Surgical Outcome and Treatment Trends in 1289 Infants with Micrognathia: A Multicenter Cohort

BACKGROUND

Studies of infants with micrognathia, especially Robin sequence, are limited by its rarity and both phenotypic and diagnostic variability. Most knowledge of this condition is sourced from small, single-institution samples.

METHODS

This is a cross-sectional study including infants with micrognathia admitted to 38 Children's Hospital Neonatal Consortium centers from 2010 through 2020. Predictor variables included demographic data, birth characteristics, cleft, and syndrome status. Outcome variables included length of stay, death, feeding or respiratory support, and secondary airway operations.

RESULTS

A total of 1289 infants with micrognathia had surgery to correct upper airway obstruction. Mean age and weight at operation were 34.8 ± 1.8 weeks and 3515.4 ± 42 g, respectively. A syndromic diagnosis was made in 150 (11.6%) patients, with Stickler (5.4%) and Treacher Collins (2.2%) syndromes being the most common. Operations included mandibular distraction osteogenesis (MDO) in 66.3%, tracheostomy in 25.4%, and tongue-lip adhesion (TLA) in 8.3%. Patients receiving a tracheostomy had lower birthweight, head circumference, gestational age, and Apgar scores. Patients undergoing MDO were less likely to need a second airway operation compared with patients undergoing TLA (3.5% versus 17.8%; P < 0.001). The proportion of infants feeding exclusively orally at hospital discharge differed significantly, from most to least: MDO, TLA, and tracheostomy. Hospital length of stay was not statistically different for patients who had MDO or TLA, but was longer for those with primary tracheostomy. The mortality rate was low for all operations (0.5%).

CONCLUSIONS

In this surgical patient cohort, MDO was associated with shorter hospital stay, improved oral feeding, and lower rates of secondary airway operations. Prospective multicenter studies are necessary to support these conclusions.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, III.

Adults with Treacher Collins Syndrome Share Comparable 3D Upper Airway Dimensions with Nonsyndromic Individuals

Purpose

Sleep apnea symptoms, such as snoring and daytime somnolence, are commonly observed in individuals with Treacher Collins Syndrome (TCS) and may be related to airway obstruction due to micro- and retro-gnathia. This study aims to three-dimensionally evaluate the upper airway using cone-beam computed tomography (CBCT) exams of adolescents (TCS-ADOL) and adults (TCS-ADUL) with TCS compared to a nonsyndromic group (CON).

Materials and Methods

Twenty-six CBCT exams were divided into three groups: TCS-ADOL (n = 7) (13.14 ± 1.67 years): CBCT exams of TCS adolescents; TCS-ADUL (n = 10) (21.80 ± 4.39 years): CBCT exams of TCS adults; and CON (n = 9) (25.33 ± 8.57 years): CBCT exams of adult nonsyndromic individuals with Class II skeletal pattern. The variables analyzed were (1) total upper airway volume; (2) nasal cavity volume; (3) total pharyngeal volume; (4) nasopharyngeal volume; (5) oropharyngeal volume; (6) pharyngeal minimal cross-sectional area; (7) pharyngeal length; and (8) pharyngeal depth. Scans were analyzed by two examiners, and intra- and inter-rater agreement was calculated. A p-value of ≤0.05 was considered significant.

Results

Although not statistically significant, the TCS-ADUL group showed decreased airway volume and minimal cross-sectional areas compared to the CON group. There were also significant differences between TCS-ADOL and TCS-ADUL, with significantly lower airway volumes in the TCS-ADOL group. Strong positive correlations were found between certain airway measurements in the TCS-ADOL group, which were not observed in adults.

Conclusions

The upper airways of adults with TCS are dimensionally similar to those of nonsyndromic individuals, despite absolute value reductions found in the syndromic group. The reduced airway in the adolescent population suggests significant potential for growth, mainly in pharyngeal dimensions.

Bite Force, Masticatory Performance, and Nutritional Status of Adult Individuals With Treacher Collins Syndrome

OBJECTIVE

To characterize the stomatognathic system of individuals with Treacher Collins syndrome (TCS) by assessing bite force (BF) and masticatory performance (MP) and to evaluate the nutritional status (NS) of this population through anthropometric measurements.

DESIGN

Cross-sectional study.

SETTING

A public tertiary care hospital.

PATIENTS

Forty-one individuals were divided into 2 groups: (1) Control (CON): 20 control adults with class I skeletal pattern and (2) TCS: 21 adults with TCS.

INTERVENTIONS

BF measurement was assessed using a gnathodynamometer (IDDK Kratos). MP assessment was done using Image J-NIH software, by calculating the particles size of food submitted to standard chewing cycles ). NS was assessed based on body mass index (BMI).

MAIN OUTCOME MEASURES

Based on the craniofacial dysmorphology, it is our hypothesis that this population present a dysfunctional masticatory system, which can negatively impact NS.

RESULTS

Means BF values for the TCS were significantly reduced when compared with the CON group and corresponded to 170.9  ±  109.4N and 431.6  ±  134.1N (right molar [RM]) and 171.2  ±  93.9N and 427.4  ±  147.8N (left molar [LM]), respectively (P < .05). Although no significant differences were observed, the mean particle size of the TCS was greater when compared with the CON group and corresponded to 1.58  ±  1.93 mm2 and 0.66  ±  0.52 mm2, respectively. Although statistically similar mean values of BMIs were observed on both groups (CON  =  23.4  ±  4.7/TCS  =  23.4  ±  6.1), underweight and overweight individuals were found in 48% of the individuals with TCS and in 15% of the CON group participants.

CONCLUSION

Individuals with TCS showed a significant BF reduction, but no differences were observed in MP and NS when compared with the control individuals.

Effects of 3D Airway Geometry on the Airflow of Adults with Cleft Lip and Palate and Obstructive Sleep Apnea: A Functional Imaging Study

Objective  Individuals with cleft lip and palate (CLP) are at a high risk of developing obstructive sleep apnea (OSA). Hypothetically, the severity of OSA might be associated with the morphology of the upper airway (UAW) and the characteristics of the airflow. Thus, the present study aimed to assess and compare, in adults with CLP and skeletal class-III discrepancy, with or without OSA, simulations of airflow resistance and pressure according to the geometrical characteristics of the UAW and cephalometric parameters. Materials and Methods  According to the results of type-I polysomnography tests, the sample ( n  = 21) was allocated in 2 groups: 1) without OSA (N-OSA; n  = 6); and 2) with OSA (OSA; n  = 15). Cephalometric measurements were performed on the cone-beam computed tomography (CBCT) scans of the groups. After three-dimensional (3D) reconstructions, the volume (V) and minimal cross-sectional area (mCSA) of the UAW were generated. Computational fluid dynamics (CFD) simulations were used to assess key airflow characteristics. The results were presented at a significance level of 5%. Results  The UAW pressure values and airway resistance did not differ between the groups, but there was a tendency for more negative pressures (26%) and greater resistance (19%) in the OSA group. Volume and mCSA showed a moderate negative correlation with resistance and pressure. The more inferior the hyoid bone, the more negative the pressures generated on the pharyngeal walls. Conclusion  The position of the hyoid bone and the geometry of the UAW (V and mCSA) exerted effects on the airway-airflow resistance and pressure. However, key airflow characteristics did not differ among subjects with CLP, were they affected or not by OSA.

Obstructive Sleep Apnea in Adults with Treacher Collins Syndrome is Related with Altered Anthropometric Measurements, Increased Blood Pressure and Impaired Quality of Life

Objectives  This study aimed at evaluating the risk for obstructive sleep apnea (OSA) and its frequency in adults with Treacher Collins syndrome (TCS). The association of OSA with excessive daytime sleepiness (EDS), respiratory symptoms, and clinical variables was also assessed. Material and Methods  The subjects were prospectively screened for OSA through the Berlin Questionnaire and type I polysomnography. The Epworth Sleepiness Scale and the Respiratory Symptoms Questionnaire were used for assessing OSA-related symptoms. Quality of life was assessed by means of the Short Form 36 Health Survey. Results  The sample comprised 20 adults with TCS (55.0% female), aged 22.6 ± 5.8 years. Mean values of systemic blood pressure (113.0 ± 12.6/68.0 ± 9.5mmHg), body mass index (22.9 ± 5.9kg/m ² ), neck (34.1 ± 4.3cm), and waist circumference (80.4 ± 13.6cm) characterized the sample. A high risk for OSA was detected in 35% of the sample. Polysomnography results indicated an OSA frequency of 44.4%, with a median apnea-hypopnea index (AHI) value of 3.8 events/hour (minimum = 0.2; maximum = 77.5). Snoring (75.0%), nasal obstruction (70.0%) and EDS (20.0%) were the reported OSA-related symptoms. Quality of life median scores were 72.3 points (minimum = 45.0; maximum = 91.1). Strong positive correlations between AHI versus waist circumference and AHI versus systolic blood pressure were found. Moderate positive correlations between AHI versus body mass index and AHI versus neck circumference were detected. Negative correlation between AHI versus vitality were also observed. Conclusion  Adults with TCS are at high risk for OSA, which is associated with respiratory symptoms, altered anthropometric measurements, increased systolic pressure and impairment of quality of life.

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.

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.

Adults With Unilateral Cleft Lip and Palate Present Reduced Internal Nasal Volumes: Findings of a Three-Dimensional Morphometric Assessment in Cone-Beam Computed Tomography Scans

ABSTRACT

The main purpose was to assess and compare nasal cavity (NC) volumes among adults with unilateral (UCLP) and bilateral cleft lip and palate (BCLP) and in noncleft controls (CON), by means of cone-beam computed tomography (CBCT) three-dimensional reconstructions. Forty-five scans of individuals with class III skeletal pattern, matched by age, were gathered in 3 groups: UCLP (n = 15), BCLP (n = 15) and (CON) (n = 15). The NC volume was assessed three-dimensionally, using Dolphin 11.8 software. Descriptive normally distributed data was presented as mean (±SD). Comparisons of NC volume among groups was performed using ANOVA test (P ≤ 0.05). The NC mean volumes corresponded to 14.7(±2.2) cm3 (UCLP), 17.1(±2.2) cm3 (BCLP) and 18.1(±3.8) cm3 (CON), respectively. UCLP individuals presented a significantly reduced NC volume when compared to controls (P = 0.006). No differences were observed between UCLP versus BCLP or BCLP versus CON. The intraclass correlation coefficient suggested a high intra- and inter-examiners agreement (>.075). Individuals with unilateral cleft lip and palate presented reduced NC when compared to individuals without cleft lip and palate. CBCT scans can be considered a highly accurate tool for morphometric assessments of craniofacial structures.

[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.