[En Route for Objective Evaluation of Form, Volume, and Symmetry in Plastic Surgery using 3-D Intraoperative Scans]. / Auf dem Weg zur objektiven Evaluation von Form, Volumen und Symmetrie in der Plastischen Chirurgie mittels intraoperativer 3D Scans.

BACKGROUND: There has been ongoing development in the field of 3-dimensional (3-D) Surface Imaging by laser scanner and digital 3-D photography (Photogrammetry) in recent years. Manufacturers tend to make new 3-D cameras compact, light-weighted, mobile, and user-friendly, similar to the development on the smartphone market. Although 3D scans have been used for patient consultations and digital documentation in Plastic Surgery since the 1980, there has been no significant development lately regarding its use for objective assistance during surgery. PATIENTS, MATERIAL AND METHODS: Our research team presents a new intraoperative 3-D scanning method for plastic-surgical procedures with selected mobile 3-D scanner systems. In the future, these might assist surgeons with the pre-, post-, and intraoperative 3-D analysis, choice of therapy, consultation, and documentation. RESULTS: The 3-D scanners were successfully validated for their intraoperative application to several patients. With their introduction, an intraoperative, objective measurement of volume to evaluate form and symmetry was possible. CONCLUSION: In this work, we share our first experience with the intraoperative use of new mobile 3D camera systems, discuss pros and cons, and show selected patient examples.

[3D-imaging and analysis for plastic surgery by smartphone and tablet: an alternative to professional systems?]. / 3D Bilderfassung und Analyse in der Plastischen Chirurgie mit Smartphone und Tablet: eine Alternative zu professionellen Systemen?

BACKGROUND: A new approach of using photographs from smartphones for three-dimensional (3D) imaging was introduced besides the standard high quality 3D camera systems. In this work, we investigated different capture preferences and compared the accuracy of this 3D reconstruction method with manual tape measurement and an established commercial 3D camera system. METHODS: The facial region of one plastic mannequin head was labelled with 21 landmarks. A 3D reference model was captured with the Vectra 3D Imaging System®. In addition, 3D imaging was executed with the Autodesk 123d Catch® application using 16, 12, 9, 6 and 3 pictures from Apple® iPhone 4 s® and iPad® 3rd generation. The accuracy of 3D reconstruction was measured in 2 steps. First, 42 distance measurements from manual tape measurement and the 2 digital systems were compared. Second, the surface-to-surface deviation of different aesthetic units from the Vectra® reference model to Catch® generated models was analysed. For each 3D system the capturing and processing time was measured. RESULTS: The measurement showed no significant (p>0.05) difference between manual tape measurement and both digital distances from the Catch® application and Vectra®. Surface-to-surface deviation to the Vectra® reference model showed sufficient results for the 3D reconstruction of Catch® with 16, 12 and 9 picture sets. Use of 6 and 3 pictures resulted in large deviations. Lateral aesthetic units showed higher deviations than central units. Catch® needed 5 times longer to capture and compute 3D models (average 10 min vs. 2 min). CONCLUSION: The Autodesk 123d Catch® computed models suggests good accuracy of the 3D reconstruction for a standard mannequin model, in comparison to manual tape measurement and the surface-to-surface analysis with a 3D reference model. However, the prolonged capture time with multiple pictures is prone to errors. Further studies are needed to investigate its application and quality in capturing volunteer models. Soon mobile applications may offer an alternative for plastic surgeons to today's cost intensive, stationary 3D camera systems.