Reliability of grading lissamine green conjunctival staining

Area of Science:

• Ophthalmology
• Optometry
• Medical Imaging

Background:

• Conjunctival staining is crucial for assessing ocular surface health in contact lens wearers.
• Lissamine green is a vital dye used to evaluate conjunctival damage.
• Standardized grading scales are essential for reliable assessment of staining severity.

Purpose of the Study:

• To evaluate the inter-observer and intra-observer reliability of the Oxford lissamine green grading scale.
• To determine the consistency of lissamine green grading in clinical practice.

Main Methods:

• 288 contact lens wearers underwent lissamine green instillation and digital slit-lamp imaging.
• Nasal and temporal images were graded by two masked observers using the Oxford scale on separate occasions.
• Kappa statistics were employed to assess within- and between-grader reliability, stratified by demographics and disease severity.

Main Results:

• Substantial within-grader reliability was observed for both nasal (kappa=0.69) and temporal (kappa=0.73) images.
• Moderate between-grader reliability was found for nasal (kappa=0.51) and temporal (kappa=0.51) images.
• Disease severity, particularly significant staining, may reduce grading reliability.

Conclusions:

• The lissamine green grading scale demonstrates substantial to moderate reliability for conjunctival staining assessment.
• Clinicians and researchers should consider the potential impact of severe staining on grading consistency.
• Further validation may be needed for studies with high prevalence of significant conjunctival staining.