Intuitive Facial Imaging Method for Evaluation of Postoperative Swelling: A Combination of 3-Dimensional Computed Tomography and Laser Surface Scanning in Orthognathic Surgery

Abstract

Postoperative facial swelling after orthognathic surgery may be prolonged and of concern in some patients. In recent years, there have been several reports of analysis of postoperative facial swelling by volume data; however, such evaluations cannot exclude the possibility of error in the measured point because there are no clear anatomic landmarks on the cheek. Three-dimensional laser scanning is a noninvasive tool that can be used to measure surface changes in soft tissue over time. The aim of this study was to quantify postoperative swelling in orthognathic surgery by fusing surface scanned images with skin images reconstructed from 3-dimensional computed tomography data and identifying a set of reference points on the bone. The study comprised 30 patients undergoing bilateral sagittal split osteotomy. Facial scans were obtained with the Artec Eva Scan imaging system (Data Design, Aichi, Japan) at 9 time points from before surgery to 6months postoperatively. Postoperative scan images were compared with the baseline facial scan obtained 6months postoperatively. On average, 66% of the initial postoperative edema subsided in 1month. After 3months, only 5% of the swelling remained. There were statistically significant correlations between subcutaneous tissue thickness and swelling (P < .0001). We were able to monitor facial swelling after orthognathic surgery with very high precision using the described method. Subcutaneous tissue thickness is an important determinant of facial swelling.