Automated facial image analysis: detecting improvement in abnormal facial movement after treatment with botulinum toxin A.

Abstract

The purpose of this study was to evaluate the ability of Automated Facial Image Analysis (AFA) to detect changes in facial motion after Botox injections in patients with facial nerve disorders accompanied by abnormal muscle activity. Eight subjects received Botox for oral to ocular synkinesis (n = 6), ocular to oral synkinesis (n = 1), and/or depressor anguli oris overactivity (n = 3). Subjects were video-recorded during 2 directed facial action tasks before and after Botox treatment. AFA measurement and Facial Grading System (FGS) scores were used to evaluate the effects of Botox. After Botox, AFA detected a decrease in abnormal movements of the eyelids in all patients with oral to ocular synkinesis, a decrease in oral commissure movement for the patients with ocular to oral synkinesis, and an increase in oral commissure movement in all patients with depressor overactivity. The FGS scores failed to demonstrate any change in facial movement for the case of ocular to oral synkinesis and for 2 cases of depressor overactivity. AFA enables recognition of subtle changes in facial movement that may not be adequately measured by observer based ratings of facial function.