The Outcome of Mandibular Distraction Osteogenesis in Infants with Severe Pierre Robin Sequence in Vietnam

The purpose of this study was to provide the experience of a single center with mandibular distraction osteogenesis (MDO) in Pierre Robin Sequence (PRS) patients. A longitudinal research analysis was conducted to identify PRS patients who underwent MDO at Vietnam National Children's Hospital between 2019 and 2021. The following criteria were used to determine inclusion: 1) those pediatric patients with PRS who were not well handled with conservative therapy, 2) those who received MDO with internal mandibular distractors, and 3) no previous treatment elsewhere. Demographic data, postoperative complications, and surgical results were all evaluated. The inclusion criteria were met by 73 patients. There were no difficulties associated with our distraction strategy. The majority of individuals with tracheostomies were successfully decannulated, and the remainder were able to avoid tracheostomies. Using MDO in PRS is an effective technique to avoid future airway issues. The success rate was lower and the complication rate higher for patients who had a tracheotomy before distraction and for those who underwent distraction at an age older than 2 months. The presence of laryngomalacia, gastric reflux disease, cardiac abnormalities, and GI anomalies did not increase the likelihood of MDO failure in PRS patients.

The Impact of Mandibular Distraction Osteogenesis on Cephalometric Measurements in Infants with Pierre Robin Sequence

BACKGROUND

The obstruction of the upper airway (UAO) in infants diagnosed with Robin Sequence (RS) is caused by micrognathia, and in severe cases, it can result in obstructive sleep apnea (OSA). Mandibular distraction osteogenesis (MDO) is a secure and efficient remedy for significant UAO. However, there is insufficient data on the related cephalometric changes. Therefore, this study meticulously analyzes the mandibular cephalometric changes in infants with RS who have undergone MDO using internal devices. The aim is to gain a more comprehensive understanding of the short- and long-term impacts of distraction on the mandible.

METHODS

The study examined 73 consecutive cases of mandibular distraction osteogenesis (MDO) performed by a single surgeon. Preoperative and postoperative lateral cephalograms, as well as CT scans of the mandible, were utilized to assess population averages for both time points. A two-sample T-Test with equal variance was used for this analysis.

RESULTS

After the MDO procedure, 19 out of 21 cephalometric parameters exhibited significant morphological changes. On average, there were notable improvements of 20.3 mm (60.7%) in length, 9.8 mm (49.7%) in height, 12.6 mm (36.1%) in width, and 211% in airway parameters. However, most parameters showed only mild regression at the time of device removal and 6 to 12 months post-MDO. Nonetheless, the cephalometric parameters remained significantly improved compared to the preoperative measurements.

CONCLUSIONS

The use of cephalometric measurement is a potent approach that provides a clear and measurable understanding of how MDO influences both immediate and long-term growth of the mandible. This quantitative assessment of the effects of mandibular distraction allows for the refinement of surgical techniques and the optimization of outcomes. Therefore, incorporating cephalometric measurements in the evaluation of patients undergoing MDO can lead to better surgical planning and more favorable results.

Prevalence and Management of Laryngomalacia in Patients With Pierre Robin Sequence

OBJECTIVE

To characterize the prevalence and presentation of laryngomalacia and efficacy of supraglottoplasty (SGP) in a cohort of patients with Pierre Robin Sequence (PRS).

DESIGN

Retrospective cohort study.

SETTING

Tertiary-care children's hospital.

PATIENTS, PARTICIPANTS

Consecutive patients with PRS born between January 2010 and June 2018.

MAIN OUTCOME MEASURES

Chart review included demographics, comorbid airway obstruction including laryngomalacia, timing of surgical interventions, clinical symptoms, sleep study data, and modified barium swallow study data.

126 patients with PRS were included; 54% had an associated syndrome, 64% had an overt cleft palate, and 22% had a submucous cleft palate. 64/126 were noted to have laryngomalacia (51%). Patients with concurrent PRS and laryngomalacia were significantly more likely to have submucous cleft palate (P = .005) and present with aspiration with cough (P = .01) compared to patients with PRS without laryngomalacia. Patients with concurrent laryngomalacia and PRS showed a significant decrease in apnea-hypopnea index (AHI) and obstructive AHI (OAHI) after mandibular distraction, with a median AHI and OAHI improvement of 22.3 (P = .001) and 19.8 (P = .002), respectively. Patients who underwent only SGP did not show significant improvement in these parameters (P = .112 for AHI, P = .064 for OAHI).

The prevalence of laryngomalacia in our PRS cohort was 51%. Patients with PRS and laryngomalacia are more likely to present with overt aspiration compared to patients with PRS without laryngomalacia. These data support that laryngomalacia does not appear to be a contraindication to pursuing MDO.

Mandibular Measurements at the 20-Week Anatomy Ultrasound as a Prenatal Diagnostic Predictor of Pierre Robin Sequence

BACKGROUND

Pierre Robin Sequence (PRS) is characterized by micrognathia, glossoptosis, and upper airway obstruction. Early recognition and appropriate perinatal management is crucial for optimizing outcomes. This study aimed to evaluate 20-week fetal ultrasounds to determine if specific mandibular measurements could predict PRS diagnosis and disease severity.

METHODS

A retrospective case-control study of 48 patients with PRS and gender-matched controls was performed. Medical records were reviewed for respiratory and surgical interventions. Three parameters to assess micrognathia were measured on mid-sagittal profile ultrasound images: frontal nasal-mental angle (FNMA), facial-maxillary angle (FMA), and alveolar overjet. Student's t-test and univariate logistic regression was performed. P ≤ 0.05 was considered statistically significant.

RESULTS

Patients with PRS demonstrated a significantly smaller mean FNMA compared to the control group, 129.3 ± 8.6° and 137.4 ± 3.2°, respectively (p < 0.0001), as well as significantly smaller mean FMA, 63.2 ± 9.2° and 74.8 ± 6.1°, respectively (p < 0.0001). The PRS group also demonstrated significantly larger mean alveolar overjet compared to the control group, 3.9 ± 1.4 mm and 2.1 ± 0.9 mm, respectively (p < 0.0001). The odds of respiratory intervention increased among cases when FMA was <68°. Additionally, there was a significant difference in median overjet between patients with PRS who did and did not require respiratory intervention.

CONCLUSIONS

Mandibular features on the 20-week ultrasound can be measured to predict diagnosis and severity of PRS. This is an important first step to prepare for potential respiratory intervention at delivery to minimize perinatal hypoxia. Alveolar overjet, previously not described in prenatal ultrasound literature, is measurable and has utility in prenatal screening for PRS, as do FMA and FNMA.

Fetal Micro and Macroglossia: Defining Normal Fetal Tongue Size

OBJECTIVES

Abnormal fetal tongue size is a phenotypic feature of various syndromes including Beckwith-Wiedemann, Pierre-Robin, oromandibular limb hypoplasia, chromosomal aberrations, etc. Current data regarding normal fetal tongue size are limited. Hence, micro/macroglossia are subjectively determined. The aim of the study was to construct a contemporary fetal tongue nomogram and to assess its clinical contribution.

METHODS

A prospective cross-sectional study was performed in well dated, low risk, singleton pregnancies. Fetal tongues were measured by 5 trained sonographers. Highest quality images were selected. Intra- and interobserver variability was assessed. Tongue length, width, area, and circumference 1st to 99th centiles were calculated for each gestational week. Based on the normal tongue size charts, we created a Tongue Centile Calculator.

RESULTS

Over 18 months, 664 tongue measurements were performed. A cubic polynomial regression model best described the correlation between tongue size and gestational age. The correlation coefficient (r² ) was 0.934, 0.932, 0.925, and 0.953 for tongue length, width, area, and circumference, respectively (P < .001). Intra- and interobserver variability had high interclass correlation coefficients (>0.9). Using the new charts, we were able to identify 2 cases of macroglossia, subsequently diagnosed with Beckwith-Wiedemann, and 4 cases of microglossia, 3 associated with Pierre-Robin sequence, and 1 associated with persistent buccopharyngeal membrane.

CONCLUSIONS

We present novel fetal tongue size charts from 13 to 40 weeks of gestation. Clinical application of these nomograms may be beneficial in the prenatal diagnosis of syndromes or malformations associated with abnormal fetal tongue size.

The Safety and Efficacy of Mandibular Distraction Osteogenesis Among Infants Less Than 3 kg

OBJECTIVES/HYPOTHESIS

Mandibular distraction osteogenesis (MDO) is a safe and effective surgery to address respiratory and feeding issues due to micrognathia in patients with Robin Sequence (RS). Previous studies examining postoperative complications in neonates receiving MDO have considered 4 kg as the cut-off for low weight; however, an increasing number of MDO interventions are performed in infants <4 kg. To determine if a weight <3 kg at time of MDO is a risk factor for postoperative complications or need for subsequent tracheostomy or gastrostomy tube (G-tube).

STUDY DESIGN

Retrospective chart review.

METHODS

A retrospective review of all infants <6 months of age undergoing MDO at two tertiary pediatric hospitals from 2008 to 2018. Demographic data, syndromic status, weight, and age at time of surgery, length of postoperative hospital stay, and postoperative outcomes were recorded including tracheostomy placement, G-tube placement, hardware infection, reintubation, facial/marginal mandibular nerve damage, and need for revision MDO.

RESULTS

Sixty-nine patients with RS were included. The mean age at MDO was 25 ± 20 days and mean weight was 3.32 ± 0.44 kg. There was no statistically significant correlation between weight (P = .699) or age (P = .422) and unfavorable postoperative outcomes. No patients (0%) underwent tracheostomy pre-MDO. Two patients (2.9%) required tracheostomy postsurgery; neither was <3 kg. Eight patients (11.6%) required a G-tube postoperatively.

CONCLUSION

Newborns <3 kg who undergo MDO experience the same rates of success and complication as larger infants, suggesting that MDO is a safe and efficacious procedure in infants less than 3 kg. Laryngoscope, 2021.

Neonatal Functional Treatment for Pierre Robin Sequence

Objective

Pierre Robin Sequence (PRS) is a heterogeneous pathological condition characterized by the coexistence of micrognathia, glossoptosis, and cleft palate, resulting in upper airway tract obstruction. Among the treatment modalities, the orthodontic approach is one part of the comprehensive care of those patients and will be present in the treatment modalities during all the growth period of the child.

Methods

All patients with PRS observed in the period 2013-2017 were treated with a definite functional approach. The results were retrospectively analyzed with regard to functional outcome, total treatment time, and number of plates provided for a single patient.

Results

In all the patients, the indicated treatment protocol has been applied as early impression and plate supply, stimulation of bottle feeding with the use of the plate, eventual substitution of the plate if no more adequate to the transverse and sagittal growth of the palate, and continuing the use until the surgical closure of the cleft. All the patients showed a positive outcome to the proposed treatment approach, evaluated with regard to the incidence of feeding improvement and weight gain, to the limit for the surgical phase, in the absence of adverse effects.

Conclusion

The use of a functional obturator plate, removing functional alterations to mandibular growth, reduces and, in some cases, eliminates the need for surgical intervention. As also stated in the literature, if despite the presence of the plate nutritional problems persist, immediate different surgical approaches, mainly mandibular osteodistraction, become necessary.

Kyphomelic dysplasia, Pierre Robin Sequence and pregnant

We present the anaesthetic management of a parturient with kyphomelic dysplasia and Pierre Robin Sequence who underwent elective caesarean delivery. Potential anaesthetic issues and management strategies are discussed.

Feeding practices and growth of infants with Pierre Robin Sequence

OBJECTIVES

To assess the impact of feeding practices on growth in infants with Pierre Robin Sequence (PRS) during their inpatient stay in a neonatal intensive care unit in a large tertiary paediatric hospital setting.

METHODS

A retrospective review of feeding practices in infants with PRS was conducted between January 2006 and September 2017. Baseline demographics, nutrition-related and general outcomes were collected. Feeding difficulties, length of stay (LOS) and malnutrition were the primary outcome measures. Feeding difficulties included absence or poor-quality suck, episodes of aspiration, use of proton pump inhibitors or multiple episodes of vomiting. Malnutrition was classified as a weight-for-age Z score of < -1.

RESULTS

Analysis was conducted on 49 infants with PRS that met eligibility criteria. Feeding difficulties correlated with a longer LOS (24.1 vs 6.8 days (p = 0.001)) Z-scores differed significantly between birth and discharge (0.21(1.84) vs -1.27(2.14)) (p < 0.001*) with malnutrition being evident in 26 infants of which only 17 infants were seen by a dietitian. Presence of intrauterine growth restriction (IUGR) increased the likelihood of malnutrition (OR 1.40(CI-1.11-1.77)).

CONCLUSION

Infants with PRS are highly likely to have feeding difficulties and malnutrition. Early intervention by a dietitian is recommended to reduce the impacts of feeding difficulties, meet elevated energy requirements and facilitate growth. Infants with a longer inpatient stay or presence of IUGR should have their growth and feeding routinely monitored.

Novel dental phenotype in non-syndromic Pierre Robin Sequence: A retrospective study

OBJECTIVE

The objective was to investigate dental phenotypes in individuals with non-syndromic Pierre Robin Sequence (ns-PRS) and compare the prevalence of these phenotypes with subjects with non-syndromic cleft palate (ns-CP) and a control group with subjects without any craniofacial anomalies.

METHODS

A total of 760 panoramic radiographs of 330 individuals (110 with ns-PRS; 110 with ns-CP and 110 without any malformations) were digitized and evaluated regarding the diagnosis of taurodontism, tooth agenesis, root dilaceration and tooth transposition. Chi-square test was applied to compare the occurrence of dental phenotypes between groups. A P value of less than 0.05 was considered statistically significant.

RESULTS

Total prevalence of dental phenotypes was 94.5% of ns-PRS; 54.5% of ns-CP and 59.1% of the control group subjects with a statistically significant difference for the ns-PRS when compared to the other two groups. Two dental phenotypes, taurodontism and dental agenesis were identified with statistically significant higher prevalences in subjects with ns-PRS when compared with the ns-CP group and the control group (p < 0.001). Taurodontism was the most prevalent dental phenotype, with 92.73% in the ns-PRS group, 40.91% for ns-CP and 44.55% in the control group. Tooth agenesis had a prevalence of 22.7% for ns-PRS, 4.5% for ns-CP and no case in the control group. For the prevalence of root dilaceration and tooth transposition, no statistically significant differences were observed between the three groups.

CONCLUSIONS

Due to the high frequency of taurodontism in individuals with ns-PRS, we suggested that this novel phenotype would be important in the phenotypic screening of ns-PRS and could be considered as a phenotype associated with ns-PRS.

Difficult airway intubation simulation using Bonfils fiberscope and rigid fiberscope for surgical training

INTRODUCTION

Pediatric otolaryngologists are frequently called to assist in difficult airway management in newborns with Pierre Robin Sequence (PRS) who have microretrognathia, glossoptosis, and an anterior larynx. The Bonfils fiberscope (BF) is a curved rigid scope designed to provide superior visualization in the anterior larynx.

OBJECTIVE

(1) to assess whether BF provides an improvement in intubation success rate, time to intubation, or airway visualization as compared to rigid fiberscope (RF) in a difficult airway simulation setting and (2) to determine whether a training program for BF can improve time to intubation through practice trials.

METHODS

Six right-handed trainees completed five trials on each of the three following airway models using the BF and RF: normal anatomy, anterior larynx and PRS. The normal larynx model was intubated only with RF. Main outcome measures were the time needed for tracheal intubation and Cormack-Lehane classification (1-4).

RESULTS

The majority of the intubation trials showed a statistically significant difference between first and last completion times (p < .05) suggesting construct validity. Only the anterior larynx trials with BF did not demonstrate an improvement in time to intubation between first and last attempts (p < .3125). For the PRS retrognathia model, there was no statistically significant difference in time to intubation between using the BF and the RF (p < .44); in the anterior larynx model, the RF yielded a faster time to intubation than the BF on the final trial attempts (p < .0313). By Cormack-Lehane classification measures, laryngeal visualization by the BF was better than RF in the PRS manikin (p < .0022) while there was no significant difference in grade scores for the anterior larynx manikin (p < .45). All six trainees reported an improved visualization of the larynx with the BF compared to the RF for both the anterior larynx and PRS manikins; at the end of the trial runs, all participants noted an improvement in comfort level using the BF.

CONCLUSION

The difficult airway simulation model is feasible for surgical training. BF adds superior visualization of the anterior larynx in PRS. Otolaryngology training programs may include BF as a supplemental tool in addition to RF as a part of the airway equipment training since there is significant improvement in time to intubation with consecutive practice trials and superior laryngeal visualization.

Can telemetry data obviate the need for sleep studies in Pierre Robin Sequence?

OBJECTIVE

This study looks to correlate telemetry data gathered on patients with Pierre Robin Sequence (PRS) with sleep study data. Strong correlation might allow obstructive sleep apnea (OSA) to be reasonably predicted without the need for sleep study.

METHODS

Charts from forty-six infants with PRS who presented to our children's hospital between 2005 and 2015 and received a polysomnogram (PSG) prior to surgical intervention were retrospectively reviewed. Correlations and scatterplots were used to compare average daily oxygen nadir, overall oxygen nadir, and average number of daily desaturations from telemetry data with apnea-hypopnea index (AHI) and oxygen nadir on sleep study. Results were also categorized into groups of AHI ≥ or <10 and oxygen nadir ≥ or <80% for chi-squared analysis.

RESULTS

Our data did not show significant correlations between telemetry data and sleep study data. Patients with O2 nadir below 80% on telemetry were not more likely to have an O2 nadir below 80% on sleep study. Patients with an average O2 nadir below 80% did show some correlation with having an AHI greater than 10 on sleep study but this relationship did not reach significance. Of 22 patients who did not have any desaturations on telemetry below 80%, 16 (73%) had an AHI >10 on sleep study.

CONCLUSIONS

In the workup of infants with PRS, the index of suspicion is high for OSA. In our series, telemetry data was not useful in ruling out severe OSA. Thus our data do not support forgoing sleep study in patients with PRS and concern for OSA despite normal telemetry patterns.

Glossoptosis

Glossoptosis causes varying degrees of airway obstruction and feeding difficulties. It can occur as a consequence of micrognathia in Robin Sequence, but can also occur in children with hypotonia. Despite several attempts to classify severity in Robin Sequence patients, taking into account symptoms, presence of concomitant syndromes or malformations, and even endoscopic findings, there is still no general consensus. Furthermore, several management recommendations have been reported without an agreement about indications, efficacy, or risks of each treatment option. The present article provides an overview of clinical presentation, diagnosis, management, and prognosis of patients with glossoptosis.

Do patients with isolated Pierre Robin Sequence have worse outcomes after cleft palate repair: A systematic review

Cleft palate repair for Pierre Robin Sequence (PRS) patients has always been a challenge for surgeons and anesthetists. The aim of this systematic review is to investigate the outcome of cleft palate repair for PRS patients compared with cleft palate-only patients. All papers published before October 2014 were searched in the databases PubMed and MEDLINE. Search terms included "Pierre Robin Sequence," "cleft palate repair," and "speech result." Additional studies were identified by hand searching the reference lists of the papers retrieved from electronic search. Two independent reviewers assessed the eligibility of studies for inclusion, extracted the data, and assessed the quality of the studies. Six studies met the inclusion criteria. All but one study had multiple deficiencies in study designs. Four studies assessed the fistula rate of both groups, and all studies assessed some aspect of the speech results. Conflicting results and a lack of high-quality and long-term outcomes of reviewed studies provided no conclusive scientific evidence about whether the outcome of cleft palate repair for PRS patients was better or worse than cleft palate-only patients. Further well-designed, well-controlled, and long-term studies are needed.