Correlations Between Mandible Condylar Structures and External Ear Deformities in Hemifacial Microsomia With Three-Dimensional Analysis.

ABSTRACT: This study aimed to explore correlations between mandible and ear deformities and quantitative volumetric relations between condylar structures and external ear in hemifacial microsomia. The authors reconstructed three-dimensional craniofacial models from 212 patients with unilateral hemifacial microsomia (the unaffected side as the controls). Patients were evaluated by Pruzansky-Kaban and Marx classification, and divided into 3 age groups (0-6, 7-12, and >12 years of age). The mandible condylar structures, including condyle and the condylar skeletal unit, were selected (except the classification of the mandibular or ear deformities (M3)). Along with the external ear (except the classification of the mandibular or ear deformities (E4)), their volumes were measured and analyzed. Spearman correlation coefficient analysis was applied. There was a positive correlation between the mandible and ear deformities (r = 0.301, P   <  0.001). Either between the condyle and external ear ( P  = 0.071-0.493) or between the condylar unit and external ear ( P  = 0.080 - 0.488), there were no volumetric relations on the affected side, whereas on the unaffected side were (r = 0.492-0.929 for condyle, r = 0.443-0.929 for the condylar unit, P  < 0.05). In most cases, the condylar structures of the classification of the mandibular or ear deformities (M2b) were significantly smaller than the classification of the mandibular or ear deformities (M2a). Results suggested deformities of mandibular condylar structures and ear did not correlate, although deformities of mandible and ear did. The condylar deformity might develop independently from microtia and be more severe within relatively more abnormal temporomandibular joints.

Hyperbaric CO2 Cryotherapy for Managing Swelling After Mandibular Angle Ostectomy.

ABSTRACT: Postoperative facial swelling after mandibular angle ostectomy is a concern for patients as it affects their quality of life. This study aimed to evaluate the effect of hyperbaric CO2 cryotherapy in relieving postoperative swelling. Thirty-seven patients (mean age: 22.95 ±â€Š3.49 years) who underwent bilateral mandibular angle ostectomy from April to October 2019, were included in this study. A split-mouth design was adopted and through a random sequence, either side of the face was designated as the experimental side. Both received routine nursing care, while the experimental side underwent an additional hyperbaric CO2 cryotherapy treatment. The facial structure was recorded by a 3-dimensional laser scanner pre- and postoperatively. Geomagic Studio was used for alignment, visualization, and quantification of the swelling. The largest deviation value on each side was adopted to assess the overall swelling. Parameters were compared using the paired t-test, and P<0.05 was considered statistically significant. No necrosis of the skin and adjacent structures or other complications occurred in these patients. After the first day of cryotherapy, the deviation in the experimental and the control groups was (8.40 ±â€Š1.95) mm and (10.42 ±â€Š2.03) mm, respectively. The next day, after cryotherapy, the value further reduced to (5.42 ±â€Š1.36) mm and (8.24 ±â€Š2.22) mm for the experimental and control groups, respectively. And the effect remained till the seventh day. No difference was observed in terms of volume of drainage. Hyperbaric CO2 cryotherapy is safe and effective in relieving postoperative swelling and seems to be more effective than the traditional cold-pack treatment after mandibular angle ostectomy.

A new method for cranial vault reconstruction: Augmented reality in synostotic plagiocephaly surgery.

PURPOSE: Augmented reality (AR) is considered to be a valuable tool in craniofacial surgery for preoperative design, intraoperative navigation, and postoperative assessment. Corrective surgery is necessary synostotic plagiocephaly for functional and aesthetic outcomes. Open calvarial reconstruction is a difficult classic surgical procedure with a high accuracy requirement. The purpose of this study was to introduce an AR system application in synostotic plagiocephaly surgery. MATERIALS AND METHODS: Seven plagiocephaly patients (ages 6 months-24 months, average 16.7 months) were enrolled. Preoperative design was accomplished based on three-dimensional computed tomography (CT) data for patients with synostotic plagiocephaly. We completed the registration with the predefined markers through an image registration process preoperatively. Then, we overlaid the registration results into the surgical field to assist surgeons intraoperatively. CT scans were performed postoperatively. Intracranial volume was measured to judge the surgical outcomes. We performed a quantitative craniometric analysis between the planning of the reconstruction and post-operative results, and the main evaluation indicator was the intracranial volume asymmetry. RESULTS: We successfully applied the AR system in patients undergoing synostotic plagiocephaly, providing real-time navigational images of position and orientation information during open calvarial reconstruction surgery in 7 plagiocephaly patients within a span of 5 years. Good appearances were observed after the surgery. Cranial volume asymmetry was decreased from 27.87% to 16.57%, achieving precise intra-operative goals. No significant differences were found between planning and post-operative results. CONCLUSIONS: The AR system can be applied to plagiocephaly procedures guiding to obtain reliable and accurate results via a precise osteotomy.