Treacher Collins Syndrome: A Systematic Review of Evidence-Based Treatment and Recommendations

Optimal Diagnostic and Treatment Practices for Facial Dysostosis Syndromes: A Clinical Consensus Statement Among European Experts

Facial dysostosis syndromes (FDS) are rare congenital conditions impacting facial development, often leading to diverse craniofacial abnormalities. This study addresses the scarcity of evidence on these syndromes about optimal diagnostic and treatment practices. To overcome this scarcity, European experts from ERN CRANIO collaborated to develop a clinical consensus statement through the Delphi consensus method. A systematic search of Embase, MEDLINE/PubMed, Cochrane, and Web of Science databases was conducted until February 2023. The quality of evidence was evaluated using various tools depending on the study design. Statements were subsequently formed based on literature and expert opinion, followed by a Delphi process with expert health care providers and patient representatives. In total, 92 experts from various specialties and three patient representatives were involved in the Delphi process. Over 3 voting rounds, consensus was achieved on 92 (46.9%), 58 (59.2%), and 19 (70.4%) statements, respectively. These statements cover the topics of general care; craniofacial reconstruction; the eyes and lacrimal system; upper airway management; genetics; hearing; speech; growth, feeding, and swallowing; dental treatment and orthodontics; extracranial anomalies; and psychology and cognition. The current clinical consensus statement provides valuable insights into optimal diagnostic and treatment practices and identifies key research opportunities for FDS. This consensus statement represents a significant advancement in FDS care, underlining the commitment of health care professionals to improve the understanding and management of these rare syndromes in Europe.

Is There a Role for Comfort Care in Neonates With Severe Craniofacial Anomalies? Case Report and Review of Quality-of-Life Literature

This article aims to determine how quality of life (QoL) is defined and assessed in cases of severe craniofacial anomalies, as well as the impact such considerations may have on the treatment of a neonate with these conditions with respect to palliative neonatal care. Our literature review found insufficient evidence to suggest that craniofacial anomalies result in consistently poor QoL. Based on these findings and in line with the current acceptable standards for the ethical care of neonates, with the exception of rare cases, resuscitative efforts should always be performed on patients with isolated craniofacial anomalies, as demonstrated in the management of this reported patient.

Reconstruction of the orbitozygomatic framework: State of the art and perspectives

The reconstruction of the whole orbitozygomatic framework (OZF) is complex and can be encountered in cases of congenital midface deformity, after tumor ablative surgery and in severe facial trauma. Nowadays, surgeon has a wide range of available techniques that have continually grown over the past years, optimizing the surgical management and the aesthetical outcomes. Among them, the autologous bone graft (ABG) remains one of the most suitable options : ABG is easy to harvest and has optimal biological properties for bone healing. It can be tailored to the patient anatomy thanks to the recent advances in computer-assisted surgery. However, substantial drawbacks remain such as the early resorption of the non-vascularized graft, the need of a donor site and its potential morbidity. Alloplastic reconstruction is another option that can resolve both the resorption issue and the donor site morbidity. Moreover, the 3D-printing technologies also allows the manufacturing of patient specific implants. However, alloplastic materials have a variable success, especially due to the high risk of infection or exposure. Consequently, regenerative medicine is a promising field that aims to find a procedure without the disadvantages of ABG or alloplastic based reconstructions, but displaying similar or even higher success rate. Indeed, recent tissue engineering strategies have demonstrated encouraging results for bone regeneration using natural or synthetic biomaterials, patient cells and synthetic bioactive substances. The objective of this review is to present the etiologies of OZF defect, the available reconstruction procedures as well as the current state of the research.

Severity of Mandibular Dysmorphology in Treacher Collins Syndrome for Stratification of Perioperative Airway Risk

BACKGROUND

Patients with Treacher Collins syndrome (TCS) and attendant airway dysmorphology may be predisposed to airway complications in the perioperative period. However, limited data correlates severity of mandibular hypoplasia and airway status. This study aims to improve risk stratification for perioperative airway insufficiency in TCS by using a previously proposed mandibular severity index.

METHODS

Patient demographics, perioperative airway status, difficulty of intubation, and Cormack Lehane grade were collected and compared using a TCS mandibular hypoplasia severity grading scale in patients with TCS treated between 2000 and 2022.

RESULTS

Twenty-six patients underwent 222 procedures with institutional mandibular severity gradings as follows: 23% Grade I, 31% Grade II, 39% Grade III, 8% Grade IV. Our severity index was associated with intubation difficulty ( P <0.001) and difficult airway status ( P <0.001), with 72% of difficult airways found in grade III and grade IV patients. Mandibular retrusion and ramal hypoplasia subscores were positively correlated with measures of airway severity ( P <0.001), whereas the gonial angle was negatively correlated ( P <0.001). Age was negatively correlated with difficult visualization for endotracheal intubation ( P =0.02) but had no association with difficult airway status ( P =0.2).

CONCLUSIONS

This study found a positive correlation between severity of maxillomandibular dysmorphology and perioperative airway difficulty in TCS patients. Our findings suggest that severely affected patients require heightened vigilance throughout life, as difficult airways may not completely resolve with aging. Given the risk of morbidity and mortality associated with airway complications, proper identification and preparation for challenging airways is critical for TCS patients.

The etiology, clinical features, and treatment options of hemifacial microsomia

The second most frequent craniomaxillofacial congenital deformity is hemifacial microsomia (HFM). Patients often accompany short mandible, ear dysplasia, facial nerve, and soft tissue dysplasia. The etiology of HFM is not fully understood. To organize the possible up-to-date information on the etiology, craniofacial phenotypes, and therapeutic alternatives in order to fully comprehend the HFM. Reviewing the potential causes, exploring the clinical features of HFM and summarizing the available treatment options. Vascular malformation, Meckel's cartilage abnormalities, and cranial neural crest cells (CNCCs) abnormalities are three potential etiology hypotheses. The commonly used clinical classification for HFM is OMENS, OMENS-plus, and SAT. Other craniofacial anomalies, like dental defects, and zygomatic deformities, are still not precisely documented in the classification. Patients with moderate phenotypes may not need any treatment from infancy through adulthood. However, patients with severe HFM require to undergo multiple surgeries to address facial asymmetries, such as mandibular distraction osteogenesis (MDO), autologous costochondral rib graft (CCG), orthodontic and orthognathic treatment, and facial soft tissue reconstruction. It is anticipated that etiology research will examine the pathogenic mechanism of HFM. A precise treatment for HFM may be possible with thoroughly documented phenotypes and a pathogenic diagnosis.

Hospitalizations from Birth to 28 Years in a Population Cohort of Individuals Born with Five Rare Craniofacial Anomalies in Western Australia

OBJECTIVE

To describe trends, age-specific patterns, and factors influencing hospitalizations for 5 rare craniofacial anomalies (CFAs).

METHODS

Data on livebirths (1983-2010; n = 721 019) including rare CFA (craniofacial microsomia, mandibulofacial dysostosis, Pierre Robin sequence, Van der Woude syndrome, and frontonasal dysplasia), episodes of death, and demographic and perinatal factors were identified from the Western Australian Register of Developmental Anomalies, Death Registrations and Midwives Notification System. Information on incident craniofacial and noncraniofacial related admissions, length of hospital stay, and intensive care and emergency-related admissions were identified using principal diagnosis and procedural codes were extracted from the Hospital Morbidity Data Collection and linked to other data sources. Associations of hospitalizations by age groups as well as demographic and perinatal factors were expressed as incidence rate ratio (IRR).

RESULTS

The incident hospitalizations were 3 times as high for rare CFA (IRR 3.22-3.72) throughout childhood into adolescence than those without. Children with rare CFA had 3-4 times as many potentially preventable hospitalizations until 18 years of age than those without. Specifically, respiratory infections (IRR 2.13-2.35), ear infections (IRR 7.92-26.28), and oral health-related conditions contributed for most noncraniofacial admissions until the adolescence period. A greater incidence of noncraniofacial related hospitalizations was observed among Indigenous children, births with intrauterine growth restrictions, and families with high socioeconomic disadvantage.

CONCLUSIONS

Throughout childhood, individuals with rare CFA had greater hospital service use, specifically for potentially preventable conditions, than those without. These population-level findings can inform new preventive strategies and early disease management targeted toward reducing preventable hospitalizations.

Orthodontic and Facial Characteristics of Craniofacial Syndromic Children with Obstructive Sleep Apnea

Introduction: Obstructive sleep apnea (OSA) is a disorder in which ventilation becomes disrupted due to a complete or partial upper airway obstruction Altered craniofacial morphology is one of the most important anatomical factors associated with obstructive sleep apnea (OSA). Studies have assessed craniofacial features in the non-syndromic pediatric population. The aim of this study was to analyze the orthodontic and facial characteristic of craniofacial syndromic children referred for polysomnography (PSG) and to assess the correlation with the apnea-hypopnea index (AHI). Methods: In the current cross-sectional study, consecutive syndromic patients referred for PSG were invited to participate. A systematic clinical examination including extra- and intra-oral orthodontic examination was performed by calibrated orthodontists. Standardized frontal and profile photographs with reference points were taken and analyzed using ImageJ^® software to study the craniofacial morphology. PSG data were analyzed for correlation with craniofacial features. STROBE guidelines were strictly adopted during the research presentation. Results: The sample included 52 syndromic patients (50% females, mean age 9.38 ± 3.36 years) diagnosed with 17 different syndromes, of which 24 patients had craniofacial photography analysis carried out. Most of the sample (40%) had severe OSA, while only 5.8% had no OSA. Down's syndrome (DS) was the most common syndrome (40%) followed by Goldenhar syndrome (5%), Pierre Robin Sequence (5%), and other syndromes. The severity of AHI was significantly correlated with decreased midfacial height. increased thyromental angle and cervicomental angle, decreased mandibular angle, and decreased upper facial height. All patients with DS were diagnosed with OSA (57% severe OSA), and their ODI was significantly correlated with increased intercanthal distance. Obesity was not correlated to the severity of AHI for syndromic patients. Conclusions: Decreased midfacial height and obtuse thyromental angle were correlated with increased AHI for syndromic patients. Increased intercanthal distance of DS patients could be a major predictor of OSA severity. Obesity does not seem to play a major role in the severity of OSA for syndromic patients. Further studies with larger samples are necessary to confirm these findings.

Comprehensive Serial Treatment of Treacher Collins Syndrome

OBJECTIVE

To discuss and summarize the comprehensive serial surgical treatment of Treacher Collins syndrome.

MATERIALS AND METHODS

From September 2012 to January 2020, 12 patients with Treacher Collins syndrome were treated by autologous fat graft, mandibular distraction osteogenesis, orbitozygomatic reconstruction with calvarial external lamina, orthognathic surgery combined with postoperative orthodontics, transplantation of upper eyelid orbicularis myocutaneous flap, lateral canthal ligament reduction, and other methods. The authors evaluated the postoperative improvement, summarized experiences, and reviewed literatures about the comprehensive serial treatment of Treacher Collins syndrome.

RESULTS

All patients showed significant improvement in appearance and function, and no complications were found during the follow-up period of 5 months to 3 years.

CONCLUSIONS

The deformities of Treacher Collins syndrome involves multiple craniofacial region, and only by formulating comprehensive serial treatment strategies according to the malformation characteristics of different patients can the best effect be achieved.

A systematic review on Treacher Collins syndrome: Correlation between molecular genetic findings and clinical severity

Treacher Collins syndrome (TCS, OMIM: 154500) is a rare congenital craniofacial disorder that is caused by variants in the genes TCOF1, POLR1D, POLR1C, and POLR1B. Studies on the association between phenotypic variability and their relative variants are very limited. This systematic review summarized the 53 literatures from PubMed and Scopus to explore the potential TCS genotype-phenotype correlations with statistical analysis. Studies reporting both complete molecular genetics and clinical data were included. We identified that the molecular anomaly within TCOF1 (88.71%) accounted for most TCS cases. The only true hot spot for TCOF1 was detected in exon 24, with recurrent c.4369_4373delAAGAA variant is identified. While the hot spot for POLR1D, POLR1C, and POLR1B were identified in exons 3, 8, and 15, respectively. Our result suggested that the higher severity level was likely to be observed in Asian patients harboring TCOF1 variants rather than POLR1. Moreover, common 5-bp deletions tended to have a higher severity degree in comparison to any variants within exon 24 of TCOF1. In summary, this report suggested the relationship between genetic and clinical data in TCS. Our findings could be used as a reference for clinical diagnosis and further biological studies.

Treacher Collins syndrome: A case report and review of literature

Treacher Collins syndrome (TCS) is one of the rare genetic syndromes which is specified by symmetrical craniofacial dysmorphism without growth abnormalities or neurological disorders. The inheritance is usually autosomal dominant but sometimes it is a sporadic mutation. Prenatal diagnosis could be realized by genetic testing of a chorionic villus sample or amniocentesis if one of the parents is affected. At birth, the most common features are downward-sloping palpebral clefts, small badly hemmed and folded ears, and mandibular hypoplasia which could lead to respiratory distress. All of these clinical features exist in our case. Goldenhar syndrome shares with TCS some facial features which are not symmetrical and it is also associated with vertebral abnormalities. Some patients with TCS are exposed to many complications and they require multi-disciplinary medical care. But all of them need psychiatric care to fight social rejection. The aim of our report is to describe the most common features of TCS and similar syndromes. Also, report the involved genetic mutations, some associated complications, and their management.

Characterization of Phenotypes and Treatment Modalities in Patients With Treacher-Collins Syndrome

ABSTRACT

The purpose of this study was to investigate the phenotypes and treatment modalities (Tx-Mod) in patients with Treacher-Collins syndrome (TCS) using a TCS severity index (TSI). The sample consisted of 14 Korean TCS patients treated at the Department of Orthodontics, Seoul National University Dental Hospital during 1998 to 2019. The TSI was calculated by adding the scores from the number of deformity-involved midface structures (eye, ear, zygoma) and the degree of mandibular hypoplasia (Pruzansky-Kaban type, gonial angle, Sella-Nasion-B point angle). The deformity-involved midface structure, degree of mandibular hypoplasia, oral manifestations, dental phenotypes, and Tx-Mod types were investigated using descriptive statistics. The TSI classified the subjects into 2 mild, 6 moderate, and 6 severe cases. The severity of ear and zygoma deformities, degree of condylar hypoplasia (Pruzansky-Kaban type), clockwise-rotated morphology (gonial angle) and retrusive position (Sella-Nasion-B point angle) of the mandible, and frequency of oral/craniofacial cleft, openbite, congenitally missing tooth and impacted tooth showed a tendency of increase from mild to severe TCS cases. After growth observation (78.6%), diverse combinations of Tx-Mods were applied except for functional appliance therapy. Surgical procedures for eye, ear, and zygoma reconstruction were performed on all patients (100%), whereas fixed orthodontic treatment, mandibular distraction osteogenesis, and orthognathic surgery were performed on 50% of patients. Surgical procedure for hearing improvement was the most frequent Tx-Mod (78.6%). The main desires of TCS patients were to obtain the facial esthetics in the midface and to improve hearing function. The TSI might provide a primary data for individualized diagnosis and treatment planning.

Craniofacial and Upper Airway Development in Patients With Treacher Collins Syndrome

ABSTRACT

This study evaluated age-associated morphology changes in the cranial base, facial development, and upper airway of patients with Treacher Collins syndrome (TCS). A total of 33 preoperative computed tomographic images (TCS, n = 14; control, n = 19) were included in the study and divided into three age-related subgroups (2-6 years, 7-18 years, and older than 18 years). Linear, angular cephalometric measurements and upper airway volumes were collected. All measurements were analyzed using ProPlan CMF software (version 3.0; Materialize, Leuven, Belgium). The association between aging and upper airway morphology was analyzed. Compared to control subjects, TCS patients had a smaller cranial base, maxilla, and nose; they also had reduced upper airway volume compared to control subjects. The observed differences were most significant in patients between the ages of 7 and 18 years. This study used computed tomography-based three-dimensional analyses to provide a detailed description of age-related changes that occur in craniofacial measurements and upper airway volumes in children, adolescents, and young adult patients with TCS in China. These data can be used to evaluate individual patients with TCS and to select treatment to improve the growth of the craniofacial region.

Description of Total Population Hospital Admissions for Treacher Collins Syndrome in Australia

OBJECTIVE

To describe patterns and demographic characteristics of total-population hospital admissions with a diagnosis of Treacher Collins syndrome (TCS) in Australia.

DATA SOURCE

Population summary data for inpatient hospitals admissions (public and private) with a principal diagnosis of TCS (ICD10-AM-Q87.04) were obtained from the Australian Institute of Health and Welfare National Hospital Morbidity Database for a 11-year period (2002-2013).

MAIN OUTCOME MEASURES

The primary outcome was hospital separation rate (HSR), calculated by dividing the number of hospital separations by estimated resident population per year. Trends in HSR s adjusted for age and sex were investigated by negative binomial regression presented as annual percent change and the association of rates with age and sex was expressed as incidence rate ratio.

RESULTS

In 244 admissions identified, we observed an increase of 4.55% (95% confidence interval [CI] -1.78, 11.29) in HSR's over the 11-year period. Rates were higher during infancy (1.87 [95% CI 1.42, 2.42]), declining markedly with increasing age. The average length of hospital stay was 6.09 days (95% CI 5.78, 6.40) per episode, but longer for females and infants.

CONCLUSIONS

Findings indicate an increase in hospitalization rates, especially among infants and females which potentially relates to early airway intervention procedures possibly influenced by sex specific-disease severity and phenotypic variability of TCS. Awareness of the TCS phenotype and improved access to genetic testing may support more personalized and efficient care. Total-population administrative data offers a potential to better understand the health burden of rare craniofacial diseases.

Treacher Collins Mandibular Distraction

Treacher Collins syndrome (TCS) is a genetic disorder that presents with a variety of craniofacial deformities. One classic feature of TCS is a steep, counterclockwise rotation of the occlusal plane, and microretrognathia with bony deficiencies in both the body and ramus of the mandible. This morphology commonly necessitates reconstruction by the craniofacial surgeon. This article discusses strategies and considerations for surgically correcting the mandibular deformity associated with TCS using mandibular distraction osteogenesis and other related techniques. The proper implementation of these techniques can yield excellent results that greatly improve quality of life in this challenging patient population.

Counterclockwise Craniofacial Distraction Osteogenesis

Anatomic studies have identified that patients with Treacher Collins syndrome and some cases of bilateral craniofacial microsomia are characterized by multilevel airway obstruction as a result of hypoplasia and clockwise rotation of the maxillomandibular complex. Patients often remain tracheostomy-dependent despite multiple airway surgeries. Counterclockwise craniofacial distraction osteogenesis aims to correct the facial skeletal deformity and expand the upper airway volume by rotating the subcranial complex en bloc around the nasofrontal junction. Early results have demonstrated significant increases in the nasopharyngeal and oropharyngeal airway volumes with successful decannulation in a majority of patients who have undergone this operation.

Treacher Collins syndrome: Orthodontic treatment with mandibular distraction osteogenesis and orthognathic surgery

Interdisciplinary treatment for patients with Treacher Collins syndrome is challenging because of the rarity of the condition and the wide variety of phenotypic expression. A 23-year-old male was diagnosed with Treacher Collins syndrome with a history of severe obstructive sleep apnea. He presented with a Pruzansky-Kaban classification grade I mandible, skeletal type II pattern with a hyperdivergent mandibular plane, severe convex profile, and Class II malocclusion with a missing mandibular incisor. Improvement of facial esthetics was achieved by a combination of orthodontics, mandibular distraction osteogenesis, and 2-jaw maxillomandibular advancement surgery. Presurgical orthodontic treatment involved permanent tooth extraction to relieve severe crowding, and Class III mechanics were employed to increase overjet. Correction of mandibular hypoplasia by increasing ramal height and the mandibular length was done by intraoral mandibular distraction osteogenesis. Counterclockwise rotation of the mandibular plane angle and a Class III occlusion with negative overjet were achieved after mandibular distraction osteogenesis. A postdistraction posterior open bite was maintained with a biteplane during the consolidation period. Subsequently, 2-jaw orthognathic surgery was performed. LeFort I osteotomy was done for maxillary advancement to correct an anterior crossbite, eliminate canting, and reestablish occlusal contact at the mandibular occlusal plane. Bilateral sagittal split ramus osteotomy was done to correct the residual mandibular deviation. A genioplasty was also performed to improve chin projection. Postoperatively, the oropharyngeal airway was enlarged. The patient's facial profile and obstructive sleep apnea problem were improved as a result of advancement and counterclockwise rotation of the maxillomandibular complex.

[Obstructive sleep apnea in microtia children with maxillofacial dysostosis]

Children with microtia are often associated with maxillofacial dysostosis, such as Treacher Collins syndrome, Goldenhar syndrome, and Nager syndrome, and they are prone to suffer from obstructive sleep apnea（OSA）. Obstruction widely occurred in the upper airway is the main mechanism of OSA in these children, and dysplasia of the pharynx and neurodevelopmental abnormalities may also participate. Early diagnosis requires symptom screening and polysomnography. Imaging techniques and endoscopy can be adopted to fully assess the upper airway status to guide further treatment. According to the child's condition and the main obstruction site, treatment methods include maxillofacial deformity correction, continuous positive pressure ventilation and tracheotomy. OSA in microtia children with maxillofacial dysostosis needs to be identified and treated in time to reduce the adverse effects on the growth and development of children.

Extracraniofacial anomalies in Treacher Collins syndrome: A multicentre study of 248 patients

Treacher Collins syndrome (TCS) is a congenital malformation of the craniofacial structures derived from the first and second pharyngeal arches. The craniofacial deformities are well described in the literature. However, little is known about whether there are associated extracraniofacial anomalies. A retrospective study was conducted using data from four craniofacial units. Medical charts were reviewed for the presence and type of extracraniofacial anomalies, as well as age at diagnosis. A possible correlation between the severity of the phenotype and the presence of extracraniofacial anomalies was assessed using the Hayashi classification. A total of 248 patients with TCS were identified; 240 were confirmed to have TCS, of whom 61 (25.4%) were diagnosed with one or more extracraniofacial anomalies. Ninety-five different extracraniofacial anomalies were found; vertebral (n=32) and cardiac (n=13) anomalies were most frequently seen, followed by reproductive system (n=11), central nervous system (n=7), and limb (n=7) anomalies. No correlations between tracts were found. Extracraniofacial anomalies were more prevalent in these patients with TCS compared to the general population (25.4% vs 0.001-2%, respectively). Furthermore, a positive trend was seen between the severity of the syndrome and the presence of extracraniofacial anomalies. A full clinical examination should be performed on any new TCS patient to detect any extracraniofacial anomalies on first encounter with the craniofacial team.

Alloplastic Temporomandibular Joint Reconstruction in Congenital Craniofacial Deformities

ABSTRACT

Temporomandibular joint (TMJ) reconstruction with alloplastic prosthesis is a commonly performed procedure, which can be used as a treatment for improving pathologic conditions affecting the TMJ. Depending of the severity of the condition, the patient's ability to eat can be impaired, which in turn can affect their quality of life. Several syndromes can affect the patient's facial features, and some of those also affect TMJ's. Use of alloplastic prosthesis in TMJ's affecting syndromes, by means of correcting TMJ conditions and mandibular deformities, is still rather uncommon. Purpose of our study is to review the use TMJ total prosthesis as a treatment modality for correcting TMJ conditions and the reconstruction of mandibular deformities in congenital syndromes affecting the facial features. This study consists of a retrospective cohort of patients treated with TMJ reconstruction with alloplastic prosthesis at the Helsinki University Hospital during the past decade. All subjects with congenital syndrome who underwent TMJ reconstruction were included the study. The cohort consisted of seven patients and ten joints treated. Temporomandibular joints affecting syndromes were Goldenhar syndrome, hemifacial macrosomia, Nager syndrome, and Treacher-Collins syndrome. The majority of the patients have had several previous operative treatments on the facial skeleton during their childhood, which in turn probably affected and compromised the TMJ surgery outcome. Mouth opening was sufficiently achieved as average maximal opening was 34 mm (range 24-42 mm) postoperatively. Temporomandibular joint reconstruction with alloplastic prosthesis can offer new tools and approaches for treatment of facial deformities in syndromes with craniofacial abnormalities. Impaired jaw functions and asymmetry can be addressed with the use of alloplastic prostheses, achieving sufficient mouth opening and restoring the symmetry of the lower facial skeleton.

[Three-dimensional measurement analysis of midface morphology in Treacher Collins syndromes]

Objective

To three-dimensionally calculate the craniofacial parameters of midface of patients with Treacher Collins syndrome (TCS) in China, in order to understand the changes in the spatial position relationship between the various anatomical structures of the midface.

Methods

CT imaging data of TCS patients and age- and gender-matched normal populations between January 2013 and July 2020 was retrospectively analyzed. A total of 33 cases met the selection criteria for inclusion in the study, including 14 cases in the TCS group and 19 cases in the control group. ProPlan CMF 3.0 software was used to perform three-dimensional digital reconstruction of the craniofacial bone, measure the anatomical parameters of the midface, and analyze its morphological structure; at the same time perform three-dimensional digital reconstruction of the upper airway for morphological analysis (measure upper airway volume).

Results

CT images analysis revealed that all 14 patients with TCS presented the typical features with downward slanting of the palpebral fissures and different degrees of zygomatico-orbital complex dysplasia. Cephalometric and morphological analysis of the midface revealed that, multiple transverse diameters of the midface of TCS patients were significantly decreased when compared with the control group ( P<0.05), such as the width of the maxillary base, the length of the maxillary complex, and some distances related to the nasal morphology; but the distance between bilateral orbitales increased in TCS group ( P<0.05). Several anteroposterior distances in TCS group were decreased significantly when compared to control group and the distance between the skull base point and the posterior nasal spine was the most shortened ( P<0.05). But there was no significant difference of the distance between nasion and anterior nasal spine, which represented anterior midface height, between groups ( P>0.05). The skull base angle and SNB angle (the angle between the sella point-nose root point-inferior alveolar seat point) of the TCS group both decreased when compared with the control group ( P<0.05), but there was no significant difference in SNA angle (the angle between the sella point-nose root point-upper alveolar seat point) between the two groups ( P>0.05). The total volume of the upper airway was (24 621.07±8 476.63) mm ³ in the TCS group, which was significantly lower than that of the control group [(32 864.21±13 148.74) mm ³] ( t=2.185, P=0.037).

Conclusion

The transverse distances, anteroposterior distances, and multiple craniofacial angles measurement of TCS patients were significantly decreased when compared to the control group, presented with different degrees of zygomatico-orbital complex dysplasia, nasal and maxillary dysplasia, but there was no obvious restriction in face height development. Reduced internal diameters of the upper airway maybe responsible for the decreased upper airway volume of patients with TCS.

Functional outcomes in patients with facial dysostosis and severe upper airway obstruction

An increased risk of upper airway obstruction (UAO) is seen in up to 95% of patients with facial dysostosis. Secondary to respiratory problems are feeding difficulties and increased nutritional requirements. Little has been described regarding these outcomes in this patient population. Hence, a retrospective cohort study was performed to gather data on functional outcomes. Eighteen patients with facial dysostosis and severe UAO were included. The median follow-up time was 3.42 years. A tracheostomy tube was placed in 13 patients, of whom 10 subsequently underwent mandibular distraction. Three of the five patients without a tracheostomy underwent mandibular distraction as the primary surgical treatment; the remaining two patients were treated conservatively with oxygen supplementation. At presentation, 13 patients had feeding difficulties. Overall malnutrition was present in 16 patients during follow-up. At the end of follow-up, severe UAO was present in 12 patients, feeding difficulties in seven patients, and malnutrition in four patients, while two patients died. In conclusion, patients with facial dysostosis have a high prevalence of severe UAO, feeding difficulties, and malnutrition. Importantly, mandibular distraction has limited success in treating severe UAO in these patients. Close follow-up by a specialized craniofacial team is of paramount importance to manage the long-term consequences.

Imaging of the Fetal Zygomatic Bone: A Key Role in Prenatal Diagnosis of First Branchial Arch Syndrome

OBJECTIVES

First arch syndromes are congenital defects caused by failure of neural crest cells to migrate into the first branchial arch. First arch syndrome is classified into 2 main clinical manifestations: Treacher Collins syndrome, characterized by bilateral underdevelopment of the zygomatic bones; and Pierre Robin sequence. The aim of this study was to describe the feasibility of visualization of the fetal zygomatic bone and assess its application in cases referred for features suggestive of first arch syndrome.

METHODS

A prospective cohort study was conducted. The feasibility of visualization of the zygomatic bone was performed in 50 sequential fetuses with a normal anatomic scan between 12 and 24 weeks' gestation using 3-dimensional sonography. Following this, cases referred for targeted scans for suspected first branchial arch syndrome were assessed for the presence or absence of the zygomatic bones.

RESULTS

Visualization of the fetal zygomatic bone was feasible in all low-risk cases. Cases referred for targeted scans included 11 isolated cases of micrognathia or retrognathia, 3 cases of microtia, and 3 cases of auricular or facial vestiges. Within this group, the zygomatic bones were visualized in all but 2 cases. No associated extrafacial malformations were detected; therefore, this phenotype was consistent with Treacher Collins syndrome.

CONCLUSIONS

Prenatal imaging of the zygomatic bones offers a clinically based sonographic approach to cases referred for features suggestive of first arch syndrome and enables differentiation between the 2 main clinical manifestations: Treacher Collins syndrome and Pierre Robin sequence.

Ribosomopathies: New Therapeutic Perspectives

Ribosomopathies are a group of rare diseases in which genetic mutations cause defects in either ribosome biogenesis or function, given specific phenotypes. Ribosomal proteins, and multiple other factors that are necessary for ribosome biogenesis (rRNA processing, assembly of subunits, export to cytoplasm), can be affected in ribosomopathies. Despite the need for ribosomes in all cell types, these diseases result mainly in tissue-specific impairments. Depending on the type of ribosomopathy and its pathogenicity, there are many potential therapeutic targets. The present manuscript will review our knowledge of ribosomopathies, discuss current treatments, and introduce the new therapeutic perspectives based on recent research. Diamond–Blackfan anemia, currently treated with blood transfusion prior to steroids, could be managed with a range of new compounds, acting mainly on anemia, such as L-leucine. Treacher Collins syndrome could be managed by various treatments, but it has recently been shown that proteasomal inhibition by MG132 or Bortezomib may improve cranial skeleton malformations. Developmental defects resulting from ribosomopathies could be also treated pharmacologically after birth. It might thus be possible to treat certain ribosomopathies without using multiple treatments such as surgery and transplants. Ribosomopathies remain an open field in the search for new therapeutic approaches based on our recent understanding of the role of ribosomes and progress in gene therapy for curing genetic disorders.

Mutation analysis of TCOF1 gene in Chinese Treacher Collins syndrome patients

Background

Treacher Collins syndrome (TCS) is a rare autosomal dominant or recessive disorder, that involves unique bilateral craniofacial malformations. The phenotypes of TCS are extremely diverse. Interventional surgery can improve hearing loss and facial deformity in TCS patients.

Method

We recruited seven TCS families. Variant screening in probands was performed by targeted next‐generation sequencing (NGS). The variants identified were confirmed by Sanger sequencing. The pathogenicity of all the mutations was evaluated using the guidelines of the American College of Medical Genetics and Genomics (ACMG) and InterVar software.

Results

Three frameshift variants, two nonsense variants, one missense variant, and one splicing variant of TCOF1 were identified in the seven TCS probands. Five variants including c.1393C > T, c.4111 + 5G>C, c.1142delC, c.2285_2286delCT, and c.1719delG had not been previously reported. Furthermore, we report the c.149A > G variant for the first time in a Chinese TCS patient. We provided prenatal diagnosis for family 4. Proband 7 chose interventional surgery.

Conclusion

We identified five novel variants in TCOF1 in Chinese patients with TCS, which expands the mutation spectrum of TCOF1 in TCS. Bone conduction hearing rehabilitation can improve hearing for TCS patients and prenatal diagnosis can provide fertility guidance for TCS families.

Prevention methods for Treacher Collins syndrome: A systematic review

OBJECTIVES

Treacher Collins syndrome (TCS) is a severe congenital mandibulofacial dysostosis that occurs one in every 50,000 births. The main clinical treatment of this rare disorder is reconstruction surgery. However, the high invasion, low security and long period of surgical intervention make it essential to explore prevention methods to decrease morbidity. The authors' aim is to summarize the prevention methods based on known mechanisms of TCS.

METHODS

A systematic review was conducted through an electronic search of PubMed, EMBASE and Web of Science databases through November 2019 using the following items: 'Treacher Collins syndrome OR TCS OR Franceschetti-Zwahlein-Klein syndrome OR Berry syndrome', 'gene therapy OR prevention'. Four causative gene names were also used. Articles which published in English language and explored the prevention methods for TCS were included and data concerning animal model, intervention, phenotype, conclusion were gathered.

RESULTS

Sixty-five studies were reviewed in total, and seven articles were included in this systematic review. Four articles used prevention methods related to the inhibition of p53, and three related to preclusion of oxidative stress-induced DNA damage.

CONCLUSIONS

This article provides a comprehensive review of the prevention methods for craniofacial abnormalities characteristic of TCS based on known pathogenesis in the current literatures. The craniofacial phenotype could be rescued through several treatment methods experimentally such as p53 inhibition and antioxidant administration.

[Progress of diagnosis and treatment of upper respiratory obstruction in patients with Treacher Collins syndrome]

Objective

To summarize the progress of diagnosis and treatment of upper respiratory obstruction in patients with Treacher Collins syndrome (TCS).

Methods

The domestic and abroad literature about the diagnosis and treatment of upper respiratory obstruction in patients with TCS was extensively reviewed and analyzed.

Results

TCS is an autosomal-dominant craniofacial developmental syndrome. It is often accompanied by midface and/or mandibular hypoplasia, soft tissue hypertrophy, and other respiratory tissue developmental abnormalities, which can lead to different degrees of upper respiratory obstruction symptoms. Respiratory obstruction in patients with TCS is affected by many factors, and the obstructive degree are different. Early detection of the causes and obstructive sites and adopted targeted treatments can relieve the symptoms of respiratory obstruction and avoid severe complications.

Conclusion

Due to the low incidence of TCS, there is still a lack of high-quality research evidence to guide clinical treatment. Large-scale and prospective clinical studies are needed to provide new ideas for the treatment and prevention of upper respiratory obstruction.

Three-Dimensional Upper Airway Assessment in Treacher Collins Syndrome

Objectives:

The purpose of this investigation was to assess the pharyngeal dimensions and the craniofacial morphology of individuals with Treacher Collins syndrome (TCS) when compared to vertical skeletal class II individuals. It is our hypothesis that the upper airways of individuals with TCS are reduced in view of the skeletal pattern and the maxillomandibular dysmorphologies.

Materials and Methods:

Cone-beam computed tomography scans of 26 individuals had the pharyngeal volume (V) and minimal cross-sectional area (mCSA) evaluated. Study group (TCS) was formed by 13 scans of patients with TCS (7 males and 6 females; 20.2 ± 4.7 years). Control group (CG) assembled 13 scans of nonaffected individuals with the same type of skeletal pattern (2 males and 11 females; 26.6 ± 5.4 years). Cephalometric data of maxillomandibular position, maxillomandibular dimensions, and growth pattern were assessed. Statistical analysis ( P ≤ .05) included Student t test and Pearson correlation coefficient.

Results:

Although reduced, pharyngeal V and mCSA of TCS were not statistically different from the CG. On both groups, mCSA was mostly at the oropharyngeal level. Individuals with TCS presented retrognathic chin, reduced maxillomandibular dimensions, and increased clockwise rotation of the palatal plane. Maxillary and mandibular lengths were correlated with pharyngeal V and mCSA.

Conclusions:

The pharyngeal dimensions of individuals with TCS are impacted by the micrognathia and retrognathia. In association with the skeletal pattern, the reduction of the airways, although not statistically significant, may explain the increased prevalence of airways disorder in this syndrome.

Surgical management of the Tessier 7 cleft: A review and presentation of 5 cases

INTRODUCTION

Several variations on the surgical technique for macrostomia repair have been described in the literature. There has been controversy regarding the preferred method for commissuroplasty and skin closure for optimal functional and aesthetic results. The aim of this study is to present these techniques and the most described methods up to date.Further, five patients operated with a combination of techniques are presented.

MATERIAL AND METHODS

PRISMA guidelines were followed for literature review.Five consecutive patients with unilateral macrostomia operated during a period of one and a half years at our craniofacial department were included in this study.

RESULTS

31 studies on macrostomia repair were obtained. The layered closure technique is widely described with several variations on closure of the inner mucosa, orbicularis muscle, commissure and skin. The inner mucosal layer is in most cases sutured with a straight line closure technique. The muscle is most often duplicated and sutured with upper branches overlapping lower branches. The skin is in most cases sutured with either a z- or a w-plasty with variations.The five presented patients all had satisfactory functional and aesthetic results at follow-up.

CONCLUSION

Many variations of surgical techniques for macrostomia repair have been presented in the past. We believe that each case of macrostomia needs to be assessed with a tailored surgical plan in order to create the best results. A combination of different techniques with Bütow and Botha's and Kaplan's technique as a starting point, is believed to give satisfactory functional and aesthetic results.

TCOF1 pathogenic variants identified by Whole-exome sequencing in Chinese Treacher Collins syndrome families and hearing rehabilitation effect

Background

Treacher Collins syndrome (TCS, OMIM 154500) is an autosomal disorder of craniofacial development with an incidence rate of 1/50,000 live births. Although TCOF1, POLR1D, and POLR1C, have been identified as the pathogenic genes for about 90% TCS patients, the pathogenic variants of about 8–11% cases remain unknown. The object of this study is to describe the molecular basis of 14 clinically diagnosed TCS patients from four families using Whole-exome sequencing (WES) followed by Sanger sequencing confirmation, and to analyze the effect of bone conduction hearing rehabilitation in TCS patients with bilateral conductive hearing loss.

Results

Four previously unreported heterozygous pathogenic variants (c.3047-2A > G, c.2478 + 5G > A, c.489delC, c.648delC) were identified in the TCOF1 gene, one in each of the four families. Sanger sequencing in family members confirmed co-segregation of the identified TCOF1 variants with the phenotype. The mean pure-tone threshold improvements measured 3 months after hearing intervention were 28.8 dB for soft-band BAHA, 36.6 ± 2.0 dB for Ponto implantation, and 27.5 dB SPL for Bonebridge implantation. The mean speech discrimination improvements measured 3 months after hearing intervention in a sound field with a presentation level of 65 dB SPL were 44%, 51.25 ± 5.06, and 58%, respectively. All six patients undergoing hearing rehabilitation in this study got a satisfied hearing improvement.

Conclusions

WES combined with Sanger sequencing enables the molecular diagnosis of TCS and may detect other unknown causative genes. Bone conduction hearing rehabilitation may be an optimal option for TCS patients with bilateral conductive hearing loss.

Urgent Complex Intraoperative Reintubation in a Known Difficult Airway After Endotracheal Tube Damage: A Case Report

Treacher Collins syndrome is an inherited disorder resulting in maldevelopment of the first and second branchial arches. Patients have complex orofacial anatomy often requiring airway interventions from birth. A 17-year-old boy with Treacher Collins syndrome and history of difficult ventilation and intubation presented for elective maxillofacial reconstruction. After uneventful awake nasal fiberoptic intubation, the nasotracheal tube was damaged intraoperatively. Due to the patient's unique anatomy, a fiberoptic bronchoscope and ventilating exchange catheter were utilized together to facilitate a nasotracheal tube exchange. This case demonstrates the utilization of a combination of advanced airway techniques in an urgent perioperative setting.

Proteasomal inhibition attenuates craniofacial malformations in a zebrafish model of Treacher Collins Syndrome

Treacher Collins Syndrome (TCS) is a congenital disease characterized by defects in the craniofacial skeleton and absence of mental alterations. Recently we modelled TCS in zebrafish (Danio rerio) embryos through the microinjection of Morpholino® oligonucleotides blocking the translation of the ortholog of the main causative gene (TCOF1). We showed that Cnbp, a key cytoprotective protein involved in normal rostral head development, was detected in lower levels (without changes in its mRNA expression) in TCS-like embryos. As previous reports suggested that Cnbp is degraded through the proteasomal pathway, we tested whether proteasome inhibitors (MG132 and Bortezomib (Velcade®, Millennium laboratories)) were able to ameliorate cranial skeleton malformations in TCS. Here we show that treatment with both proteasome inhibitors produced a robust craniofacial cartilage phenotype recovery. This recovery seems to be consequence of a decreased degradation of Cnbp in TCS-like embryos. Critical TCS manifestations, such as neuroepithelial cell death and cell redox imbalance were attenuated. Thus, proteasome inhibitors may offer an opportunity for TCS molecular and phenotypic manifestation's prevention. Although further development of new safe inhibitors compatible with administration during pregnancy is required, our results encourage this therapeutic approach.

Counterclockwise Craniofacial Distraction Osteogenesis for Tracheostomy-Dependent Children with Treacher Collins Syndrome

BACKGROUND

The craniofacial rotation deformity in Treacher Collins syndrome results in airway compression that is not addressed by isolated mandibular distraction osteogenesis. Our purpose is to present a surgical technique-counterclockwise craniofacial distraction osteogenesis-that improves airway morphology and occlusal rotation in tracheostomy-dependent patients with this condition.

METHODS

All patients underwent subcranial Le Fort II osteotomies with simultaneous mandibular osteotomies, followed by coordinated maxillomandibular distraction with counterclockwise rotation. We reviewed pretreatment, posttreatment, and end-treatment cephalograms. Airway changes were assessed using polysomnography, sleep endoscopy, and direct laryngoscopy. Bivariate statistics were computed to compare pretreatment and posttreatment measures.

RESULTS

Five subjects (age range, 4.5 to 12.1 years) underwent this new procedure; three had previously undergone mandibular distraction. The average palatal plane rotation was 17 degrees, the effective mandible length increase was 18 mm, and the facial plane relative to skull base rotation was 14 degrees. There was a symmetric 30 percent relapse of rotation with maintained occlusion in the first 9 months of follow-up that then stabilized. Four patients were successfully decannulated following counterclockwise craniofacial distraction osteogenesis following polysomnography. Sleep endoscopy available on two patients demonstrated resolution of the upper airway obstruction.

CONCLUSIONS

Counterclockwise craniofacial distraction osteogenesis provided greater palatal rotation than previous techniques. The resulting improvement in airway anatomy allowed for decannulation in four of five tracheotomized patients. Stability of the counterclockwise rotation is comparable to that of related orthognathic operations, despite substantially greater magnitude.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Microtia and Related Facial Anomalies

Infants may be born with external ear deformities or malformations that can present a diagnostic clue to an affiliated syndrome while also presenting the possibility of surgical intervention. Microtia is a malformation of the ear that is associated with other craniofacial or systemic anomalies in 50% of cases. Surgical correction of microtia and associated facial anomalies is complex and must be integrated thoughtfully into the overall care plan for children with complex medical needs. Familiarity with types of ear and facial anomalies and their association with more global concerns can allow perinatal practitioners to better serve their patients.

Oculoauriculovertebral spectrum and maxillary sinus volumes : CT-based comparative evaluation

OBJECTIVES

To evaluate, by comparing maxillary sinus volumes, how asymmetries related to oculoauriculovertebral spectrum (OAVS) affect upper-jaw development.

METHODS

From pre-existing multislice spiral computed tomography (MSCT) datasets, we selected 20 cases of 11 female and 9 male patients aged 6.1-24 years who were clinically and radiographically symmetrical (group 1) plus 20 cases of 8 female and 12 male patients aged 5.7-23.9 years who had OAVS (group 2). After three-dimensional reconstruction of the datasets, the volumes of the left and right maxillary sinuses were calculated and compared based on patient groups and based on the sides affected or unaffected by OAVS. To this end, the OAVS patients were subdivided into a group in whom both external acoustic pores were radiographically present (group 2a) and a group in whom the pore on the affected side was congenitally missing (group 2b).

RESULTS

Intrarater reliability was very high (0.997). Significantly larger volumes of the maxillary sinuses, amounting to a mean of 13.4 ml, were observed in the control group than in the asymmetric OAVS groups where the volumes averaged 9.8 ml or 10.3 ml, respectively (p = 0.03). No statistically significant differences in sinus volumes were found between the two OAVS groups (p = 0.557) and between the sides affected or unaffected by the OAVS (p = 0.8311 in group 2a and 0.4961 in group 2b).

CONCLUSIONS

Overall, we found the volumes of both maxillary sinuses to be somewhat smaller in the asymmetric patients than in the symmetric control group. This might indicate that OAVS was associated with a mild generalized hypoplasia of the maxilla, but significantly different sinus volumes were not seen between the affected and unaffected sides.

Assessing Psychological Adjustment to Congenital Craniofacial Anomalies: An Illustration of Methodological Challenges

Background:

Recognition of the challenges inherent in psychology research related to cleft lip and/or palate (CL/P) and other craniofacial anomalies (CFAs) is far from novel; yet these challenges continue to limit progress within the field. The aim of the present article was to illustrate these challenges by utilizing data extracted from 2 recent literature reviews pertaining to psychological adjustment within CL/P and CFA research.

Design:

Data relating to 148 CL/P and 41 CFA studies were extracted, summarized, and compared, using percentages, figures, and χ2 calculations.

Results:

Comparable patterns were observed in both populations in relation to small sample sizes, wide age ranges, a reliance on data collection from single sites, and limited global coverage. Similarly, only one-third of all studies had used a comparison group, 42% of studies did not include the patient perspective, and fewer than 10% of studies had collected data longitudinally. Qualitative research was lacking across both populations, but particularly in relation to CFA. A higher proportion of CFA studies utilized validated measures and were less likely to exclude patients with additional anomalies. CFA studies most frequently focused on behavior and overall quality of life, while CL/P studies tended to investigate emotional well-being and social experiences.

Conclusions:

Findings illustrate the variability in research approaches, sampling, measurement, and analysis across both populations. There is a pressing need to address key methodological issues within craniofacial research and to examine the possible similarities and condition-specific differences between CL/P and other congenital craniofacial anomalies.

Patient-Reported Quality of Life in the Highest Functioning Patients With Treacher Collins Syndrome

BACKGROUND

Treacher Collins syndrome has a wide variation of clinical presentation, including airway obstruction and hearing loss. The objective of this study was to assess patient-rated quality of life in Treacher Collins syndrome, who received multidisciplinary treatment at a specialized craniofacial hospital, and to compare their quality of life with a control sample.

METHODS

Treacher Collins patients under treatment in a multidisciplinary setting were assessed with the World Health Organization Quality of Life (WHOQOL-100) questionnaire. The Siviero scale was used to classify quality of life as unsatisfactory (scores below 25), intermediate (scores between 25 and 75), and satisfactory (scores above 75). Quality of life comparison between Treacher Collins patients and 2342 unaffected individuals from a previous database was performed using the analysis of variance test. Differences were considered significant at P < 0.05.

RESULTS

Treacher Collins patients demonstrated an overall intermediate and satisfactory (score >60%) quality of life in almost all WHOQOL-100 facets and domains. The comparison of the scores between unaffected individuals and Treacher Collins patients demonstrated a significant difference (P < 0.05) in the environment domain.

CONCLUSION

The highest functioning Treacher Collins syndrome patients under multidisciplinary treatment presented intermediate and satisfactory quality of life, consistent with quality of life scores of unaffected controls. In the environment domain, Treacher Collins patients presented even higher scores of quality of life than the control group.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Evaluation and management of syndromic congenital hearing loss

PURPOSE OF REVIEW

The purpose of this review is to review the evaluation and management of children with syndromic hearing loss. Specific syndromes and the impact of those syndromes on managing hearing loss will be discussed.

RECENT FINDINGS

Improved molecular testing has increased the ability to identify syndromes-associated hearing loss. Accurate diagnosis of syndromic hearing loss can guide discussions regarding prognosis and appropriate management options for the hearing impairment.

SUMMARY

A significant portion of childhood hearing loss is associated with a syndrome. Depending on the syndrome, surgical intervention including a bone-anchored hearing aid or cochlear implant may be helpful. In the future, targeted gene therapies may become a viable option for treating syndromic hearing loss.

Toward a Conceptual and Methodological Shift in Craniofacial Research

Objective:

To date, research investigating the psychological impact of craniofacial conditions has produced variability across outcomes. The aims of this article were to summarize the challenges that may contribute to this variability, and to offer alternative perspectives and approaches to guide future research and practice.

Design:

A comprehensive evaluation of papers exploring adjustment to congenital craniofacial conditions was conducted. Methodological approaches and underlying conceptual issues were identified and summarized.

Results:

The conceptual limitations identified include inherent challenges pertaining to the multifactorial and fluctuating nature of adjustment, a lack of consensus regarding the primary constituents of a positive outcome, scant use of appropriate models and theories, and a predominant focus on “deficits” over “strengths.” The methodological shortcomings identified include a lack of representative samples, biomedical inclusion/exclusion criteria, inconsistency in measurement, a relative absence of the patient perspective, variability in approaches to data analysis and interpretation, and the failure to draw on knowledge from other disciplines and related fields of health research. Findings are believed to be relevant to all disciplines involved in craniofacial research and practice.

Conclusions:

Existing literature remains markedly affected by a range of conceptual and methodological challenges, despite these challenges being identified 25 years ago. The present article proposes that a shift in the way we conceptualize and study craniofacial conditions is needed, in order to construct a comprehensive understanding of adjustment to craniofacial conditions, and to address the key unanswered questions important to all stakeholders.

Restoration of polr1c in Early Embryogenesis Rescues the Type 3 Treacher Collins Syndrome Facial Malformation Phenotype in Zebrafish

Treacher Collins syndrome (TCS) is a rare congenital birth disorder (1 in 50,000 live births) characterized by severe craniofacial defects. Recently, the authors' group unfolded the pathogenesis of polr1c Type 3 TCS by using the zebrafish model. Facial development depends on the neural crest cells, in which polr1c plays a role in regulating their expression. In this study, the authors aimed to identify the functional time window of polr1c in TCS by the use of photo-morpholino to restore the polr1c expression at different time points. Results suggested that the restoration of polr1c at 8 hours after fertilization could rescue the TCS facial malformation phenotype by correcting the neural crest cell expression, reducing the cell death, and normalizing the p53 mRNA expression level in the rescued morphants. However, such recovery could not be reproduced if the polr1c is restored after 30 hours after fertilization.

Mandibulofacial dysostosis Bauru type: Refining the phenotype

Mandibulofacial dysostosis (MFD) Bauru type (OMIM 604830) is a rare genetic condition characterized mainly by malar hypoplasia, orofacial cleft, and micrognathia. Here, we describe the clinical and radiographic sings of 13 individuals (12 female and 1 male) from eight unrelated kindreds with MFD Bauru type, including four previously reported cases, treated at the Hospital for Rehabilitation of Craniofacial Anomalies. The clinical phenotype was characterized by severe underdevelopment of mandible, midface hypoplasia, orofacial cleft, bitemporal narrowing, mild upper eyelid down slanting, high nasal bridge, thick and everted lower lip, minor ears abnormalities, and hearing loss. Radiographic aspects included downslanting of zygomatic arch, maxillary hypoplasia, microretrognathia, hypoplastic mandibular condyles, and ectopic external auditory canal. Recurrence was observed in two of eight families and the affected distribution pattern was compatible with autosomal dominant inheritance in one and autosomal recessive in another, indicating possible genetic heterogeneity for this condition. Clinical and radiographic findings in this report contribute to the delineation of this rare MFD.

How do we recognize the child with OSAS?

Obstructive sleep-disordered breathing includes a spectrum of clinical entities with variable severity ranging from primary snoring to obstructive sleep apnea syndrome (OSAS). The clinical suspicion for OSAS is most often raised by parental report of specific symptoms and/or abnormalities identified by the physical examination which predispose to upper airway obstruction (e.g., adenotonsillar hypertrophy, obesity, craniofacial abnormalities, neuromuscular disorders). Symptoms and signs of OSAS are classified into those directly related to the intermittent pharyngeal airway obstruction (e.g., parental report of snoring, apneic events) and into morbidity resulting from the upper airway obstruction (e.g., increased daytime sleepiness, hyperactivity, poor school performance, inadequate somatic growth rate or enuresis). History of premature birth and a family history of OSAS as well as obesity and African American ethnicity are associated with increased risk of sleep-disordered breathing in childhood. Polysomnography is the gold standard method for the diagnosis of OSAS but may not be always feasible, especially in low-income countries or non-tertiary hospitals. Nocturnal oximetry and/or sleep questionnaires may be used to identify the child at high risk of OSAS when polysomnography is not an option. Endoscopy and MRI of the upper airway may help to identify the level(s) of upper airway obstruction and to evaluate the dynamic mechanics of the upper airway, especially in children with combined abnormalities. Pediatr Pulmonol. 2017;52:260-271. © 2016 Wiley Periodicals, Inc.

Treacher Collins syndrome: New insights from animal models

Treacher Collins syndrome (TCS, OMIM: 154500), an autosomal-dominant craniofacial developmental syndrome that occurs in 1 out of every 50,000 live births, is characterized by craniofacial malformation. Mutations in TCOF1, POLR1C, or POLR1D have been identified in affected individuals. In addition to established mouse models, zebrafish models have recently emerged as an valuable method to study facial disease. In this report, we summarized the two updated articles working on the pathogenesis of the newly identified polr1c and polr1d TCS mutations (Lau et al., 2016; Noack Watt et al., 2016) and discussed the possibility of using the anti-oxidants to prevent or rescue the TCS facial phenotype (Sakai et al., 2016). Taken together, this article provides an update on the disease from basic information to pathogenesis, and further summarizes the suggested therapies from recent laboratory research.