title: The clinical application of three-dimensional motion capture (4D): a novel approach to quantify the dynamics of facial animations.
abstract: The aim of this pilot study was to evaluate the feasibility of measuring the change in magnitude, speed, and motion similarity of facial animations in head and neck oncology patients, before and after lip split mandibulotomy. Seven subjects (four males, three females) aged 42-80 years were recruited. The subjects were asked to perform four facial animations (maximal smile, lip purse, cheek puff, and grimace) from rest to maximal position. The animations were captured using a Di4D motion capture system, which recorded 60 frames/s. Nine facial soft tissue landmarks were manually digitized on the first frame of the three-dimensional image of each animation by the same operator and were tracked automatically for the sequential frames. The intra-operator digitization error was within 0.4mm. Lip purse and maximal smile animations showed the least amount of change in magnitude (0.2mm) following surgery; speed difference was least for smile animation (-0.1mm/s). Motion similarity was found to be highest for lip purse animation (0.78). This pilot study confirmed that surgery did influence the dynamics of facial animations, and the Di4D capture system can be regarded as a feasible objective tool for assessing the impact of surgical interventions on facial soft tissue movements.
authors.affiliation: Oral & Maxillofacial Surgery, Faculty of Medicine, MVLS College, Glasgow University Dental Hospital and School, Glasgow, UK.
authors.forename: S
authors.initials: S
authors.lastname: Shujaat
authors.affiliation: Oral & Maxillofacial Surgery, Faculty of Medicine, MVLS College, Glasgow University Dental Hospital and School, Glasgow, UK.
authors.forename: B S
authors.initials: BS
authors.lastname: Khambay
authors.affiliation: Oral & Maxillofacial Surgery, Faculty of Medicine, MVLS College, Glasgow University Dental Hospital and School, Glasgow, UK.
authors.forename: X
authors.initials: X
authors.lastname: Ju
authors.affiliation: Regional Maxillofacial Unit, Southern General Hospital, Glasgow, UK.
authors.forename: J C
authors.initials: JC
authors.lastname: Devine
authors.affiliation: Regional Maxillofacial Unit, Southern General Hospital, Glasgow, UK.
authors.forename: J D
authors.initials: JD
authors.lastname: McMahon
authors.affiliation: Regional Maxillofacial Unit, Southern General Hospital, Glasgow, UK.
authors.forename: C
authors.initials: C
authors.lastname: Wales
authors.affiliation: Oral & Maxillofacial Surgery, Faculty of Medicine, MVLS College, Glasgow University Dental Hospital and School, Glasgow, UK. Electronic address: ashraf.ayoub@glasgow.ac.uk.
authors.forename: A F
authors.initials: AF
authors.lastname: Ayoub
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005149:Facial Expression; D005240:Feasibility Studies; D005260:Female; D006258:Head and Neck Neoplasms / Q000503:physiopathology* / Q000601:surgery; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010780:Photogrammetry / Q000295:instrumentation*; D010865:Pilot Projects; D011446:Prospective Studies
keywords: 2D imaging; 3D imaging; 4D imaging; access surgery; animations; face; lip split; lips; oropharyngeal cancer