Early Postnatal Development of the Mandible in Children with Isolated Cleft Palate and Children with Nonsyndromic Robin Sequence

Prospective cohort study on facial profile changes in infants with Robin sequence and healthy controls

BACKGROUND

Various conservative and surgical approaches exist to treat Robin sequence (RS), but their effects on facial profile and mandibular catch-up growth are unclear. A functional treatment concept, used in our centre for 25 years, includes an individualized palatal plate with a velo-pharyngeal extension and intensive feeding training.

METHODS

We performed a prospective study to objectively describe facial profiles in infants with RS treated with the above concept. Infants with isolated RS were admitted to our tertiary perinatal and national referral centre for craniofacial malformations between May 2018 and Nov 2019. Infants with RS received 3D-photographs during clinically indicated visits. Healthy controls were recruited from Dec 2018 to Sep 2019 and received 3D-photographs every 3 months. The digitally measured jaw index (JI), defined as alveolar overjet (O) x maxillary arch (U)/mandibular arch (L), and the soft tissue reference points A'-point, Nasion', B'-point angle (ANB'), describing the relative position of maxilla to mandible, were evaluated. Linear mixed models were used to examine time trajectories in JI and ANB'.

RESULTS

A total of 207 3D images, obtained in 19 infants with RS and 32 controls, were analysed. JI and ANB' decreased over time in both groups [for JI - 0.18 (95% CI - 0.25 to - 0.10); for ANB': - 0.40° per month [(95% CI - 0.48 to - 0.32)]] but remained lower in controls [for JI - 2.5 (95% CI - 3.2 to - 1.8); for ANB'-1.7° (95% CI - 2.4 to - 1.0)]. Also, the ANB' model showed a significant effect of the interaction term diagnosis x age.

CONCLUSIONS

Based on longitudinal 3D images, we describe changes in objective parameters of facial profile in infants with and without RS during the first year of life. Our findings indicate catch-up growth in infants treated for RS. Video Abstract.

Growth Patterns of the Maxillomandibular Complex in Preadolescent Patients With Pierre-Robin Sequence Using Cluster Analysis and Longitudinal Follow-Up Cephalometric Data

OBJECTIVE

To investigate the growth patterns of the maxillomandibular complex in preadolescent patients with Pierre-Robin sequence (PRS).

METHODS

The samples consisted of 20 preadolescent PRS patients who had cleft palate and did not undergo growth-modification therapy or surgical intervention [6 boys and 14 girls; mean age of lateral cephalograms taken, 8.8 y (T1) and 13.7 y (T2)]. According to k-means cluster analysis, four clusters were defined over 3 major groups at T1: (1) Both very retrusive maxilla and mandible group: Cluster-4 [n=4, very large gonial angle, very low facial height ratio (FHR)] and Cluster-1 (n=5, small gonial angle, normal FHR); (2) Retrusive maxilla and very retrusive mandible group (Cluster-3, n=7, normal gonial angle, very low FHR); and (3) Both normal maxilla and mandible group (Cluster-2, n=4, very large gonial angle, low FHR). Seven angular and ratio variables [sella-nasion-A point (SNA), sella-nasion-B point (SNB), A point-nasion-B point (ANB), saddle angle, gonial angle, mandibular-body-length/anterior-cranial-base-length (MBL/ACBL), and FHR] at T1 and T2 and growth change from T1 to T2 were investigated.

RESULTS

At T1, SNA, SNB, saddle angle, gonial angle (all P<0.05), and FHR (P<0.01) showed significant difference among 4 clusters. At T2, SNA, SNB and gonial angle (all P<0.05) still showed significant difference among 4 clusters. During T1 to T2, there was no significant change in variables at each cluster except an increase in MBL/ACBL in Cluster-1 and FHR in Cluster-3 (all P<0.05).

CONCLUSIONS

Preadolescent PRS patients exhibited diverse skeletal phenotypes at T1, which did not change significantly from their original skeletal patterns by growth during T1 to T2.

Robin Sequence Facial Profile After Conservative Treatment: A Long-Term Follow-Up

INTRODUCTION

Robin sequence (RS) is a congenital clinical condition characterized by micrognathia, glossoptosis, and respiratory distress. Conservative methods could be responsible for releasing feeding and respiratory impairment but little information about mandibular growth is known in long-term follow-up.

OBJECTIVE

Assessing the longitudinal behavior of the facial profile of individuals with isolated RS who underwent conservative micrognathia treatment using photographs during the whole craniofacial growth.

METHODS

Photographs of the right facial profile of 100 patients were used (50 individuals with isolated RS and 50 individuals without craniofacial anomaly). The individuals with RS were evaluated at 3 different times (T1: infant, T2: mixed dentition, T3: permanent dentition) by measuring the facial convexity angle (FCA; G.Sn.Pog´). A comparison between T3 and control group (C), individuals without craniofacial anomalies and in permanent dentition, was also performed, checking the FCA, nasolabial angle (Ls.Sn.Cm), mentolabial fold (Li.Si.Pog´), facial inferior third (Sn.Gn´.C) angles and the ratio between middle anterior facial height and lower anterior facial height.

RESULTS

The T3 group showed an increased angle of facial convexity and increased facial inferior third angle and middle anterior facial height/lower anterior facial height ratio compared with the control group. In the longitudinal evaluation of individuals with isolated RS, significant differences were identified between T1 and T2 groups and T1 and T3 groups showing that the increased facial convexity was higher in the infants and that did not change significantly between the phases of mixed and permanent dentition.

CONCLUSIONS

RS showed increased facial convexity in all phases evaluated, but their convexity decreased with growth. When compared with individuals without craniofacial anomalies, the individuals continue to exhibit retrognathism in the permanent dentition. The lack of a mandible projection has led to a considerable number of orthognathic surgeries for the correction of discrepancies.

Prospective Evaluation of Children with Robin Sequence following Tübingen Palatal Plate Therapy

BACKGROUND

To assess the long-term functional orthodontic outcome of the Tübingen palatal plate (TPP) in children with Robin sequence (RS) in comparison to age- and sex-matched healthy controls.

METHODS

Between 09/2019 and 10/2020, we performed orthodontic assessments in 41 children at our Department of Orthodontics. Included were patients with RS (17 non-syndromic; four syndromic) and healthy controls (n = 22, average age in both groups 9.9 y). Facial analyses of 2D images, digital study casts and cephalometric measurements were made.

RESULTS

The orthodontic examinations showed no statistically significant group differences regarding functional extraoral, intraoral and pharyngeal parameters, or in skeletal patterns. The relationship between the upper and lower incisors was significantly increased (overjet 4 (2-10) vs. 3 (0-9) mm; p = 0.01) with a significant deficit in the lower face proportions (Jaw Index 4.15 (1.9-9.6) vs. 2.98 (0-9); p = 0.02; Facial convexity angle 157 (149-173) vs. 159 (149-170); p = 0.01).

CONCLUSION

Children with RS treated with the TPP showed normal long-term functional orthodontic outcomes, thanks to the functional adaption of the stomatognathic system. However, soft tissue growth did not completely match skeletal growth, resulting in a more convex facial profile.

Characterization of phenotypes and predominant skeletodental patterns in pre-adolescent patients with Pierre-Robin sequence

Objective

To investigate the phenotypes and predominant skeletodental pattern in pre-adolescent patients with Pierre–Robin sequence (PRS).

Methods

The samples consisted of 26 Korean pre-adolescent PRS patients (11 boys and 15 girls; mean age at the investigation, 9.20 years) treated at the Department of Orthodontics, Seoul National University Dental Hospital between 1998 and 2019. Dental phenotypes, oral manifestation, cephalometric variables, and associated anomalies were investigated and statistically analyzed.

Results

Congenitally missing teeth (CMT) were found in 34.6% of the patients (n = 9/26, 20 teeth, 2.22 teeth per patient) with 55.5% (n = 5/9) exhibiting bilaterally symmetric missing pattern. The mandibular incisors were the most common CMT (n = 11/20). Predominant skeletodental patterns included Class II relationship (57.7%), posteriorly positioned maxilla (76.9%) and mandible (92.3%), hyper-divergent pattern (92.3%), high gonial angle (65.4%), small mandibular body length to anterior cranial base ratio (65.4%), linguoversion of the maxillary incisors (76.9%), and linguoversion of the mandibular incisors (80.8%). Incomplete cleft palate (CP) of hard palate with complete CP of soft palate (61.5%) was the most frequently observed, followed by complete CP of hard and soft palate (19.2%) and CP of soft palate (19.2%) (p < 0.05). However, CP severity did not show a significant correlation with any cephalometric variables except incisor mandibular plane angle (p < 0.05). Five craniofacial and 15 extra-craniofacial anomalies were observed (53.8% patients); this implicated the need of routine screening.

Conclusions

The results might provide primary data for individualized diagnosis and treatment planning for pre-adolescent PRS patients despite a single institution-based data.

Characteristics of craniofacial morphology and factors affecting them in patients with isolated cleft palate

Background

Myriad maxillo-mandibular occlusal relationships are observed in patients with isolated cleft palate (ICP), unlike in patients with other cleft types, such as cleft lip and palate.

Objectives

This study aimed to categorise the characteristics of craniofacial morphology in patients with ICP, and investigate the clinical factors affecting these categorised morphological characteristics.

Methods

Thirty-six girls with ICP (age (mean ± SD): 5.36 ± 0.36 years) underwent cephalometric measurement. Their craniofacial morphology was categorised using cluster analysis. Profilograms were created and superimposed onto the standard Japanese profilograms to visualise the morphological characteristics of each group (cluster). The mean values and variations in the linear and angular measurements of each group were compared with the Japanese standards and statistically analysed using Dunnett’s test after the analysis of variance. Fisher’s exact test was used to analyse the differences between the cleft types (cleft in the hard and/or soft palate) and skills of the operating surgeons in the groups.

Results

Cluster analysis of craniofacial morphologies in patients with ICP resulted in the formation of three categories: the first cluster exhibited a relatively harmonious anteroposterior relationship between the maxilla and the mandible (22.2%); the second cluster exhibited crossbite owing to a significantly smaller maxilla (33.3%); and the third cluster exhibited a smaller mandible with posterior rotation showing skeletal class II malocclusion (44.4%). Differences in cleft types and surgeons were not associated with the distribution of patients in each cluster.

Conclusions

Patients with ICP exhibited characteristic morphological patterns, such as bimaxillary retrusion or severe mandibular retrusion, besides the anterior crossbite frequently found in patients with cleft lip and palate . Understanding the typical morphological characteristics could enable better diagnostic categorisation of patients with ICP, which may eventually improve orthodontic treatment planning.

A Comparison of Outcomes After Palatoplasty in Patients With Non-Syndromic Pierre Robin Sequence Versus Patients With Non-Syndromic Isolated Cleft Palate

The purpose of this retrospective study was to compare outcomes of cleft palate repair in patients with non-syndromic Pierre Robin sequence (NS-PRS) versus those with non-syndromic isolated cleft palate (NS-ICP). Pierre Robin sequence (PRS) was defined as a diagnosis of the triad of microretrognathia, glossoptosis, and cleft palate, and the severity of PRS was assessed based on the presence of respiratory and feeding problems. All patients underwent palatoplasty between January 2000 and December 2011. The authors examined age at palatoplasty, type of cleft palate, fistula rate, velopharyngeal (VP) function, nasal emission, hypernasality, and need for secondary speech surgery, in addition to PRS severity in the NS-PRS patients. A total of 15 NS-PRS patients and 40 NS-ICP patients were reviewed. The incidence of VP dysfunction, nasal emission, hypernasality, and secondary speech surgery was not significantly different between the NS-PRS patients and NS-ICP patients. Age at palatoplasty was significantly different between the 2 groups (P = 0.012) but type of CP was not (P = 1.00). Only 2 NS-PRS patients were classified as category III (severe), and all of the NS-PRS patients who had VP insufficiency were classified as PRS severity category I (not severe). The findings of this study indicate that NS-PRS patients may not have worse outcomes than NS-ICP patients.

The Hypoplasic Mandible: What Makes it Different From the Healthy Child?

OBJECTIVE

This study aimed to analyze the morphology of the hypoplasic mandible and its evolution during the growth period to better understand how it differs from the pediatric healthy mandible.

METHOD

Three-dimensional mandibular models of hypoplasic and healthy children aged from 39 gestational weeks to 7 years old were analyzed with a morphometric method including data clustering. Morphological distinctions between pathological and healthy mandibles were highlighted. Bilateral and unilateral mandibular hypoplasia were distinguished.

RESULTS

The study sample was composed of 31 hypoplasic children and as many sex- and age-matched healthy children. Morphological distinctions between pathological and healthy mandibles were highlighted only from the first year of life. In bilateral hypoplasia, the overall mandibular dimensions were reduced while there was only a ramus asymmetry in unilateral mandibular hypoplasia (mean ± SD of the difference between the Grp03c and Grp03b subgroups: 6.80 ± 6.37 - P value = 1.64e^-3 for the height of the left ramus versus 0.18 ± 4.18 - P value = .82 for the height of the right ramus). Supervised classification trees were built to identify the pathology and discriminate unilateral from bilateral mandibular hypoplasia (prediction rates = 81% and 84%, respectively).

CONCLUSIONS

Based on a morphometric analysis, we demonstrated that mandibular hypoplasia significantly impacts the mandibular morphology only from the first year of life, with a distinction between bilateral and unilateral hypoplasia.

Mandibular growth in infants with Robin sequence treated with the Tübingen palatal plate

Background

Robin sequence (RS) is characterized by mandibular retrognathia, glossoptosis and upper airway obstruction. Whether mandibular catch-up growth may occur in RS is yet controversial. Our functional and less invasive treatment including the Tübingen Palatal Plate (TPP), early oral feeding and orofacial stimulation may promote mandibular catch-up growth. We evaluated the effect of the Tübingen Palatal Plate on mandibular growth, expressed by the Jaw index, sleep study results and weight gain in infants admitted with isolated and syndromic RS, born at or referred to our center between 6/2015 and 5/2018.

Methods

Retrospective analysis of our electronic patient database that included data on jaw index measurements, sleep study results and standard deviation (Z-)scores for weight.

Results

Of 31 patients referred for RS treatment (22 isolated, 9 syndromic), we had data on the above parameters, determined at admission, discharge and 3 months after discharge, in 20. Jaw index at admission and 3-month follow-up was 8.8 (6.3–11.3) and 2.1 (2.0–4.0), respectively (median (IQR); p < 0.0001). Mixed-obstructive apnea index (MOAI) decreased from 9.7 (4.8–24.2) to 0.0 (0–1.3; p < 0.002). No significant correlation was observed between MOAI and Jaw Index, but MOAI correlated with the Maxillary/Mandibular arch ratio (r = 0.58; p < 0.001).

Z-scores for weight were similar at both time points at − 1.34 (− 1.76 – − 0.57) and − 1.50 (− 1.89 – − 0.54), while the proportion of infants requiring nasogastric tube feeding decreased from 84 to 8%. No infant had craniofacial surgery; one with syndromic RS required tracheostomy.

Conclusion

These longitudinal cohort data suggest that the Tübingen Palatal Plate as used here may alleviate upper airway obstruction by promoting mandibular growth.

Trial registration

N.A.

Current Trends in Surgical Airway Management of Neonates with Robin Sequence

Background

Robin sequence is defined by the clinical triad of micrognathia, glossoptosis, and upper airway obstruction, and is frequently associated with cleft palate and failure to thrive. Though the efficacy of certain surgical interventions to relieve airway obstruction has been well established, algorithms dictating decision making and perioperative protocols are poorly defined.

Methods

A 22-question survey was sent via e-mail to members of the American Cleft Palate-Craniofacial Association and International Society of Craniofacial Surgeons. Questions were related to surgeon experience in treating neonates with Robin sequence, and specific perioperative protocols.

Results

One hundred fifty-one responses were collected. Most respondents were surgeons practicing in North America(82.8%), in a university hospital setting (81.5%) and had completed a fellowship in pediatric plastic surgery or craniofacial surgery (76.2%). Preoperative protocols varied widely by years in training and location of practice. Although 78.8% of respondents always performed direct laryngoscopy, only 49.7% of respondents routinely obtained preoperative polysomnography. Mandibular distraction osteogenesis was the most common primary surgical airway intervention reported by 74.2%, with only 12.6% primarily utilizing tongue-lip adhesion. Slightly less than half of respondents ever performed tongue-lip adhesion. Operative selection was influenced by surgeon experience, with 80% of those in practice 0-5 years primarily utilizing mandibular distraction, compared with 56% of respondents in practice >15 years.

Conclusions

This study documents wide variations in preoperative, operative, and postoperative protocols for the surgical airway management of neonates with severe Robin sequence. These results underscore the need to acquire more objective data, to compare different protocols and outcome measures.

Mandibular Catch-Up Growth in Pierre Robin Sequence: A Systematic Review

Objective:

The concept of mandibular catch-up growth is often quoted in the literature regarding Pierre Robin sequence (PRS). We endeavored to perform a systematic review of whether the literature supports this concept.

Design:

Systematic review.

Interventions:

A PubMed-based systematic review of the English literature was performed of articles objectively measuring mandibular growth or position after nonoperative management of PRS.

Main Outcome Measures:

Rate and end point of mandibular length, ramus length, gonial angle, and maxillomandibular discrepancy.

Results:

The initial search delivered 607 English-language abstracts. Of these, 16 met inclusion criteria. Eight articles evaluating 143 patients followed longitudinal patient data and therefore allowed comparison of growth rates to controls. Ten articles evaluating 228 patients presented cross-sectional data and therefore could only evaluate a single time point. Two of the 8 longitudinal studies reported faster than normal growth of mandibular length in a significant portion of their cohort. Five of 8 reported equal growth rates. One of 16 studies reported that mandibular length of patients with PRS normalized compared to controls. Two of 16 studies reported no difference in maxillomandibular discrepancy between PRS and controls, whereas 10 reported a posteriorly displaced mandible relative to the maxilla in PRS. Significant differences in control groups, patients, and age existed between studies.

Conclusions:

While the concept of catch-up growth in PRS is often quoted, a minority of objective studies suggest increased mandibular growth rates in isolated PRS. Even fewer studies suggest that the maxillomandibular discrepancy in PRS completely resolves.

Characterization of the perinatal mandible growth pattern: preliminary results

PURPOSE

The fetal development of the mandible is nowadays quite understood, and it is already known that craniofacial growth reaches its highest rate during the first 5 years of postnatal life. However, there are very few data focusing on the perinatal period. Thus, the present article is addressing this concern by studying the mandible morphology and its evolution around the birth with a morphometric method.

METHODS

Thirty-one mandibles modelled in three dimensions from post-mortem CT-scans were analyzed. This sample was divided into two subgroups composed of, respectively, 15 fetuses (aged from 36 gestational weeks), and 16 infants (aged to 12 postnatal weeks). 17 distances, 3 angles, and 8 thicknesses were measured via the prior set of 14 landmarks, illustrating the whole mandible morphology.

RESULTS

Although this methodology may depend on the image reconstruction quality, its reliability was demonstrated with low variability in the results. It highlighted two distinct growth patterns around birth: fetuses mandibles do not significantly evolve during the perinatal period, whereas, from the second postnatal weeks, most of the measurements increased in a homogeneous tendency and in correlation with age.

CONCLUSIONS

The protocol developed in this study highlighted the morphologic evolution of the mandible around birth, identifying a different growth pattern from 2 postnatal weeks, probably because of the progressive activation of masticatory muscles and tongue. However, considering the small sample size, these results should be thorough, so identification and management of anatomic abnormalities could eventually be achieved.

Neonatal Mandibular Distraction Osteogenesis Reduces Cleft Palate Width and Lengthens Soft Palate, Influencing Palatoplasty in Patients With Pierre Robin Sequence

The aim of this study was to evaluate the influence of neonatal mandibular distraction osteogenesis (MDO) on cleft dimensions and on early palatoplasty outcomes in patients with Pierre Robin Sequence (PRS). In a prospective cohort study that enrolled 24 nonsyndromic patients with PRS, 12 submitted to the MDO group and 12 patients not treated (non-MDO group), the authors compared patients for cleft palate dimensions through 7 morphometric measurements at the moment of palatoplasty and for early palatoplasty outcomes. At palatoplasty, the MDO group presented a significant shorter distance between the posterior nasal spines (PNS-PNS, P < 0.001) and between uvular bases (UB-UB, P < 0.001), representing a reduction in cleft palate width. They also had significant soft palate lengthening represented by a larger distance between UB and retromolar space (UB-RM, P < 0.001) and UB and PNS (UB-PNS, P = 0.014). Their UB moved away from the posterior wall of the nasopharynx (UB-NPH, P < 0.001). The MDO group had a length of operative time significantly shorter (P < 0.001) and no early palatoplasty complications compared with the non-MDO group. In conclusion, MDO acted as an orthopedic procedure that reduced cleft palate width and elongated the soft palate in patients with PRS. These modifications enabled a reduction of around 11% in the length of operative time of palatoplasty (P < 0.001).

Pierre Robin sequence: Subdivision, data, theories, and treatment - Part 3: Prevailing controversial theories related to Pierre Robin sequence

Context:

The disorder currently accepted as Pierre Robin syndrome/anomaly/sequence (PRS) has been plagued by controversy ever since initially being described. Controversy exists not only about the appropriate terminology and etiopathogenesis of the disorder but also about its management. Therefore, clinical findings and treatment outcomes of a large database of 266 PRS cases were compared with the current state of knowledge in the scientific literature related to history, clinical description, diagnostic criteria, epidemiology, theories of oligohydramnios, mandibular catch-up growth, midfacial hyperplasia, and the early management.

Aim:

The aims of Part 3 debate the controversial biological theories relating to PRS.

Materials and Methods:

Oligo-/poly-hydramnios, mandibular catch-up growth, and midfacial hyperplasia, the three in the literature most prevailing theories related to PRS, have been compared and discussed with the findings provided by this large database of 266 Siebold-Robin sequence (SRS) and Fairbairn-Robin triad (FRT) cases.

Results:

History and clinical findings evaluated in this database refute the first two theories. Although manifold midfacial appearances were demonstrated in FRT cases, a third of all SRS cases presented with mid-facial hyperplasia.

Conclusion:

The three main biological theories regarding PRS could not be verified after thorough analysis of the database.

Analysis of the Relationship Between Micrognathia and Cleft Palate: A Systematic Review

Objective To gather data from relevant experimental and observational studies to determine the relationship between micrognathia and cleft palate. The goal is to raise awareness and motivate clinicians to consider the cause and effect relationship when confronted with patients with cleft palate, even if there is no clearly noticeable mandibular abnormality. Design Several electronic databases were systematically examined to find articles for this review, using search terms including "cleft palate," "micrognathia," "tongue," and "airway obstruction." PubMed was the source of all the articles chosen to be included. Exclusion criteria included case reports, articles focused on treatment options, and articles only tangentially related to cleft palate and/or micrognathia. Results A total of 930 articles were screened for relevance, and 82 articles were chosen for further analysis. Evidence gathered in this review includes a variety of etiological factors that are causative or associated with both micrognathia and cleft palate. Observational studies relating the two abnormalities are also included. Much of the included literature recognizes a cause-and-effect relationship between micrognathia and cleft palate. Conclusion On the basis of the published data, we suggest that micrognathia does induce cleft palate in humans and animals. With knowledge of this causative relationship, clinicians should consider the importance of gathering cephalometric data on the mandibles and tongues of patients presenting with isolated cleft palate to determine whether they have micrognathia as well. With more data, patterns may emerge that could give insight into the complex etiology of nonsyndromic cleft palate.

Polysomnographic results of prone versus supine positioning in micrognathia

BACKGROUND

Children with micrognathia commonly present with upper airway symptoms and are at risk for developing obstructive sleep apnea (OSA). Prone positioning is widely used as first-line management for micrognathic children with obstructive symptoms. The aim of the present study was to document the effect of positioning on oxygenation and upper airway obstruction as measured by polysomnography (PSG).

METHODS

Three children with micrognathia from two institutions underwent PSG in both the prone and supine position.

RESULTS

Patient ages were 1 week, 3 months, and 7 months. Supine obstructive apnea-hypopnea indices (oAHI) were severe for all 3 children, with a mean of 21.9 events/hour (range 16.8 to 26.3). In the prone position, the oAHI significantly improved in 2 of 3 children, with a mean of 5.1 events/hour (range 0.3 to 10.3). The frequency of central apnea events increased in 1 child following supine positioning. Nadir oxygen saturation improved in 2 of 3 children and remained within normal limits in the third.

CONCLUSIONS

This is the first report of the effect of positioning on changes in PSG indices of micrognathic children. Improvement in obstructive PSG indices occurred with prone positioning, though OSA persisted in 2 of 3 children. The effect of positioning on central apnea was unclear. In light of these findings, we recommend that routine PSG be considered in micrognathic children undergoing prone positioning for definitive therapy of upper airway obstruction.

Predictive value of weight gain and airway obstruction in isolated Robin sequence

OBJECTIVE

Treatment of airway obstruction and feeding difficulties among newborns with isolated Robin sequence is challenging. The lack of clear guidelines may lead to prolonged hospital stays and delays in treatment. Appropriate risk stratification can facilitate treatment planning. We aim to identify factors that prognosticate prolonged hospital stay in children with isolated Robin sequence.

SETTING

We used a retrospective multivariate analysis of 46 patients admitted with isolated Robin sequence at the Hospital for Sick Children, in Toronto, between 2000 and 2007. During the initial 4 weeks following admission, data regarding duration of hospital stay, management of airway obstruction, respiratory rate, management of feeding difficulties, and reflux therapy were collected.

RESULTS

Correlation between length of hospital stay, airway management, and weight gain during the initial 4 weeks was noted. No correlation was found between length of hospital stay and respiratory rate, supplemental oxygen requirement, or reflux therapy.

CONCLUSIONS

Risk stratification is possible in children with isolated Robin sequence. Delayed weight gain in Robin sequence correlates with the degree of airway obstruction. The need for a nasopharyngeal tube and weight gain during the initial 4 weeks of life in newborns with Robin sequence reliably predict length of hospital stay. These prognosticators should contribute to parent and physician expectations, as well as assist in treatment and discharge planning.

Anesthetic implications of infants with mandibular hypoplasia treated with mandibular distraction osteogenesis

OBJECTIVES

To document the incidence of difficult intubation following mandibular distraction osteogenesis (MDO) in children with severe mandibular hypoplasia.

BACKGROUND

Syndromes associated with significant mandibular hypoplasia, especially Pierre Robin sequence, provide a challenge in airway management both in and out of the operating room. Mandibular advancement using mandibular distraction osteogenesis devices has been used in infants in an attempt to reduce the incidence of acute life-threatening airway obstruction. Whether MDO also reduces the incidence of difficult intubation has not been adequately described.

METHODS

A retrospective chart review of 51 infants with upper airway obstruction secondary to mandibular hypoplasia who required MDO between January 2002 and 2012. The primary outcome was the incidence of difficult or failed intubation. Secondary outcomes were the relationship between syndrome type and the incidence of difficult intubation.

RESULTS

Fifty-one PRS infants were identified. Twenty-eight patients had isolated PRS, six had syndromic PRS, seven had Treacher Collins syndrome, and 10 had another coexisting syndrome. Prior to mandibular distraction osteogenesis (MDO), the incidence of difficult intubation was 71%, with the highest incidence in patients with Treacher Collins syndrome (100%), sPRS syndrome (100%), and PRS (65%). Following MDO, the incidence of difficult intubation was 8.3%. The difference was statistically significant for all patients (Kruskal-Wallis rank test P = 0.0001) those with isolated PRS (P = 0.0001), syndromic PRS (P = 0.0023), and other syndromes (P = 0.0002), but not for Treacher Collins syndrome (P = 0.21). Three patients had pre existing tracheostomies.

CONCLUSIONS

In a select group of infants with severe upper airway obstruction who have failed nonsurgical airway interventions, mandibular distraction osteogenesis reduces the incidence of difficult mask ventilation and difficult intubation. We were not able to compare the improvement in airway management to a comparable group of PRS infants who did not undergo surgical intervention. The improvement in laryngeal view was most marked for infants with isolated PRS but no significant benefit was demonstrated in infants with TCS.

Facial Profile Evaluation of Isolated Pierre Robin Sequence

Objective

To evaluate numerically the facial profile of children with isolated Pierre Robin sequence (PRS) and to compare them with a control group that has no pathologies and exhibits regular and balanced facial growth, with no skeletal alterations.

Patients

Eighty-three children aged 5 to 10 years (PRS group, n = 60; control group, n = 23) were selected.

Setting

Hospital for Rehabilitation of Craniofacial Anomalies, University of Sao Paulo (HRAC-USP). Children from the control group were taken from the program of Interceptive Orthodontics at HRAC-USP.

Design

Angular and ratio analyses of the facial profiles in both groups were realized through digital photographs. The PRS group was subdivided into two groups—complete and incomplete—according to the sagittal extension of the cleft palate, to investigate the possible influence of cleft extension on the face.

Results

The facial convexity angle and the facial inferior third angle were considerably higher in the PRS groups than in the control group and were not significantly different between PRS groups. Nasolabial angle did not differ between groups.

Conclusion

The facial profile was more convex in individuals with PRS than in those with regular facial growth and with no pathology. The mandible was responsible for the convexity of the profile in PRS because of its lack off anterior projection. An important relationship between the extension of the cleft palate and alterations in facial profile in PRS was not observed.

Early postnatal development of the mandibular permanent first molar in infants with isolated cleft palate

BACKGROUND

Based on measurements on dental casts, smaller permanent teeth in children with cleft palate have previously been reported in the literature; however, the early maturation of teeth and the size of the follicles and crowns have not been investigated.

HYPOTHESIS

The maturation of the mandibular permanent first molar (M1(inf)) is delayed, and the mesiodistal diameters of the follicle and crown of M1(inf), respectively, are reduced in children with isolated cleft palate (ICP).

DESIGN

Retrospective, longitudinal. Cephalometric X-rays were available for 2 and 22 months old children with clefts (64 children with ICP, and a control group of 38 children with unilateral incomplete cleft lip). The width of the follicle and the crown of M1(inf), and the maturation of M1(inf) were assessed. Intra-observer error was acceptable.

RESULTS

M1(inf) maturation was delayed in children with ICP at both 2 and 22 months of age. The mesiodistal diameter of the crown of M1(inf) in the ICP group was reduced. Thus, the two hypotheses could not be refuted.

CONCLUSIONS

Children with ICP showed smaller dimensions of the M1(inf) , and in addition, the maturation of M1(inf) was delayed.

Obstructive sleep apnea in infants

Obstructive sleep apnea in infants has a distinctive pathophysiology, natural history, and treatment compared with that of older children and adults. Infants have both anatomical and physiological predispositions toward airway obstruction and gas exchange abnormalities; including a superiorly placed larynx, increased chest wall compliance, ventilation-perfusion mismatching, and ventilatory control instability. Congenital abnormalities of the airway, such as laryngomalacia, hemangiomas, pyriform aperture stenosis, choanal atresia, and laryngeal webs, may also have adverse effects on airway patency. Additional exacerbating factors predisposing infants toward airway collapse include neck flexion, airway secretions, gastroesophageal reflux, and sleep deprivation. Obstructive sleep apnea in infants has been associated with failure to thrive, behavioral deficits, and sudden infant death. The proper interpretation of infant polysomnography requires an understanding of normative data related to gestation and postconceptual age for apnea, arousal, and oxygenation. Direct visualization of the upper airway is an important diagnostic modality in infants with obstructive apnea. Treatment options for infant obstructive sleep apnea are predicated on the underlying etiology, including supraglottoplasty for severe laryngomalacia, mandibular distraction for micrognathia, tonsillectomy and/or adenoidectomy, choanal atresia repair, and/or treatment of gastroesophageal reflux.

The occurrence of velopharyngeal insufficiency in Pierre Robin Sequence patients

OBJECTIVE

Children born with Pierre-Robin Sequence (PRS) have cleft palate, micrognathia, and macroglossia. After the repair of the cleft palate, velopharyngeal insufficiency (VPI) can occur in a subset of patients. We hypothesize that the need for the surgical correction of VPI in PRS children is no different than cleft palate only (CPO) patients.

METHODS

A retrospective study of 21 children with non-syndromic PRS who were matched to 42 non-syndromic, CPO controls for age and sex. We reviewed incidence of VPI, the need for secondary speech surgery, and speech outcomes post-operatively.

RESULTS

Secondary surgery to correct VPI was necessary in 3 of 21 (14.29%) PRS patients (2 Pharyngeal Flaps, 1 Z-plasty), vs. 10 of 42 (23.81%) CPO (9 Pharyngeal Flaps, 1 Z-plasty) controls. Mean age for VPI surgery for PRS vs. controls: 5.33 vs. 6.41 years, respectively. For final speech outcomes, 73.68% of PRS vs. 71.88% of controls showed no evidence of hypernasality, 89.47% of PRS patients vs. 93.75% of controls showed no evidence of hyponasality, and 76.47% of PRS patients vs. 78.13% of controls had normal velopharyngeal competence (p>0.90 for all three measures).

CONCLUSION

Our findings suggest that children born with a Pierre-Robin Sequence do not have a higher rate of post-operative VPI after cleft palate repair and are no more likely to require additional surgical intervention.

Neonates with Tongue-Based Airway Obstruction

Objective. In this systematic review, the authors summarize the current evidence in the literature regarding diagnosis, treatment, and long-term outcomes in neonates with tongue-based airway obstruction (TBAO) and assess the level of evidence of included studies.

Data Sources. The terms Pierre Robin syndrome/sequence, micrognathia, retrognathia, and cleft palate were combined with airway obstruction, treatment, tongue-lip plication, and osteogenesis distraction to perform an Ovid literature search, yielding 341 references. The authors excluded references containing patients with isolated choanal/nasal obstruction, patients older than 12 months, and expert opinion papers, yielding 126 articles.

Review Methods. The authors searched 3 electronic databases and reference lists of existing reviews from 1980 to October 2010 for articles pertaining to the diagnosis, treatment, and outcomes of TBAO. Reviewers assigned a level of evidence score based on Oxford’s Centre for Evidence Based Medicine scoring system and recorded relevant information.

Results. Most studies were case studies and single-center findings. The lack of standardization of diagnostic and treatment protocols and the heterogeneity of cohorts both within and between studies precluded a meta-analysis. There was little evidence beyond expert opinion and single-center evaluation regarding diagnosis, treatment, and long-term outcomes of neonates with TBAO.

Conclusions. The variability in the phenotype of the cohorts studied and the absence of standardized indications for intervention preclude deriving any definitive conclusions regarding diagnostic tools to evaluate this patient population, treatment choices, or long-term outcomes. A coordinated multicenter study with a standardized diagnostic and treatment algorithm is recommended to develop evidence for the diagnosis and treatment of neonates with TBAO.

Characterization of obstructive sleep apnea before and after tongue-lip adhesion in children with micrognathia

OBJECTIVES

To characterize airway obstruction before and after tongue-lip adhesion in children with micrognathia using polysomnography.

DESIGN

Retrospective pilot case series.

PARTICIPANTS AND METHODS

Evaluation of all children with micrognathia who underwent tongue-lip adhesion and polysomnography before and after surgery from 2002 to 2007 (N  =  8).

RESULTS

Eight children met inclusion criteria; six were girls. The mean interval between polysomnography and tongue-lip adhesion was 6 days (range, 2 to 13 days) preoperatively and 17 days (range, 5 to 32 days) postoperatively. Severe obstructive sleep apnea was identified in seven of eight (88%) children, with a mean preoperative obstructive apnea hypopnea index of 52.6 events per hour (range, 7.1 to 85.7 events per hour). None had significant central sleep apneas (>5 per hour). Tongue-lip adhesion resulted in a mean decrease of 34.5 events per hour (range, -65.8 to 71.6 events per hour). After tongue-lip adhesion, seven of eight (87.5%) patients had an improved obstructive apnea hypopnea index, with resolution of obstructive sleep apnea in one child and improvement to mild (two) and moderate (two) obstructive sleep apnea in four others. Only one child had an obstructive apnea hypopnea index that increased after tongue-lip adhesion. Peak end-tidal pCO(2) measurements were elevated in all eight children before surgery at a mean of 60 mm Hg (range, 52 to 76 mm Hg) that improved to 51 mm Hg (range, 45 to 59 mm Hg), with normal peak levels in four children. Oxygen saturation nadir improved from 73% (range, 58% to 81%) to 82% (range, 65% to 94%).

CONCLUSIONS

Tongue-lip adhesion may be performed in micrognathic infants to alleviate airway obstruction. Polysomnographic evaluation in this pilot study before and after surgery suggests that tongue-lip adhesion usually improves obstructive sleep apnea, but only 38% had complete resolution. Future studies of tongue-lip adhesion efficacy should include polysomnographic evaluation.

Facial skeletal morphology in growing children with Pierre Robin sequence

OBJECTIVE

The purpose was to compare the jaw size, jaw relationship, and facial proportions of children with nonsyndromic Pierre Robin sequence with children with nonsyndromic or isolated cleft palate.

DESIGN

This is a retrospective cohort study comparing radiographic findings in children with Pierre Robin sequence or isolated cleft palate at two time intervals: ages 4 to 7 years (T1) and ages 10 to 13 years (T2). Linear and angular measurements were obtained using cephalograms; the cephalometric values were compared with unpaired t tests, assuming unequal variances.

SETTING

The study was conducted at the Center for Craniofacial Anomalies at the University of California, San Francisco.

PATIENTS

The sample included 13 children with Pierre Robin sequence and 14 children with isolated cleft palate who were followed at University of California, San Francisco, craniofacial anomalies clinic during the period from 1971 to 2007 and met the inclusion criteria.

MAIN OUTCOME MEASURES

The outcome measures were mandibular length, maxillary length, and sagittal jaw relationship in Pierre Robin sequence and isolated cleft palate children at T1 and T2.

RESULTS

During early childhood (T1: 4 to 7 years), mandibular length (Co-Gn) was similar in both Pierre Robin sequence and isolated cleft palate groups, as was the maxillary length (Co-A). In older children (T2: 10 to 13 years) mandibular length was significantly shorter in the Pierre Robin sequence group compared with the isolated cleft palate group (difference  =  10.9 mm, p  =  .009). Maxillary length in Pierre Robin sequence and isolated cleft palate groups was similar at T2 but significantly shorter in comparison to age-matched norms with a difference of 14.5 mm (p  =  .037) for Pierre Robin sequence and 12.4 mm (p  =  .045) for isolated cleft palate. Children with Pierre Robin sequence did not show a sagittal jaw discrepancy due to a proportionate deficiency in maxillary and mandibular length; whereas, children with isolated cleft palate showed a greater sagittal jaw discrepancy due to normal mandibular length and deficiency in maxillary length.

CONCLUSION

Our study confirms the findings of some previous studies that suggest that children with nonsyndromic Pierre Robin sequence have a proportionate retrusion of the maxilla and mandible, resulting in a convex facial profile by early adolescence.

Three-dimensional assessment of facial development in children with Pierre Robin sequence

Newborns with Pierre Robin sequence (PRS) have mandibular hypoplasia, glossoptosis, and possibly cleft palate. Their facial appearance is characteristic. The further facial development is controversial. The aim of this study was to analyze the facial development of children with PRS.In a prospective, cross-sectional study, 344 healthy children and 37 children with PRS and cleft palate younger than 8 years were scanned three-dimensionally. Twenty-one standard anthropometric landmarks were identified, and the images were superimposed. Growth curves for normal facial development were calculated. The facial morphology of children with PRS was compared with that of healthy children.The facial growth of children with PRS in the transversal and vertical direction was normal. In the sagittal direction, the mandibular deficit was confirmed. Except for the orbital landmarks and nasion, all landmarks of the midface demonstrated a significant sagittal deficit. This difference to healthy children remained constant for all ages.Our study cannot support the theory of mandibular catch-up growth. The sagittal deficit of the midface could be observed in all ages. This indicates that children with PRS have a very early, severe, and persistent underdevelopment of this part of the face. We conclude that this disturbance must be addressed in early childhood with orthodontic and speech therapy.

Developmental aspects of the upper airway: report from an NHLBI Workshop, March 5-6, 2009

The upper airway serves three important functions: respiration, swallowing, and speech. During development it undergoes significant structural and functional changes that affect its size, shape, and mechanical properties. Abnormalities of the upper airway require prompt attention, because these often alter ventilatory patterns and gas exchange, particularly during sleep when upper airway motor tone and ventilatory drive are diminished. Recognizing the relationship of early life events to lung health and disease, the National Heart, Lung, and Blood Institute (NHLBI), with cofunding from the Office of Rare Diseases (ORD), convened a workshop of extramural experts, from many disciplines. The objective of the workshop was: (1) to review the state of science in pediatric upper airway disorders; (2) to make recommendations to the Institute to fill knowledge gaps; (3) to prioritize new research directions; and (4) to capitalize on scientific opportunities. This report provides recommendations that could facilitate translation of basic research findings into practice to better diagnose, treat, and prevent airway compromise in children.

Abnormal mandibular growth and the condylar cartilage

Deviations in the growth of the mandibular condyle can affect both the functional occlusion and the aesthetic appearance of the face. The reasons for these growth deviations are numerous and often entail complex sequences of malfunction at the cellular level. The aim of this review is to summarize recent progress in the understanding of pathological alterations occurring during childhood and adolescence that affect the temporomandibular joint (TMJ) and, hence, result in disorders of mandibular growth. Pathological conditions taken into account are subdivided into (1) congenital malformations with associated growth disorders, (2) primary growth disorders, and (3) acquired diseases or trauma with associated growth disorders. Among the congenital malformations, hemifacial microsomia (HFM) appears to be the principal syndrome entailing severe growth disturbances, whereas growth abnormalities occurring in conjunction with other craniofacial dysplasias seem far less prominent than could be anticipated based on their often disfiguring nature. Hemimandibular hyperplasia and elongation undoubtedly constitute the most obscure conditions that are associated with prominent, often unilateral, abnormalities of condylar, and mandibular growth. Finally, disturbances of mandibular growth as a result of juvenile idiopathic arthritis (JIA) and condylar fractures seem to be direct consequences of inflammatory and/or mechanical damage to the condylar cartilage.