Quantified analysis of facial movement: A reference for clinical applications

Most techniques for evaluating unilateral impairments in facial movement yield subjective measurements. The objective of the present study was to define a reference dataset and develop a visualization tool for clinical assessments. In this prospective study, a motion capture system was used to quantify facial movements in 30 healthy adults and 2 patients. We analyzed the displacements of 105 reflective markers placed on the participant's face during five movements (M1-M5). For each marker, the primary endpoint was the maximum amplitude of displacement from the static position (M0) in an analysis of variance. The measurement precision was 0.1 mm. Significant displacements of markers were identified for M1-M5, and displacement patterns were defined. The patients and age-matched healthy participants were compared with regard to the amplitude of displacement. We created a new type of radar plot to visually represent the diagnosis and facilitate effective communication between medical professionals. In proof-of-concept experiments, we collected quantitative data on patients with facial palsy and created a patient-specific radar plot. Our new protocol for clinical facial motion capture ("quantified analysis of facial movement," QAFM) was accurate and should thus facilitate the long-term clinical follow-up of patients with facial palsy. To take account of the limitations affecting the comparison with the healthy side, we created a dataset of healthy facial movements; our method might therefore be applicable to other conditions in which movements on one or both sides of the face are impaired. The patient-specific radar plot enables clinicians to read and understand the results rapidly.

Anatomical study of the course of the inferior alveolar nerve in craniofacial microsomia using three-dimensional computed tomography: correlation with the Pruzansky classification

Dysmorphogenesis of the mandible complicates assessment of the course of the inferior alveolar nerve in patients with craniofacial microsomia. Our aim in the present study was to correlate the anatomical description of the course with the Pruzansky classification (which indicates the severity of hemifacial microsomia), in the mandibles of 22 affected patients using 3-dimensional computed tomography (CT). We measured the distance between fixed landmarks on the normal and the microsomic sides. The normal sides served as controls. In the group of five patients with type I disease, we found no significant differences between the unaffected and the microsomic side. In the nine patients with Pruzansky type II disease morphological views of the course showed a between-side difference in the length of the bony canal and the height of the mandibular ramus. In the five patients with Pruzansky type III disease, there was no bony canal. Three-dimensional CT analysis may be of value in plotting the course of the inferior alveolar nerve and assisting the surgeon in mandibular osteotomy or distraction osteogenesis.