This study examines variability in facial movements in normal subjects
using a new objective method of measuring facial movement, video micr
oscaling. Video microscaling superimposes a computer-generated measuri
ng scale over a video recorded image of facial movements. Distances mo
ved 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. Av
erage variability was relatively low; however, some normal subjects ex
hibited considerable variability, particularly from day-to-day and fro
m side-to-side. Because of this, a facial nerve grading system based s
olely on objective measurements of facial movements may be invalid. Vi
deo microscaling is a promising research technique.