Clinical Scorecard: Sagittal Height Considerations in Soft Lens Fitting

At a Glance

Key Highlights

• Keratometry covers only the central 3 mm of the cornea, while sagittal depth depends on diameter; using K readings alone to select soft lens base curve may oversimplify fitting.
• Measured contact lens sagittal heights differed substantially among lenses with the same labeled base curve, including across manufacturers.
• In a study of 30 subjects fitted with eight daily disposable lenses, objective and subjective assessments found satisfactory fit with lens sagittal height 120–280 µm deeper than ocular sagittal height; the authors state this may improve comfort.
• A study of 25 people with contact lens-related corneal infiltrative events or microbial keratitis found flatter ocular sagittal heights than in a control group of more than 18,000 contact lens wearers; the authors hypothesized a possible association with excessive lens steepness.

Guideline-Based Recommendations

Diagnosis

Management

Monitoring & Follow-up

Risks

Patient & Prescribing Data

The cited fitting study included 30 subjects; the adverse-event study included 25 participants diagnosed with a contact lens-related corneal infiltrative event or microbial keratitis and compared them with a control group of more than 18,000 contact lens wearers.

The article reports no medication treatment data. It describes lens fitting, with one study finding satisfactory fit for a lens sagittal height 120–280 µm deeper than ocular sagittal height.

Clinical Best Practices

• The article notes that central corneal curvature alone does not fully characterize soft lens fit and that trial fitting is still used.
• The article describes lens diameter and design as relevant to sagittal height.
• The article reports that lenses with the same labeled base curve can have substantially different sagittal heights.
• The article reports that switching between spherical and toric designs, including within a manufacturer, may substantially change sagittal height.
• The reported δ-sag range is a finding from a study of 30 subjects, not a universal fitting threshold.

Related Resources & Content

• Young et al. Corneal topography and soft contact lens fit (2010)
• van der Worp et al. Variation in sag values in daily disposable, reusable and toric soft contact lenses (2021)
• Cruz-Crespo et al. Changing the paradigm of soft contact lens fitting: A sagittal height-based approach (2025)
• Waghmare and Jeria. A review of contact lens-related risk factors and complications (2022)
• Ozkan et al. Risk factors for corneal inflammatory and mechanical events with extended wear silicone hydrogel contact lenses (2010)
• Andrew et al. The relationship between soft contact lens adverse events and corneal sagittal depth (2025)