Measurement of facial movement with computer software.
OBJECTIVE
To adapt desktop computer software to objectively grade facial movement.


METHODS
The criteria of the facial nerve grading system by House and Brackmann, the current "gold standard," are prone to ambiguous interpretation. Proposed objective grading systems compare the movement of points on each side of the face or use subtraction and thresholding of digitized images of the face to yield images that represent moving areas of the face. The movement of a point on the face and the area of motion determined by digital subtraction were compared during an increasing smile in healthy subjects. The Nottingham system (calculated using measurement of the movement of 4 points on the face) using desktop computer software (Adobe Photoshop 3.0, Adobe Systems Inc, Mountain View, Calif) to measure movement of the points was compared with the system by House and Brackmann. The computer software was used to subtract digitized images and derive a facial movement score, which was compared with the scores of the systems by Nottingham and House and Brackmann.


METHODS
Academic otologic practice.


METHODS
Nine patients with varying degrees of facial nerve disability and 7 individuals with normal facial nerve function.


RESULTS
The movement of the oral commissure compared with the apparent area of movement of the face determined by digital subtraction had high intersubject variability. In patients with facial weakness, the Nottingham score had a correlation coefficient of -0.97 compared with the House and Brackmann grade, and the digital subtraction score had a correlation coefficient of -0.62 (paired Student t test).


CONCLUSIONS
The desktop computer software can be used to calculate the Nottingham score. Digital subtraction as a measure of facial function warrants further study.
Sargent
E W
EW
Department of Otolaryngology-Head and Neck Surgery, St Louis University School of Medicine, MO 63110-0250, USA. sargente@slu.edu
Fadhli
O A
OA
Cohen
R S
RS
D016251:CD-ROM; D003198:Computer Simulation; D005145:Face / Q000502:physiology*; D005149:Facial Expression; D005152:Facial Muscles / Q000502:physiology; D005158:Facial Paralysis / Q000503:physiopathology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D009068:Movement; D010781:Photography; D012984:Software