Efficacy and safety of adenotonsillectomy in the management of obstructive sleep apnea syndrome in children with Down syndrome: A systematic review and meta-analysis.

Obstructive sleep apnea (OSA) is commonly observed in children with Down syndrome (DS) and may affect their physical and psychological development. Currently, adenotonsillectomy is the first line treatment option for paediatric patients with OSA. However, surgical outcomes for such patients are not satisfactory. In this study, we analysed the efficacy and safety of adenotonsillectomy in the treatment of children with obstructive sleep apnea and Down syndrome. We systematically searched the PubMed, Web of Science, EMBASE, and the Cochrane databases and pooled data from nine relevant studies involving 384 participants. Subsequently, we analysed four outcomes in polysomnography, namely: net postoperative changes in the apnea-hypopnea index (AHI), the minimum oxygen saturation, sleep efficiency, and arousal index. Meta-analysis of the AHI showed a decrease of 7.18 events/h [95% CI (-9.69, -4.67) events/h; p < 0.00001] and an increase in the minimum oxygen saturation of 3.14% [95% CI (1.44, 4.84) %; p = 0.0003]. There was no significant increase in sleep efficiency [MD 1.69%, 95% CI (-0.59, 3.98) %; p = 0.15], but the arousal index significantly decreased by -3.21 events/hour [95% CI (-6.04, -0.38) events/h; p < 0.03]. In addition, the overall success rate was 16% (95% CI, 12%-21%) for postoperative AHI < 1 and 57% (95% CI, 51%-63%) for postoperative AHI <5. The postoperative complications recorded included airway obstruction and bleeding. This study demonstrated the efficacy of adenotonsillectomy as a treatment option for OSA. However, it is important to note that residual OSA and potential postoperative complications require further attention in future studies.

Blind beamforming-based strong interference suppression in underwater acoustic direct-sequence code-division multiple-access systems.

In an underwater acoustic direct-sequence code-division multiple-access (DS-CDMA) system, the performance of the conventional receiver is severely limited by the strong multiple-access interferences, which is due to the near-far effect. In this paper, a time-frequency-time with eigendecomposition-based blind beamformer (TFT-EBB) method is proposed for a distant user to suppress strong interference from a nearby user in DS-CDMA underwater acoustic communications. When the interference level is moderately higher than that of the desired signal, the TFT-EBB method can estimate the composite steering vector of all multipath components of the weak desired user signal via the eigendecomposition of the array covariance matrix at each frequency bin. Then the proposed energy detection-based RAKE receiver is cascaded to achieve multipath diversity, in which it requires less prior information compared with the conventional RAKE receiver. The proposed method is evaluated by using both simulated and field experimental data, which verifies its effectiveness.

Multimodal imaging and electroretinography highlights the role of VEGF in the laser-induced subretinal fibrosis of monkey.

Age-related macular degeneration (AMD) is a leading cause of blindness. Laser-induced nonhuman primate choroidal neovascularization (CNV) is a widely used animal model of neovascular AMD. Subretinal fibrosis (SFb) is the major limiting factor of effective anti-VEGF therapy for neovascular AMD, yet SFb has never been systematically analyzed in the primate CNV model and if VEGF directly affect SFb is unknown. We recruited a large cohort of rhesus macaques to study the occurrence, multimodal imaging and electroretinography (ERG) features, and related cytokines of SFb. Here we show that among 33 rhesus macaques, 88% CNV eyes developed SFb. Spectral domain optical coherence tomography (SD-OCT) identified four types of subretinal hyper-reflective material (SHRM) of SFb in primate. Multimodal imaging is reliable for monitoring SFb and matches the histological results well. Reduced amplitude of oscillatory potentials correlates with the thinning of inner retina layers and is a possible SFb indicator. Iba1+ microglia/macrophage cells infiltrated in the fibrotic lesions, and aqueous cytokine analysis identified four fibrosis-related factors (GM-CSF, IL-10, TGFß2 and VEGF). Unexpectedly, we found sustained expression of VEGF may be an important inducer of SFb, and anti-VEGF therapy actually partially suppresses SFb. Taken together, our data suggest the laser-induced primate SFb model, coupled with multimodal imaging and ERG recording, is a useful system to dissect the pathogenesis and explore the rationale of treatment for SFb; and combined therapy with anti-VEGF and anti-fibrosis agents is necessary for AMD treatment.

Mass spectrometry-based proteomic analysis of FSCN1-interacting proteins in laryngeal squamous cell carcinoma cells.

Fascin actin-bundling protein 1 (FSCN1) is an evolutionarily conserved actin-bundling protein that plays a critical role in cell migration, motility, adhesion, and cellular interactions. Although multiple clinical studies have implicated the expression of FSCN1 in laryngeal squamous cell carcinoma (LSCC) progression, the precise mechanism of FSCN1 in the process has not been clearly elucidated. To define FSCN1 function, we characterized FSCN1­interacting proteins in two cell lines by immunoprecipitation followed by mass spectrometry (MS). After data filtering, 119 proteins with expression in both the Hep-2 and TU-177 cell samples were identified as FSCN1-interacting partners. With in-depth bioinformatics analysis, we linked FSCN1 to critical cellular processes including cell adhesion, glycolysis/gluconeogenesis, regulation of protein ubiquitination, ribosomal RNA processing, and small molecule metabolism. We discuss the interactions between FSCN1 and some of the newly validated partners. The identification of these potential partners of FSCN1 expands our knowledge of the FSCN1 interactome and provides a valuable resource for understanding the functions of this protein in LSCC progression.

One-Year Relapse of Mandibular Distraction for Hemifacial Microsomia Using Masseteric Botulinum Toxin Type A Injections.

BACKGROUND: The relapse of hemifacial microsomia was thought to be highly related to the soft tissue envelope around the mandible angle mainly composed by masseter and medial pterygoid. According to the reason, we tried to apply masseter injection of type A botulinum toxin to weaken the soft envelope tension on the early stage post mandible distraction in adult HFM patients. METHODS: Eight patients diagnosed with HFM were studied and randomly assigned to an experimental or control group. Patients in the experimental group were treated with DO, orthognathic surgeries, autologous fat grafting, and bilateral masseter muscle injection with type A botulinum toxin. The patients in control group were treated with the same procedures as the patients in experimental group except for masseter muscle injection with type A botulinum toxin. The recurrence rates of both groups were evaluated and analyzed after nearly 1 year of follow-up. RESULTS: The mean recurrence rate was 26.30% ±â€Š11.84% (range 7.62%-37.27%) in the 8 patients after 1-year follow-up. The relapse rate was 16.32% ±â€Š7.78% (7.62%-26.22%) in the experimental group and 36.28% ±â€Š1.03% (34.84%-37.27%) in the control group. There was a significant difference (P = 0.002) between the experimental group and the control group. CONCLUSIONS: The combination of DO, orthognathic surgeries, autologous fat particle transplantation, and masseter muscle type A botulinum toxin injection technique could be a comprehensive treatment plan for adult patients of HFM. Furthermore, masseter injection of type A botulinum toxin might be an alternative method to reduce the early recurrence rate of postoperative adult patients of HFM.

Evaluation of human platelet lysate and dimethyl sulfoxide as cryoprotectants for the cryopreservation of human adipose-derived stem cells.

Cryopreservation provides an effective technique to maintain the functional properties of human adipose-derived stem cells (ASCs). Dimethylsulfoxide (DMSO) and fetal bovine serum (FBS) are frequently used as cryoprotectants for this purpose. However, the use of DMSO can result in adverse effects and toxic reactions and FBS can introduce risks of viral, prion, zoonose contaminations and evoke immune responses after injection. It is therefore crucial to reduce DMSO concentrations and use serum-free solution in the cryopreservation process. Human platelet lysate (PL) is a promising candidate for use as an alternative to DMSO and FBS. Therefore, in this study, with an aim to identify a cryoprotective agent for ASC cryopreservation, we determined the viability, proliferation potential, phenotype, and differentiation potential of fresh ASCs and ASCs cryopreserved using different combinations of three cryoprotective agents: fetal bovine serum (FBS), dimethylsulfoxide (DMSO), and human platelet lysate (PL). The viability of the ASCs cryopreserved with 90% FBS and 10% DMSO, 95% FBS and 5% DMSO, and 97% PL and 3% DMSO was >80%, and the proliferation potentials, cell phenotypes, and differentiation potentials of these groups were similar to those of fresh ASCs. Together, our findings suggest that a combination of 97% PL and 3% DMSO is an ideal cryoprotective agent for the efficient cryopreservation of human ASCs.

A Rare Eyeball Luxation After Cranioplasty and a Four-Year Follow-Up.

A rare patient of reducible eyeball luxation after cranioplasty in a child Crouzon syndrome was reported. To remedy the patient's chronic intracranial hypertension and brachycephaly, orbitofrontal advancement and cranial vault remodeling were carried out. About 25 days of postoperation, an acute eyeball luxation was observed, with the presence of a subcutaneous accumulation of liquid in the bilateral temporal regions. The dislocated eyeballs were brought back by applying gentle manual pressure. The patient received a conservative treatment without a tarsorrhaphy. The dislocation recurrence never occurred again. In a 4-year follow-up, it was shown that the child's vision was normal and proptosis was improved by series craniofacial reconstructions.

A new three-dimensional measurement in evaluating the cranial asymmetry caused by craniosynostosis.

PURPOSE: To present a modified cranial vault asymmetry index, evaluate it by measuring the asymmetry of the skull shape with craniosynostosis and by assessing the surgical outcome quantitatively, compare it with traditional cranial vault asymmetry index (CVAI) and discuss its advantages and shortcomings. METHODS: Based on the traditional CVAI, anterior cranial vault asymmetry index (ACVAI) and posterior cranial vault asymmetry index (PCVAI) were proposed to evaluate surgical outcomes. We measured CVAI, ACVAI and PCVAI on the reconstructed three-dimensional computed tomography images to analyze the degree of the malformation and assess the surgical outcomes. The new method was compared with the traditional one, and statistical analysis was performed. RESULTS: Using Wilcoxon Rank Sum Test, preoperative ACVAI compared to postoperative one is statistically significant (p = 0.018), whereas, the p value for CVAI is 0.128 > 0.05. CONCLUSIONS: The ACVAI and PCVAI as modified can better describe the degree of cranial vault asymmetry compared with CVAI. It is also a more reliable index to assess the surgical outcomes quantitatively.

Mandibular distraction combined with orthognathic techniques for the correction of severe adult mandibular hypoplasia.

BACKGROUND: Mandibular hypoplasia may result from congenital deformities or trauma or infection during the early stage of facial skeleton development. Deficiencies in the growth of the mandible can not only cause various degrees of facial deformity but also affect breathing and occlusal function. Here, we report our experiences with mandibular distraction combined with orthognathic surgical techniques for the treatment of severe adult mandibular hypoplasia. METHODS: Cephalometric analysis was conducted in all patients for quantitative evaluation. A computer-assisted surgical simulation was prepared before distraction. According to the simulation data, an operative osteotomy guide plate was designed and three-dimensionally printed with photosensitive resin. With the help of the guide plate, the osteotomy line was precisely placed. An internal distractor was then placed through an extraoral incision created under general anesthesia. Distraction began after 7 days of latency at the rate of 1 mm/d. After a 6- to 8-month consolidation period, the distractor was removed. At the same time, genioplasty and/or subapical osteotomy was performed to correct the patient's crossbite and improve the facial contour for bilateral mandibular hypoplasia. For unilateral mandibular hypoplasia, a Le Fort I osteotomy was performed to correct the open bite on the affected side, whereas a mandibular outer cortex excision was performed on the unaffected side to improve lower facial symmetry. RESULTS: The mandible symmetry and chin protrusion were efficiently improved in all 36 patients (mean age, 20.3 y). No facial nerve palsy was reported, nor were there complaints about postoperative facial scarring. The postoperative infection rate was 2.8%. The distance of lengthening was 26.2 (2.8) mm. The increased ramus length on the affected side was 18.9 (9.3) mm. At the end of the consolidation period (T2), the affected mandibular ramus length increased by 46.3% (23.6%) in unilateral distraction osteogenesis; however, it decreased by 18.6% (12.4%) after device removal (T3). For bilateral distraction osteogenesis, condylion-gonion increased by 34.0% (50.0%) in T2 but had no significant change in T3. CONCLUSION: Complicated mandibular hypoplasia can be well corrected with mandibular distraction combined with orthognathic surgery.

Imaging findings of primary epithelioid sarcoma of adrenal gland: a case report and literature review.

Epithelioid sarcoma (ES) is a rare soft tissue malignant tumor with an uncertain histogenetic origin. It usually arises in soft tissues of the extremities, while ES in adrenal gland is extremely rare. There is no special clinical manifestation in the early stage, so it may be misdiagnosed and delay the treatment. We reported a 69-year-old male with an adrenal ES. The tumor was completely resected, and two months later, positron emission tomography-computed tomography(PET/CT) noted recurrence at the tumor bed and multiple metastases. The patient has been treated with chemotherapy with good effects. We summarize the radiological findings and immunohistochemical indexes of primary epithelioid sarcoma of adrenal gland, which may be useful to promote disease awareness and help to distinguish among other lesions.

Accident entry of titanium screw into the sphenoid sinus during paranasal augmentation with porous polyethylene implant.

We report a rare case of accident entry of titanium screw into the sphenoid sinus during paranasal augmentation with porous polyethylene implant. The screw was finally retrieved from the sphenoid sinus by a nasal endoscope. We emphasize that, on this surgery region, the simple fixation skill must be performed delicately. Otherwise, an adverse event may still happen.

Atorvastatin regulates the migration and invasion of prostate cancer through the epithelial-mesenchymal transformation and matrix metalloproteinase pathways.

PURPOSE: Our purpose was to verify the effects of atorvastatin (ATO) on prostate cancer (PCa) proliferation, apoptosis, invasion, and metastasis and to further explore the drug's mechanism of action. MATERIALS AND METHODS: We used cell counting kit-8 (CCK8) and clone formation experiments to study the effect of ATO on the proliferation of PC3 cells. Flow cytometry and Hoechst 33342 staining were used to detect cell apoptosis. Cell migration and invasion were detected through wound healing experiments and transwell experiments. Western blotting was applied to detect apoptosis-related proteins (BAX, Bcl-2, PARP, and Caspase-3), epithelial-mesenchymal transformation (EMT) proteins, and matrix metalloproteinase (MMP) expression. A mouse xenograft tumor model was established, and tumor volume and weight were determined. The expression levels of the above-mentioned proteins were determined through western blot. RESULTS: ATO inhibited PC-3 cell proliferation and promoted cell apoptosis in a dose-dependent manner. ATO significantly up-regulated the expression of BAX, PARP, and Caspase-3 and inhibited the expression of Bcl-2. Wound healing and transwell experiments showed that ATO inhibited invasion and metastasis in PC-3 cells, possibly because ATO could inhibit the EMT and the expression of MMPs in PC-3 cells. Studies in nude mice showed that ATO significantly reduced tumor volume and weight; the expression levels of related proteins were consistent with the in vitro results. CONCLUSIONS: ATO inhibits the occurrence and development of PCa and regulates the migration and invasion of PCa cells by inhibiting the EMT and MMPs.

The expression profile of plasmatic exosomal lncRNAs in early-onset preeclampsia by sequencing.

Identification of the expression profile of exosomal lncRNAs in plasma from PE patients to provide new insights into the molecular mechanism. Five pregnant patients with early-onset severe PE were included in the PE group and 5 normal pregnant patients were included in the control group in the training cohort. Differential expression of genes were identified between the two groups, and were verified in plasma exosomes from 12 additional pregnant patients with EPE and 12 normal pregnant patients. KEGG pathway analysis and GO enrichment analysis were performed using online prediction databases to construct a lncRNA-miRNA-mRNA co-expression network. From there a panel of candidate lncRNAs was selected and validated via quantitative PCR in the two groups. In the 289 differential lncRNA, 155 were up-regulated and 134 were down-regulated. Bioinformatics enrichment analysis demonstrated that the target genes of differential expression of lncRNAs were enriched in 159 pathways with P < 0.05, including cancer, metabolic and PI3K-Akt signaling pathways. Three lncRNAs exhibited significant differential expressed in exosomes between the two groups. A lncRNA-miRNA-mRNA co-expression network analysis showed that ENST00000559730-hsa-miR-661-NUDT16 was the most frequently associated with susceptibility-relation of PE. The significant differences of plasmatic exosomal lncRNA expression between normal pregnant women and early-onset severe PE patients suggest that lncRNA may participate in the pathogenetic process of PE. Our study provides a preliminary bioinformatic foundation in order to find PE markers in plasma which further increase the sample size, and continue to verify the function of lncRNA in vitro.

Pyrite-embedded porous carbon nanocatalysts assembled in polyvinylidene difluoride membrane for organic pollutant oxidation.

FeS2-embedded in porous carbon (FeS2/C) was prepared by simultaneous sulfidation and carbonization of an iron-based metal-organic framework precursor, and subsequently immobilized in polyvinylidene fluoride membranes (FeS2/C@PVDF) for organics removal via peroxymonosulfate (PMS) activation. The composition, structure, and morphology of the FeS2/C@PVDF membrane were extensively characterized. Scanning electron microscopy images manifest that the FeS2/C nanoparticles with an average diameter of 40 nm are assembled on the external and internal membrane surface. The as-prepared FeS2/C@PVDF membrane exhibits excellent performances over a wide pH range of 1.53-9.50, exceeding carbon-free syn-FeS2@PVDF. The effective degradation could be improved by inner pyrite FeS2 cores and thus enhanced the electron transfer between carbon shell and PMS. Electron paramagnetic resonance and quenching experiments elucidated that radical (HO∙, SO4∙-) and nonradical (1O2) species were the predominant reactive oxidants. In addition, FeS2/C@PVDF exhibited high stability with low Fe leaching (0.377 mg/L) owing to the effective protection of the outer carbon skeleton. Plentiful porosity of PVDF membranes not only affords a controlled size and confined uniform distribution of the immobilized FeS2/C nanoparticles, but also enables a persistent exposure of active sites and enhanced mass transfer efficiency. Our findings demonstrate a promise for utilizing the novel FeS2/C@PVDF membrane as an efficient catalyst for the environmental cleanup.

Immune Microenvironment of Thyroid Cancer.

Thyroid cancer (TC) is a highly heterogeneous endocrine malignancy with an increased incidence in women than in men. Previous studies regarding the pathogenesis of TC focused on the pathological changes of the tumor cells while ignoring the importance of the mesenchymal cells in tumor microenvironment. However, more recently, the stable environment provided by the interaction of thyroid cancer cells with the peri-tumoral stroma has been widely studied. Studies have shown that components of an individual's immune system are closely related to the occurrence, invasion, and metastasis of TC, which may affect response to treatment and prognosis of the patients. This article presents a comprehensive review of the immune cells, secreted soluble mediators and immune checkpoints in the immune microenvironment, mechanisms that promoting TC cells immune evasion and existing immunotherapy strategies. Besides it provides new strategies for TC prognosis prediction and immunotherapy.

Nonprecious bimetallic (Mo, Fe)-N/C nanostructures loaded on PVDF membrane for toxic CrVI reduction from water.

Nonprecious bimetallic molybdenum and iron embedded into N-doped carbon (MoFe-NC) hybrids were designed and fabricated by pyrolysis of mixed precursors and then immobilized on poly (vinylidene fluoride) (PVDF) films via a phase inversion process to obtain novel catalytic membranes (MoFe-NC@PVDF) for toxic CrVI reduction. The catalytic membranes are highly active for aqueous CrVI reduction using formic acid (FA) as a sacrificial electron donor under mild conditions. The results demonstrated that the parameters of synthesis process can efficiently adjust the morphology and textural properties of the as-synthesized MoFe-NC@PVDF membrane, and thus have a significant impact on the catalytic behavior. CrVI reduction rates significantly increased with increasing FA concentrations (0.234-0.936 M) and reaction temperature (5-35℃), but declined with the increase of CrVI concentrations (5-40 mg/L) and pH values of solution (1.87-4.62). Mo-Nx, Fe-Nx, and C-Nx are the active sites, boosting the dissociation of FA molecules into active H* species for effective catalytic reduction of CrVI. The catalytic PVDF membrane exhibited distinct porous structure and numerous interaction sites, which not only stabilized metallic nanoparticles, but also promoted mass transfer across the membrane. This cost-effective catalytic membrane provides a new approach toward the treatment of CrVI-containing water.

Vitreous cryopreservation of tissue engineered bone composed of bone marrow mesenchymal stem cells and partially demineralized bone matrix.

Cryopreservation of tissue engineered products by maintaining their structure and function is a prerequisite for large-scale clinical applications. In this study, we examined the feasibility of cryopreservation of tissue engineered bone (TEB) composed of osteo-induced canine bone marrow mesenchymal stem cells (cBMSCs) and partially demineralized bone matrix (pDBM) scaffold by vitrification. A novel vitreous solution named as VS442 containing 40% dimethyl-sulfoxide (DMSO), 40% EuroCollins (EC) solution and 20% basic culture medium (BCM) was developed. After being cultured in vitro for 8 days, cell/scaffold complex in VS442 was subjected to vitreous preservation for 7 days and 3 months, respectively. Cell viability, proliferation and osteogenic differentiation of cBMSCs in TEB after vitreous cryopreservation were examined with parallel comparisons being made with those cryopreserved in VS55 vitreous solution. Compared with that cryopreserved in VS55, cell viability and subsequent proliferative ability of TEB in VS442 after being rewarmed were significantly higher as detected by live/dead staining and DNA assay. The level of alkaline phosphatase (ALP) expression and osteocalcin (OCN) deposition in VS442 preserved TEB was also higher than those in the VS55 group since 3days post-rewarm. Both cell viability and osteogenic capability of the VS55 group were found to be declined to a negligible level within 15 days post-rewarm. Furthermore, it was observed that extending the preservation of TEB in VS442 to 3 months did not render any significant effect on its survival and osteogenic potential. Thus, the newly developed VS442 vitreous solution was demonstrated to be more efficient in maintaining cellular viability and osteogenic function for vitreous cryopreservation of TEB over VS55.

Effect of HPV Infection on the Occurrence and Development of Laryngeal Cancer: A Review.

Laryngeal cancer has the second highest incidence of head and neck malignant tumors worldwide. In recent years, studies have shown that human papillomavirus (HPV) infection may be a high-risk factor for laryngeal cancer and closely related to the development and prognosis of laryngeal cancer. The mechanism of the occurrence and development of laryngeal cancer caused by HPV infection needs investigation, as does a rapid and effective HPV detection method for effectively preventing the occurrence of laryngeal cancer and controlling its development. Many studies have explored the relation between HPV infection and laryngeal cancer. Here we review the research progress in investigating HPV infection in terms of DNA, mRNA and protein levels in the occurrence and development of laryngeal cancer and routine HPV detection methods.

Astragali radix total flavonoid synergizes cisplatin to inhibit proliferation and enhances the chemosensitivity of laryngeal squamous cell carcinoma.

Laryngeal squamous cell carcinoma (LSCC) is the most common head and neck cancer. Astragali radix extracts play crucial roles in the regulation of cancer progression. However, the role of Astragali radix extracts in LSCC and the related mechanisms remains unclear. Here, we evaluated the inhibitory effects of the combined use of Astragali radix total flavonoid (TFA) and cisplatin (CDDP) on an LSCC mouse model by pharmacodynamics. Ultra-high-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) was employed to define the prototype of TFA in vivo. The potential drug targets were identified through the integrative analysis of LSCC microarrays, RNA sequencing data and the main bioactive component of TFA. Furthermore, a protein-protein interaction network, compound-target network and target-pathway network were constructed based on the prototype and potential drug targets to identify the main targets and pathways. Animal experiments showed that TFA has significant synergistic antitumor activity with cisplatin and attenuates the nephrotoxicity caused by CDDP chemotherapy, improving the survival of LSCC-bearing mice. Using UPLC-MS/MS, we identified 8 constituents of TFA in experimental mice serum: formononetin, ononin, calycosin, calycosin-7-O-ß-D-glucoside, 7,2'-dihydroxy-3',4'-dimethoxyisoflavan, 7,2'-dihydroxy-3',4'-dimethoxyisoflavaneglucoside, 3-hydroxy-9,10-dimethoxypterocarpan and 9,10-dimethoxyptercarpan-3-O-ß-d-glucoside. Integrative analysis predicted 19 target genes for TFA constituents, and the target genes were mainly involved in the EGFR-related cancer signaling, metabolism and oxidative stress. Collectively, these findings highlight the role of TFA in the regulation of LSCC and provide potential targets for a high-efficiency and low-toxicity therapeutic strategy of LSCC.

Incidents of Mandibular Distraction Osteogenesis for Hemifacial Microsomia.

BACKGROUND: This study focused mainly on the safety and unexpected incidents of mandibular distraction osteogenesis in treating patients with hemifacial microsomia. METHODS: Records of 71 patients with hemifacial microsomia treated by mandibular distraction osteogenesis from February of 2010 to March of 2015 were examined in this retrospective study. The modified mandibular osteotomy was conducted under the assistance of three-dimensional reconstruction, computer-aided design, and rapid prototyping technique. Distraction was conducted 4 to 7 days postoperatively at a frequency of 1 mm/day; moreover, the distractor was kept in place for 4 to 13 months after the first operation before it was removed. The scope of distraction ranged from 20 to 40 mm. All incidents encountered during and after the mandibular distraction process were documented in the medical records of patients. The patients were followed up for an average of 34.4 months after the second-stage operation. RESULTS: The overall rate of incidents was 36.6 percent. Of them, minor incidents, which could be resolved with or without noninvasive therapy, were observed in 18.3 percent of all procedures in this series. Meanwhile, the rate of moderate incidents necessitating invasive therapy was reported to be 12.7 percent, whereas that of major incidents that could not be resolved with invasive therapy was 5.6 percent. CONCLUSIONS: Mandibular distraction osteogenesis is a widely used procedure for treating patients with hemifacial microsomia. It is extremely important to be fully aware of a variety of incidents occurring during and after the surgical procedure to minimize the frequency of occurrence of such incidents. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.