Grading static versus dynamic images of contact lens complications.

BACKGROUND

This study was conducted to investigate grading performance when estimating the severity of static versus dynamic images of contact lens-related ocular pathology.

METHODS

Thirty-eight subjects used the Efron Grading Scales for Contact Lens Complications to grade the severity of ocular pathological changes depicted in static and dynamic (movie clip) computer-displayed images of each of the following contact lens complications: bulbar conjunctival redness, limbal redness, papillary conjunctivitis, corneal staining, corneal infiltrates and meibomian gland dysfunction. The viewing of static and dynamic images was separated by seven weeks.

RESULTS

Grades assigned to dynamic images were 0.6 and 0.7 grading scale units higher than those assigned to static images for limbal redness and papillary conjunctivitis, respectively (p < 0.0001 for both). No difference was observed for the other four complications. There was an apparent trend for grading variability to be reduced (that is, observers grading in closer agreement) when grading dynamic versus static images.

CONCLUSIONS

Absolute grades based on an assessment of signs of pathology represented in static images may, in some instances, underestimate the true severity of the condition.