"Utility of Smartphone-based Three-dimensional Surface Imaging for Digital Facial Anthropometry"

Robin Hartmann; Felix Nieberle; Christoph Palm; Vanessa Brébant; Lukas Prantl; Reinald Kuehle; Torsten E Reichert; Juergen Taxis; Tobias Ettl

doi:10.1016/j.jpra.2024.01.014

"Utility of Smartphone-based Three-dimensional Surface Imaging for Digital Facial Anthropometry"

JPRAS Open. 2024 Jan 30:39:330-343. doi: 10.1016/j.jpra.2024.01.014. eCollection 2024 Mar.

Authors

Robin Hartmann¹, Felix Nieberle¹, Christoph Palm^{2

3}, Vanessa Brébant⁴, Lukas Prantl⁴, Reinald Kuehle⁵, Torsten E Reichert¹, Juergen Taxis¹, Tobias Ettl¹

Affiliations

¹ University Hospital Regensburg Clinic and Polyclinic for Oral and Maxillofacial Surgery, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Germany.
² Regensburg Medical Image Computing (ReMIC), Ostbayerische Technische Hochschule Regensburg (OTH Regensburg), Galgenbergstr. 32, 93053, Regensburg.
³ Regensburg Center of Biomedical Engineering (RCBE), OTH Regensburg and Regensburg University, Galgenbergstr. 32, 93053, Regensburg.
⁴ University Center of Plastic, Aesthetic, Hand and Reconstructive Surgery, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg, Germany.
⁵ University of Heidelberg, Department of Oral and Maxillofacial Surgery, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany.

Abstract

Background: The utilization of three-dimensional (3D) surface imaging for facial anthropometry is a significant asset for patients undergoing maxillofacial surgery. Notably, there have been recent advancements in smartphone technology that enable 3D surface imaging.In this study, anthropometric assessments of the face were performed using a smartphone and a sophisticated 3D surface imaging system.

Methods: 30 healthy volunteers (15 females and 15 males) were included in the study. An iPhone 14 Pro (Apple Inc., USA) using the application 3D Scanner App (Laan Consulting Corp., USA) and the Vectra M5 (Canfield Scientific, USA) were employed to create 3D surface models. For each participant, 19 anthropometric measurements were conducted on the 3D surface models. Subsequently, the anthropometric measurements generated by the two approaches were compared. The statistical techniques employed included the paired t-test, paired Wilcoxon signed-rank test, Bland-Altman analysis, and calculation of the intraclass correlation coefficient (ICC).

Results: All measurements showed excellent agreement between smartphone-based and Vectra M5-based measurements (ICC between 0.85 and 0.97). Statistical analysis revealed no statistically significant differences in the central tendencies for 17 of the 19 linear measurements. Despite the excellent agreement found, Bland-Altman analysis revealed that the 95% limits of agreement between the two methods exceeded ±3 mm for the majority of measurements.

Conclusion: Digital facial anthropometry using smartphones can serve as a valuable supplementary tool for surgeons, enhancing their communication with patients. However, the proposed data suggest that digital facial anthropometry using smartphones may not yet be suitable for certain diagnostic purposes that require high accuracy.

Keywords: Digital anthropometry; Facial anthropometry; Maxillofacial surgery; Smartphone-based surface imaging; Stereophotogrammetry; Three-dimensional surface imaging.