Comparative Study of Three-Dimensional Volume Measurement for Facial Fat Grafting.

ABSTRACT The three-dimensional (3D) volume measurement after facial fat grafting is of great significance to plastic surgeons. It has been ascertained that reliable results rely on the accurate measurement of 3D softwares. Some 3D softwares in literatures have proposed various ways to optimize each step of the procedure, including the pre- and post-operative image acquisition, alignment, calculation, and analysis. Good image alignment between pre- and post-scan is essential to quantify the volumetric change. Once the pre- and post-operative image alignment has slightly bias or deviation, the subsequent volume measurement would also be affected. To our knowledge, 2 types of 3D software have been widely applied in clinic, primarily based on the image-automatically alignment and image-manually alignment. This study aimed to compare the accuracy, repeatability, and reproducibility of the Geomagic Qualify 12.0 software and the 3-Matic 7.0 software in a relatively ideal model of virtual facial fat grafting. A simulated facial fat grafting was first performed for 10 preoperative patients diagnosed with progressive hemifacial atrophy, and the known volumetric change was named as the true value (T value). Then, the facial volumetric change of every case was remeasured 10 times with above 2 kinds of software separately. The mean volumetric change was calculated as Q value and M value. The paired t test, intraclass correlation coefficient, and Bland-Altman analysis showed that the Geomagic Qualify 12.0 software demonstrated a statistically higher accuracy, repeatability, and reproducibility in comparison with the 3-Matic 7.0 software.