3D digital surface imaging for quantification of facial development and asymmetry in juvenile idiopathic arthritis

3D digital surface imaging (digital stereophotogrammetry or “3D photography”) is becoming an increasingly popular tool for quantification of the face, in clinical contexts as well as for research. The modality is easy to apply and is free from motion artifacts and harmful radiation. It is an obvious choice for comprehensive documentation and analysis of facial development and treatment progression and outcome in individuals with juvenile idiopathic arthritis (JIA). An acquisition protocol for 3D digital surface imaging of children and adolescents with JIA using a 3dMDtrio stereophotogrammetric system is presented. Methodology for processing and analysis of the acquired surfaces is presented and applied to two patient cases in order to illustrate quantification of facial development and asymmetry progression. It is concluded that surface imaging is a powerful technique for monitoring of facial development and treatment outcome, and it is proposed that the method would be suitable for multi-center comparisons of treatment outcomes.