Sunnybrook and House-Brackmann systems in 5397 facial gradings

Abstract

Objectives: To study the correlation between Sunnybrook and House-Brackmann facial grading systems at different time points during the course of peripheral facial palsy.

Study design: Prospective multicenter trial.

Setting: Seventeen otorhinolaryngological centers.

Subjects and methods: Data are part of the Scandinavian Bell's palsy study. The facial function of 1920 patients with peripheral facial palsy was assessed 5397 times with both Sunnybrook and House-Brackmann (H-B) facial grading systems. Grading was done at initial visit, at days 11 to 17 of palsy onset, and at 1 month, 2 months, 3 months, 6 months, and 12 months. Statistical evaluation was by Spearman correlation coefficient and box plot analysis.

Results: Spearman correlation coefficient varied from -0.81 to -0.96, with the weakest correlation found at initial visit. Box plot analysis for all assessments revealed that Sunnybrook scores were widely spread over different H-B grades. With 50% of the results closest to the median, Sunnybrook composite scores varied in H-B grades as follows: H-B I, 100; H-B II, 71 to 90; H-B III, 43 to 62; H-B IV, 26 to 43; H-B V, 13 to 25; and H-B VI, 5 to 14.

Conclusion: Gradings correlated better in follow-up assessments than at initial visit. As shown by the wide overlap of the grading results, subjective grading systems are only approximate. However, a conversion table for Sunnybrook and H-B gradings was obtained and is included in the article. It can be used for further development of facial grading systems.