Blepharokymographic analysis of eyelid motion in Bell's palsy

OBJECTIVE: To present characteristics of eyelid motion measured by blepharokymography in Bell's palsy patients and to discuss possible roles and limitations of blepharokymography. STUDY DESIGN: Retrospective analysis. METHODS: The study included 72 patients with Bell's palsy who presented to the Department of Otolaryngology at Asan Medical Center, Seoul, Korea, between April 2002 and March 2005, and who underwent both electroneuronography and blepharokymography. Parameters of eyelid motion were measured using revised blepharokymography. Correlations between blepharokymography and electroneuronography or House-Brackmann grade were examined by Spearman rank correlation and Kendall's tau-b correlation, respectively. RESULTS: Compared with the normal side, all parameters of eyelid motion except opening time were decreased on the palsy side, with peak closing velocity showing the greatest difference (40.2%). On average, paralytic eyelids moved down 6.5 mm in 277 ms with a peak velocity of 55.4 mm/s, whereas normal eyelids moved down 9.7 mm in 214 ms, with a peak velocity of 142.6 mm/s. Subtle paralytic eyelid motion or "lid lag" could be objectively documented by blepharokymography to have longer and gentler downward slopes in displacement curves. Most blepharokymographic parameters correlated with ocular electroneuronography and House-Brackmann grade. CONCLUSIONS: Slow or incomplete closure of paralytic eyelids can be graphically and numerically analyzed by blepharokymography. Blepharokymography may be useful for evaluating status, predicting prognosis, and assessing effects of rehabilitative procedures, including gold weight implants in patients with facial palsy.