Background: Studies aiming to objectively evaluate facial movements have focused on the technique of measurement, whereas the most pertinent measurements of basic facial movements have not been well characterized.
Objective: To determine the best normal measures of 5 basic facial movements in healthy patients.
Methods: In 5 healthy subjects, 11 facial landmarks were placed on the face, and 5 movements (forehead lift, eye closure, nose wrinkling, lip puckering, and smiling) with maximal contraction force were requested. Each subject repeated each movement 3 times, and the entire session was repeated on 4 different days. No specific immobilization of the head was performed. The session was filmed with a digital camera, and the frames with maximal movement were selected. Measurements were performed with Osiris public domain image analysis software. For each measure, the change from rest was computed. Intersubject and intrasubject variability were determined by a multivariate analysis of variance.
Results: In all movements, surface changes (mean +/- SD) were higher than distance changes. For forehead lifting and eye closure, the best measure was the eye surface changes of 13% +/- 5% and -32% +/- 9%, respectively. For nasal wrinkling, lip puckering, and smiling, the best measures were the paranasal area (change, -28% +/- 9%), upper lip area (change, -23% +/- 8%), and mouth area (change, 63% +/- 21%), respectively. Most distance changes were below 10%. Same-day repeatability variation was below 15%, and day-to-day repeatability variation was below 7%. In healthy subjects, more than 80% of the total variation was accounted for by the intersubject variability.
Conclusions: Videomimicography is a simple and objective linear measurement system based on facial surface changes. The measures exhibit good reliability.