles
Findings: 4.00 D corneal and 5.00 D refractive astigmatism
Lens Design:
- APS (Advanced Peripheral System): Flat Meridian = Steep 1; Steep Meridian = Steep 5
- 4 steps of toricity in the peripheral haptic
Outcome:
- 2 revisions
- Final VA: 20/20
- 12 hours of comfortable wear
Case 2: Post-globe rupture scarring
Patient: 38-year-old male
Condition: Left eye with irregular astigmatism and corneal/scleral scarring post-globe rupture
Pre-Lens VA: 20/80 in spectacles
Findings: 2.00 D corneal and 2.00 D refractive astigmatism
Lens Design:
- APS: Flat 2, Steep 2 (3 steps of toricity)
- Additional vault near lens edge to accommodate peripheral scarring
Outcome:
- 3 revisions
- Final VA: 20/20
- 14 hours of wear with high satisfaction
Case 3: Keratoconus suspect with high astigmatism
Patient: 38-year-old female
Condition: Bilateral high astigmatism, suspected keratoconus
Pre-Lens VA: 20/20 in spectacles, but poor comfort and satisfaction
Findings:
- OD: 3.50 D corneal / 3.25 D refractive astigmatism
- OS: 4.75 D corneal / 3.50 D refractive astigmatism
Lens Design:
- OD APS: Flat 3 / Steep 11 (8 steps of toricity)
- OS: Toricity distributed between APS and mid-peripheral vaulting chamber
- Added microvault for peripheral elevation in OS
Outcome:
- 1 revision (OD), 2 revisions (OS)
- Final VA: 20/20 OU
- 8 hours daily wear, high patient satisfaction
Conclusion
These cases demonstrate that fitting scleral lenses for irregular corneas and scleras doesn't have to be overly complex. With tools like Zenlens and an understanding of toric and quadrant-specific customization, optometrists can reliably deliver excellent visual and comfort outcomes — even for the most complex patients.
