Objective measurement of normal facial movement with video microscaling.

This study examines variability in facial movements in normal subjects using a new objective method of measuring facial movement, video microscaling. Video microscaling superimposes a computer-generated measuring scale over a video recorded image of facial movements. Distances moved are determined digitally. Eleven subjects were tested raising the eyebrows and smiling five times on two separate days. Test-retest, day-to-day, side-to-side, and intersubject variability were evaluated. Average variability was relatively low; however, some normal subjects exhibited considerable variability, particularly from day-to-day and from side-to-side. Because of this, a facial nerve grading system based solely on objective measurements of facial movements may be invalid. Video microscaling is a promising research technique.