Global Consensus on Keratoconus and Ectatic Diseases - Edition 2

The Second Global Consensus on Keratoconus and Ectatic Diseases provides updated, evidence-based clinical guidelines for the diagnosis and management of corneal ectatic conditions 1. 

Published following the first consensus from 2015, this edition utilised a modified Delphi methodology to gather input from over 120 experts representing 12 international societies across six continents 12. 

It moves beyond simple topography, emphasising a multimodal diagnostic approach that integrates tomography and epithelial thickness mapping 3. 

The document includes new recommendations regarding pediatric treatment, disease progression criteria, and re-treatment strategies to standardize global standards of care 12.

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 The Second Global Consensus on Keratoconus and Ectatic Diseases (2026) 

Overview

The Global Consensus on Keratoconus and Ectatic Diseases – Edition 2 updates the 2015 international guidelines, incorporating advances in corneal imaging, biomechanics, cross-linking, and surgical management. The recommendations are based on expert consensus from ophthalmologists worldwide.

1. Diagnosis

• Keratoconus should be diagnosed using multiple clinical and imaging parameters, not a single measurement.
• Corneal tomography is the primary imaging modality.
• Corneal biomechanics and epithelial thickness mapping provide additional diagnostic value, particularly for detecting early or subclinical disease.
• Careful screening is essential before refractive surgery to identify eyes at risk of ectasia.

2. Disease Progression

• Progression should not be determined by Kmax alone.
• Assessment should include changes in:
• Anterior corneal curvature
• Posterior corneal curvature
• Corneal thickness (pachymetry)
• Tomographic indices
• Refraction
• Visual acuity
• Multiple consistent changes are preferred before confirming progression.

3. Classification

• Older grading systems, such as Amsler–Krumeich, have important limitations.
• Modern tomography-based classifications, particularly the Belin ABCD system, are recommended because they better reflect disease severity.

4. Corneal Cross-Linking (CXL)

• CXL remains the only treatment proven to halt keratoconus progression.
• Early treatment is recommended for patients with documented progression.
• Children and adolescents should be monitored closely because they often experience faster progression.
• Repeat CXL may be considered if progression recurs after initial treatment.

5. Visual Rehabilitation

Management should progress from the least invasive to more advanced options:

• Spectacles
• Soft toric contact lenses
• Specialty soft lenses
• Rigid gas-permeable lenses
• Hybrid lenses
• Scleral lenses
• Intracorneal ring segments (selected patients)
• Corneal transplantation when necessary

6. Corneal Transplantation

• Deep Anterior Lamellar Keratoplasty (DALK) is preferred whenever feasible because it preserves the patient's corneal endothelium and reduces the risk of graft rejection.
• Penetrating keratoplasty remains appropriate when DALK is not possible.

7. Cataract and Refractive Surgery

The consensus provides updated recommendations for:

• Cataract surgery planning
• Intraocular lens (IOL) power calculations
• Screening for refractive surgery candidates to reduce the risk of postoperative ectasia

8. Eye Rubbing and Allergy

• Eye rubbing is recognised as a major modifiable risk factor for keratoconus progression.
• Allergic eye disease and ocular surface inflammation should be identified and treated to help reduce rubbing and disease progression.

Key Take-Home Messages

• Use multimodal imaging rather than relying on a single test.
• Do not use Kmax alone to diagnose or monitor progression.
• Corneal tomography is central to diagnosis and follow-up.
• Cross-linking is the standard treatment to stop progression and should be performed early in appropriate patients.
• DALK is the preferred transplant technique** when transplantation is required.
• Preventing eye rubbing and managing ocular allergy are essential components of care.

Overall, Edition 2 emphasises earlier diagnosis, multimodal assessment, individualised management, and timely intervention, reflecting the substantial advances in keratoconus care since the original 2015 consensus.