Avaliação objetiva computadorizada dos parâmetros normais de contração dos músculos faciais

Abstract

Di fferent methods used to evaluate the movements of the face have many degrees of subjectivity and reliability. The authors discuss the ease of using these methods in clinical practice or their accuracy in scientific research. Aim:To obtain the standard for normal facial muscles movements using an objective method -the Vicon system. Materials and Methods:Light reflective markers were placed at points of interest on the face of 12 normal subjects. The movements were captured by cameras that sent the images to a computer. The points' displacements were measured between rest and maximum muscle contraction; and we calculated the means and the standard deviations (SD) were calculated.Results: When smiling, the variation of the oral commissures was between 6.45 and 12.11 mm, mean of 9.28 mm and SD od 2.83; for lifting the eyebrow, it is between 6.0 and 13.08 mm, mean of 10.57 mm and SD of 2.51; for eyelids movement there was a variation of 6.89 and 11.29 mm, with a mean value of 9.09 mm and SD of 2.20; for the movement of wrinkling the forehead, the results showed a variation of 4.16 and 10.85 mm, with a mean value of 7.56 and SD of 3.29. Conclusion:The authors obtained normal patterns for facial muscle contraction. Braz J Otorhinolaryngol. 2012;78(2):41-51. ORIGINAL ARTICLE

Accuracy and Reliability of 3D Imaging for Facial Movement Evaluation: Validation of the VECTRA H1

“…Examples include the requirement of bulky and expensive equipment, 21,22 standardized lighting conditions, 23,24 physical facial markers, 22,25 or multiple cameras that require frequent calibration. [26][27][28][29] The VECTRA H1 is a handheld device that is relatively inexpensive and does not require special lighting conditions or physical facial markers to be placed on the subject. A potential drawback of the VECTRA H1 system, however, is the requirement of a three-image capture procedure which makes image distortion and measurement error more probable if the patient cannot remain still or if images are not taken precisely.…”

Three-Dimensional Quantification of Facial Morphology and Movements Using a Wearable Helmet

“…Few numerical data from the literature are truly comparable. Some show data in the frontal plane only [ 13 , 15 , 17 ] or for specific vector characteristics [ 14 ] or separately for each participant [ 17 , 27 ] or results after scaling each face to an average facial size [ 19 ]. Coulson et al present ROM results of main markers for zygomaticus, frontalis, canine, and OP tasks [ 10 ].…”

“…The objective to measure the facial motions resulted in the definition of 10 tasks, each of them focusing on a facial muscle activation reflecting facial nerve function. In the literature, the number of markers varies from a few dots distributed on anatomical points [ 15 , 17 , 26 , 27 ] to high number of dots (nd = 64 [ 35 ], nd = 109 [ 46 ]). We chose 25 markers (drawn dots)—seven central and 18 lateral—to cover all the areas observed in the clinic without excessively complicating the practical experimental protocol.…”

“…The first challenge is to select marker types and positions. Most previous studies used adhesive and reflective markers of different diameters (from 3 mm [ 15 , 19 ] up to 9 mm [ 17 ]). Tzou et al reported that low contrast and shadows of facial creases sometimes interfered with the tracking process [ 18 ].…”