Limited Utility of Keratic Precipitate Morphology as an Indicator of Underlying Diagnosis in Ocular Inflammation

Abstract

ABSTRACT Objectives We aimed to establish the degree of consensus among clinicians on descriptors of KP morphology. Methods A web-based exercise in which respondents associated KP descriptors, as identified through a scoping review of the published literature, to images from different disorders. Inter-observer agreement was assessed using the Krippendorff kappa alpha metric. Results Of the 76 descriptive terms identified by the scoping review, the most used included “mutton-fat” (n = 93 articles, 36%), “fine/dust” (n = 76, 29%), “stellate” (n = 40, 15%), “large” (n = 33, 12%), and “medium” (n = 33, 12%). The survey of specialists (n = 26) identified inter-observer agreement for these descriptors to be poor (“stellate,” kappa: 0.15, 95% confidence interval 0.13–0.17), limited (“medium”: 0.27, 95% CI 0.25–0.29; “dust/fine”: 0.36, 95% CI 0.34–0.37), or moderate (“mutton fat”: 0.40, 95% CI 0.36–0.43; “large”: 0.43, 95% CI 0.39–0.46). Conclusion The clinical utility of KP morphology as an indicator of disease classification is limited by low inter-observer agreement.