UNASSIGNED: Mandible distraction osteogenesis (MDO) is widely used to reconstruct the mandible in patients with mild Hemifacial microsomia (HFM). However, the masseter\'s response to mandible distraction remains unclear.
UNASSIGNED: In this study, we analyze the effect of the surgical intervention on masseter muscle by a retrospective analysis. The procedure consisted of a five-day latent period, a three-week distraction period, and a six-month consolidation period. CT data were manually segmented and measured with Mimics software before surgery, within 3 months, and more than 1 year postoperatively. Masseter volume, masseter length, masseter width, and mandible ramus height were measured and analyzed using paired t-test, Pearson, and Spearman correlation analysis.
UNASSIGNED: We included 21 patients with HFM who underwent mandible distraction osteogenesis from 2015 to 2020. The masseter volume on the affected side increased immediately after surgery from (6,505.33 ± 3,671.95) mm3 to (10,194.60 ± 5638.79) mm3, but decreased to (8,148.38 ± 3,472.57) mm3 at the second follow-up correlated to mandible ramus height (r = 0.395, P = 0.038). A similar trend was observed in changes in masseter length. Symmetry and width of masseter muscle had no longitudinal statistical significance.
UNASSIGNED: Masseter muscle involvement benefits from MDO in the short term. To achieve long-term efficacy, more attention should be paid to muscle reconstruction.

BACKGROUND: This study aimed to prospectively investigate the reference values for masseter muscle thickness and hardness using ultrasonography and shear wave elastography, respectively, in patients with hemifacial microsomia (HFM).
METHODS: We enrolled 51 patients, aged 5-20 years, with HFM including 31 males and 20 females. The upper-lower, left-right, and anterior-posterior diameters of 102 masseter muscles and stiffness of 98 masseter muscles were determined by examining the unaffected and affected sides of each participant\'s face.
RESULTS: The upper-lower, left-right, and anterior-posterior diameters of the masseter muscle were significantly smaller at rest (4.26 ± 0.83, 2.94 ± 0.75, and- 0.80 ± 0.25 cm, respectively) and during contraction (3.95 ± 0.78, 2.71 ± 0.78, and 0.87 ± 0.29 cm, respectively) in the affected side than those in the healthy side (5.45 ± 0.66, 3.87 ± 0.49, and 0.97 ± 0.20 cm, respectively, at rest and 4.99 ± 0.45, 3.49 ± 0.53, and 1.07 ± 0.23 cm, respectively, during contraction, p < 0.05). In the resting state, the hardness of the masseter muscle on the affected side (0.77 ± 0.66 m/s) was significantly greater than that on the healthy side (0.42 ± 0.41 m/s; p < 0.05). The magnitude of changes in the upper-lower, left-right, and anterior-posterior diameters of the biting muscle in the occlusal state were significantly smaller on the affected side (-0.30 ± 0.27, -0.23 ± 0.17, and 0.08 ± 0.08 cm, respectively) than those in the healthy side (-0.47 ± 0.38, -0.37 ± 0.25, and 0.10 ± 0.12 cm, respectively, p < 0.05).
CONCLUSIONS: The knowledge of these values allows for better understanding of the disease characteristics of HFM, which may be used for its diagnosis, treatment, and prognosis. Patients experiencing different severity levels exhibited significant differences in the morphology and function of the masseter muscle on the affected-side (p < 0.05).
METHODS: Level III.

Hemifacial microsomia (HFM) is a rare congenital genetic syndrome primarily affecting the first and second pharyngeal arches, leading to defects in the mandible, external ear, and middle ear. The pathogenic genes remain largely unidentified. Whole-exome sequencing (WES) was conducted on 12 HFM probands and their unaffected biological parents. Predictive structural analysis of the target gene was conducted using PSIPRED (v3.3) and SWISS-MODEL, while STRING facilitated protein-to-protein interaction predictions. CRISPR/Cas9 was applied for gene knockout in zebrafish. In situ hybridization (ISH) was employed to examine the spatiotemporal expression of the target gene and neural crest cell (NCC) markers. Immunofluorescence with PH3 and TUNEL assays were used to assess cell proliferation and apoptosis. RNA sequencing was performed on mutant and control embryos, with rescue experiments involving target mRNA injections and specific gene knockouts. CDC27 was identified as a novel candidate gene for HFM, with four nonsynonymous de novo variants detected in three unrelated probands. Structural predictions indicated significant alterations in the secondary and tertiary structures of CDC27. cdc27 knockout in zebrafish resulted in craniofacial malformation, spine deformity, and cardiac edema, mirroring typical HFM phenotypes. Abnormalities in somatic cell apoptosis, reduced NCC proliferation in pharyngeal arches, and chondrocyte differentiation issues were observed in cdc27-/- mutants. cdc27 mRNA injections and cdkn1a or tp53 knockout significantly rescued pharyngeal arch cartilage dysplasia, while sox9a mRNA administration partially restored the defective phenotypes. Our findings suggest a functional link between CDC27 and HFM, primarily through the inhibition of CNCC proliferation and disruption of pharyngeal chondrocyte differentiation.

BACKGROUND: To report a case of a 4-year-old patient with Goldenhar syndrome.
METHODS: The author presents a rare case report involving a 4-year-old boy with multiple malformations. A comprehensive examination showed that the patient primarily had a limbal dermoid. He also has bilateral microtia and ear canal deformities. The skull CT scan and spine X-ray showed Maxillofacial Abnormalities and scoliosis. Whole Exome Sequencing revealed potential gene variations related to microtia. Although certain circumstances prevented us from initiating follow-up treatment for the patient, we have provided a detailed account of the diagnostic methodologies used for this condition.
CONCLUSIONS: Goldenhar syndrome is a congenital condition, predominantly presenting as sporadic cases. Its diagnosis and management typically necessitate the involvement of multiple disciplines, including otolaryngology and craniofacial surgery. The syndrome encompasses a variety of craniofacial features, which can facilitate early diagnosis and guide subsequent therapeutic interventions.

Hemifacial Microsomia (HFM) is the second most common congenital craniofacial malformation syndrome, and the complexity of HFM makes its treatment challenging. The present study aimed to introduce a new approach of utilization of virtual surgical planning (VSP) and 3D-printed surgical adjuncts for maxillofacial reconstruction. Five HFM patients were included in this study. All participants were provided with a full VSP, including the design of osteotomy lines, the design and fabrication of 3D-printed cutting guides, fixation plates, and titanium mesh for implantation. With the assistance of 3D-printed cutting guides and fixation plates, the orbital deformities were corrected, and a 3D-printed titanium mesh combined with iliac cancellous bone graft was applied to reconstruct the zygomatic arch. The surgical accuracy, effectiveness, and bone absorption rate were evaluated. All patients completed the entirely digital treatment process without experiencing severe complications. The surgical adjuncts were effective in aligning the movement of the bone segments with the surgical plan, resulting in mean 3D deviations (1.0681 ± 0.15 mm) and maximum 3D deviations (3.1127 ± 0.44 mm). The image fusion results showed that the patients\' postoperative position of the maxilla, zygoma, and orbital rim was consistent with the virtual surgical plan, with only a slight increase in the area of bone grafting. The postoperative measurements showed significant improvement in the asymmetry indices of Er (AI of Er: from 17.91 ± 3.732 to 5.427 ± 1.389 mm, p = 0.0001) and FZ (AI of FZ: from 7.581 ± 1.435 to 4.070 ± 1.028 mm, p = 0.0009) points. In addition, the observed bone resorption rate at the 6-month follow-up across the five patients was 45.24% ± 3.13%. In conclusion, the application of VSP and 3D-printed surgical adjuncts demonstrates significant value in enhancing the precision and effectiveness of surgical treatments for HFM. A 3D-printed titanium mesh combined with iliac cancellous bone graft can be considered an ideal alternative for the reconstruction of the zygomatic arch.

OBJECTIVE: This study aimed to investigate the prevalence of obstructive sleep apnoea (OSA) in patients with craniofacial microsomia (CFM) through polysomnography (PSG) and the relationship with the severity of CFM.
METHODS: This study reviewed patients of CFM with pre-operative PSG data between January 2005 and September 2023. Patients were grouped according to the Pruzansky-Kaban classification. OSA was diagnosed and severity was assessed by the obstructive apnea-hypopnea index. The Pediatric Sleep Questionnaire was used to investigate OSA-related signs and symptoms. The χ 2 test and Fisher\'s exact test were used to compare between groups. Univariate logistic regression was used to identify risk factors associated with OSA. A p-value less than 0.05 was considered statistically significant.
RESULTS: A total of 121 patients with CFM were included in the study with 3 bilateral and 118 unilateral patients. In total, 86 patients (71.07%) were diagnosed with OSA. The prevalence of OSA in type IIa, type IIb and type III was 72.97%, 78.33%, and 47.62%. There was no statistically significant difference in the prevalence of OSA between type IIa and type IIb (p > .05). The difference in the prevalence of OSA between type III and type II was statistically significant (p < .05). Snoring was the most common symptom among the patients of CFM with OSA.
CONCLUSIONS: Patients with CFM have a higher incidence of OSA based on PSG in type II and type III patients. The incidence of OSA did not correlate positively with the severity of CFM, with type III patients having certain particularities.

UNASSIGNED: To preliminarily verify the effectiveness of self-designed artificial condyle-mandibular distraction (AC-MD) complex in the treatment of Pruzansky type ⅡB and Ⅲ hemifacial microsomia (HFM) through model test.
UNASSIGNED: Five children with Pruzansky type ⅡB and Ⅲ HFM who were treated with mandibular distraction osteogenesis (MDO) between December 2016 and December 2021 were selected as the subjects. There were 3 boys and 2 girls wih an average age of 8.4 years (range, 6-10 years). Virtual surgery and model test of AC-MD complex were performed according to preoperative skull CT of children. The model was obtained by three-dimensional (3D) printing according to the children\'s CT data at a ratio of 1∶1. The occlusal guide plate was designed and 3D printed according to the children\'s toothpaste model. The results of the model test and the virtual surgery were matched in three dimensions to calculate the error of the residual condyle on the affected side, and the model test was matched with the actual skull CT after MDO to measure and compare the inclination rotation of the mandible, the distance between the condylar of the healthy side and the residual condyle of the affected side, and the lengthening length of the mandible.
UNASSIGNED: The error of residual condyle was (1.07±0.78) mm. The inclination rotation of the mandible, the distance between the condylar of the healthy side and the residual condyle of the affected side, and the lengthening length of the mandible after 3D printing model test were significantly larger than those after MDO ( P<0.05).
UNASSIGNED: In the model test, the implantation of AC-MD complex can immediately rotate the mandible to the horizontal position and improve facial symmetry, and the residual condyle segment can be guided close to the articular fossa or the preset pseudoarticular position of the skull base after operation.
UNASSIGNED: 通过模型试验初步验证自行设计的人工髁突-下颌骨延长器（artificial condyle-mandibular distractor，AC-MD）复合体在Pruzansky ⅡB、Ⅲ型半侧颜面短小症（hemifacial microsomia，HFM）治疗中的有效性。.
UNASSIGNED: 选取2016年12月—2021年12月采用下颌骨牵引成骨术（mandibular distraction osteogenesis，MDO）治疗的5例Pruzansky ⅡB、Ⅲ型HFM患儿作为研究对象。其中男3例，女2例；年龄6～10岁，平均8.4岁。根据患儿术前头颅CT行AC-MD复合体虚拟手术和模型试验，模型依据患儿CT数据按1∶1经3D打印所得，结合患儿口腔石膏模型设计并3D打印模型试验所需的咬合导板。将模型试验与虚拟手术结果行三维配比，测算患侧残突整体误差；将模型试验与患儿实际MDO术后头颅CT行三维配比，测量并比较下颌骨倾斜度转动、健侧髁突-患侧残突距离及下颌骨延长长度。.
UNASSIGNED: 残突整体误差为（1.07±0.78）mm。3D打印模型手术后下颌骨倾斜度转动、健侧髁突-患侧残突距离及下颌骨延长长度均显著大于患儿实际MDO术后各相应指标，差异有统计学意义（ P<0.05）。.
UNASSIGNED: 在模型试验中，AC-MD复合体植入可即刻旋转下颌骨至水平位、改善面部对称性；术后可导引残突骨段接近关节窝或颅底预设假关节位。.

Object: Three-stage expansion method represents the most common form of microtia reconstruction in hemifacial microsomia (HFM). Although the complication related expander has lowered owing to the current advances, bony depression in mastoid region in microtia patients with hemifacial microsomia was observed in clinical work. The aim of this study was to quantify bony depression after retroauricular expander implantation and identify associated factors. Methods: 42 patients were enrolled and studied prospectively utilizing 3-dimensional (3D) evaluation. Craniofacial computed tomography (CT) was performed before the first (pre-expansion) and the second stage (post-expansion) and 3D quantification was done to quantify bony depression in mastoid region by using CT data. Univariate analysis was performed to identify factors associated with bony depression in mastoid region. Results: The mean level of mastoid depression was 0.83 mm (range: 0.07-4.08 mm), and the max level of mastoid depression was 1.40 mm (range: 0.20-6.65 mm). In univariate analysis, capsular duration of expansion and expansion volume were associated factors with mastoid depression. Conclusion: This study showed the possibility of mastoid depression following expander implantation for microtia reconstruction in hemifacial microsomia. Plastic surgeons should be aware of the possibility and associated factors of bony depression in mastoid region following expander implantation to optimize microtia reconstruction for patients with HFM.

Objective: Microtia patients with hemifacial microsomia (HFM) have a host of distinct anatomical disorder of skeletal and soft tissue asymmetries. The purpose of this study was to assess soft tissue discrepancies in microtia patients with HFM and their correlation with skeletal discrepancies. Methods: A total of 42 patients were enrolled and studied prospectively using a 3-dimensional superimposition and color mapping of the soft and hard tissues. Mirroring techniques created perfectly symmetric models for comparison. Differences between affected and normal sides were evaluated in 5 areas: retroauricular mastoid, malar, maxillary frontal, mandibular frontal, and gonion areas. Pearson correlations were used to assess the relationship between skeletal and soft tissue asymmetry. Results: Hard tissue asymmetry ranged from 0.79 mm (mandibular frontal) to 1.29 mm (malar), while soft tissue asymmetry ranged from 1.34 mm (maxillary frontal) to 5.26 mm (retroauricular mastoid). Correlations between skeletal and soft tissue asymmetry varied, with the strongest correlation observed at the retroauricular mastoid area and the weakest at the maxillary frontal area. Conclusion: There was a high correlation between bone and soft tissue hypoplasia at the retroauricular mastoid area, while the other evaluated areas showed poor correlation between skeletal and soft tissue asymmetries. Clinicians should assess each component separately for optimal treatment planning in microtia patients with HFM.

UNASSIGNED: Mandibular distraction osteogenesis, a recommended therapy for hemifacial microsomia, has brought much agony because of its traumatic procedures and peri-osteotomy complications. Our study aims to retrospectively compare piezoelectric osteotome with conventional reciprocal bone saw for hemifacial microsomia patients and validate its meliority in operability, surgical risks and patient outcomes.
UNASSIGNED: All patients included underwent osteotomies conducted by either piezosurgery or bone saw. Information of intraoperative blood loss, operation duration, postoperative pain and complications was collected from patient files, ward round inspections and follow-ups.
UNASSIGNED: Among all 40 patients, 13 underwent piezo-osteotomy. Piezosurgery performed better than conventional reciprocal bone saw in decreasing intraoperative blood loss (p < 0.001) and operation duration (p = 0.030). No significant difference was found in hospitalization duration, total expenses or complication rates between two groups. There were positive relations between operation duration and intraoperative blood loss (p = 0.042), and between hospitalization duration and total expenses (p = 0.0096). Postoperative pain scores of both groups declined over time while the piezosurgery group had a statistically significant tendency (p = 0.006) to suffer less than the conventional group.
UNASSIGNED: Piezosurgery diminishes intraoperative blood loss, operative duration, and postoperative pain, making an alternative to conventional osteotomes to mitigate patients\' and families\' peri-osteotomy sufferings, and a more humane solution to HFM.