Radiomics and Artificial Intelligence Study of Masseter Muscle Segmentation in Patients With Hemifacial Microsomia

Background:Hemifacial microsomia (HFM) is one of the most common congenital craniofacial condition often accompanied by masseter muscle involvement. U-Net neural convolution network for masseter segmentation is expected to achieve an efficient evaluation of masseter muscle. Methods:A database was established with 108 patients with HFM from June 2012 to June 2019 in our center. Demographic data, OMENS classification, and 1-mm layer thick 3-dimensional computed tomography were included. Two radiologists manually segmented masseter muscles in a consensus reading as the ground truth. A test set of 20 cases was duplicated into 2 groups: an experimental group with the intelligent algorithm and a control group with manual segmentation. The U-net follows the design of 3D RoI-Aware U-Net with overlapping window strategy and references to our previous study of masseter segmentation in a healthy population system. Sorensen dice-similarity coefficient (DSC) muscle volume, average surface distance, recall, and time were used to validate compared with the ground truth. Results:The mean DSC value of 0.794 +/- 0.028 for the experiment group was compared with the manual segmentation (0.885 +/- 0.118) with alpha=0.05 and a noninferiority margin of 15%. In addition, higher DSC was reported in patients with milder mandible deformity (r=0.824, P<0.05). Moreover, intelligent automatic segmentation takes only 6.4 seconds showing great efficiency. Conclusions:We first proposed a U-net neural convolutional network and achieved automatic segmentation of masseter muscles in patients with HFM. It is a great attempt at intelligent diagnosis and evaluation of craniofacial diseases.

Automated summary

A database was established to evaluate masseter muscle using the U-Net neural convolution network. The results showed that intelligent automatic segmentation only took 6.4 seconds and achieved efficient evaluation. This study represents a significant attempt at intelligent diagnosis and evaluation of craniofacial diseases.