The House-Brackmann system and assessment of corneal risk in facial nerve palsy

Purpose The House-Brackmann (HB) facial nerve grading system is widely used by ENT/ head and neck surgeons, but is perhaps of less value to the ophtha lmologist. Our aim was to assess the value of the numeric portion of this s ystem in identifying those patients with facial nerve palsy who are at risk of conceal complications. We also sought to identify other factors that mi ght be predictive of such complications. Methods Forty-two patients (43 palsies) were studied prospectively. The HE grade was recorded together with measurements of levator function, upper li d closure, Bell's phenomenon, lagophthalmos, ectropion, lower lid retractio n and conceal sensation. Conjunctival injection and conceal staining were a lso graded. ROC (receiver operating characteristic) curves were used to ass ess the value of each parameter as a screening test for corneal complicatio ns. Results There was no cut-off of HE grade, levator function, Bell's phenomen on, ectropion or lower lid retraction that was sufficiently sensitive and s pecific to screen for conceal complications. However, on assessing lagophth almos and upper lid closure, cut-offs with more favourable sensitivities an d specificities were identified. Conclusions The numeric portion of the HE grading system is not a useful gu ide in identifying those patients with facial nerve palsy who are at risk o f conceal complications. Measurements of lagophthalmos and upper lid closur e, alone or in combination with other tests, may be of more value.