Clinical Scorecard: Orthokeratology Today: Topography Tells the Tale

At a Glance

Key Highlights

• Topography is the most informative metric for assessing orthokeratology lens fit and performance.
• Tangential maps are critical for evaluating treatment zone size, shape, and centration; axial maps assess power change and optical quality.
• Treatment zone decentration may not require correction and can enhance myopia control, but mechanical fit issues should be addressed first.

Guideline-Based Recommendations

Diagnosis

• Use corneal topography maps (axial, tangential, elevation) to assess lens fit and corneal changes.
• Evaluate treatment zone size relative to pupil diameter to optimize optical outcomes and myopia control.

Management

• Adjust sagittal height or peripheral curves based on decentration direction to improve lens centration.
• Consider increasing treatment zone size in teenage patients to reduce nighttime glare and flare.
• Prioritize correcting mechanical fit issues before making optical changes.

Monitoring & Follow-up

• Use difference maps at follow-up visits to assess treatment stability and progression.
• Monitor treatment zone centration and size relative to pupil size, especially under mesopic conditions.
• Observe corneal health and patient symptoms before deciding on intervention for decentration.

Risks

• Inferior decentration may indicate excessive sagittal height or tight fit; superior decentration may indicate insufficient sagittal height.
• Decentration can cause ghosting or flare, particularly in low light conditions.
• Small treatment zones may increase myopia control but could affect visual quality.

Patient & Prescribing Data

Myopic patients, especially children and teenagers with progressive myopia

Smaller treatment zones are associated with stronger myopia control effects in younger patients; treatment zone size may need adjustment with age to balance control and visual quality.

Clinical Best Practices

• Use tangential maps to evaluate lens fit and axial maps to assess power change and optical quality.
• Interpret difference maps to monitor corneal changes and treatment progression.
• Address mechanical fit issues before modifying optical parameters.
• Consider patient age and symptoms when deciding on treatment zone size adjustments.
• Not all treatment zone decentration requires correction if vision and corneal health are stable.

References

• Gong et al, 2024 - Efficacy of orthokeratology lens with the modified small treatment zone on myopia progression and visual quality
• Wang and Yang, 2019 - Influence of overnight orthokeratology lens treatment zone decentration on myopia progression
• Hiraoka et al, 2015 - Influence of ocular wavefront aberrations on axial length elongation in myopic children treated with overnight orthokeratology