1173 Airway and Breathing Problems in Pierre Robin Sequence: A Systematic Review Protocol

Aim

The primary aim is to systematically review the specific airway and/or breathing problems which have been reported in Pierre Robin Sequence (PRS). Secondary aims are to understand the prevalence and severity of these airway and breathing problems, and options for screening, assessment, and monitoring.

Method

A search strategy will be designed to search the following databases: MEDLINE, Embase, Web of Science, and the Cochrane Central Register of Controlled Trials(CENTRAL) including a grey literature search, to identify publications on airway and/or breathing problems in Pierre Robin Sequence patients. Airway or breathing problems to be included are defined upper airway conditions (e.g., sleep apnoea) or clinically or objectively defined airway/breathing problems (e.g., increased respiratory rate, polysomnography). Screening will exclude non-English articles, abstracts, letters, editorials, expert opinions and breathing problems not anatomically related to craniofacial underdevelopment.

Results

This systematic review has been successfully registered on the PROSPERO International Prospective Register of Systematic Reviews (CRD42020210572)

Conclusions

PRS is a rare craniofacial condition which presents at birth, consisting of micrognathia, glossoptosis and airway problems, and is usually, but not always, associated with a cleft palate. There is no consensus on the type of airway problems that affect patients with PRS. The findings of this systematic review will help to develop a consensus on the airway and breathing problems in PRS and options for assessment and monitoring of the airway and breathing problem. This data may also contribute to development of a standardized guideline for management of airway and breathing problems in PRS.

The governance of overseas surgical collaborations - BFIRST/BSSH

Clinical governance is the structured approach to maintaining and improving the quality of patient care and is a vital part of global surgery. BFIRST and BSSH closely collaborate with local doctors on a number of overseas projects, seeking to strengthen and develop local knowledge and skills, aiming for an independent local practice in reconstructive and upper limb surgery. Thoughts on essential requirements, improvements and pitfalls in the ethical approach to global collaboratives are presented.

Disruption of FOXF2 as a Likely Cause of Absent Uvula in an Egyptian Family

This study investigated the genetic basis of an unusual autosomal dominant phenotype characterized by familial absent uvula, with a short posterior border of the soft palate, abnormal tonsillar pillars, and velopharyngeal insufficiency. Cytogenetic analysis and single-nucleotide polymorphism-based linkage analysis were investigated in a 4-generation family with 8 affected individuals. Whole exome sequencing data were overlaid, and segregation analysis identified a single missense variant, p.Q433P in the FOXF2 transcription factor, that fully segregated with the phenotype. This was found to be in linkage disequilibrium with a small 6p25.3 tandem duplication affecting FOXC1 and GMDS. Notably, the copy number imbalances of this region are commonly associated with pathologies that are not present in this family. Bioinformatic predictions with luciferase reporter studies of the FOXF2 missense variant indicated a negative impact, affecting both protein stability and transcriptional activation. Foxf 2 is expressed in the posterior mouse palate, and knockout animals develop an overt cleft palate. Since mice naturally lack the structural equivalent of the uvula, we demonstrated FOXF2 expression in the developing human uvula. Decipher also records 2 individuals with hypoplastic or bifid uvulae with copy number variants affecting FOXF2. Nevertheless, given cosegregation with the 6p25.3 duplications, we cannot rule out a combined effect of these gains and the missense variant on FOXF2 function, which may account for the rare palate phenotype observed.

Delayed detection of cleft palate: an audit of newborn examination

AIMS

To identify prevalence of delayed detection of cleft palate, and associated factors that could lead to improved identification at neonatal clinical examination.

METHODS

Audit of hospital notes, parental questionnaire incorporating open ended questions, and telephone questionnaire of junior doctors in the referring hospitals incorporating fixed choice questions.

RESULTS

Of 344 cleft palate patients without cleft lip or submucous cleft palate, the day the cleft was detected was recorded in 92%. Delayed detection, after the first day, was 28% overall, distributed as 37% with isolated cleft palate and 23% with syndromic cleft palate. Narrow V shaped clefts were more likely to be delayed in detection compared with broad U shaped clefts, as were soft palate clefts compared with hard palate clefts. Five with isolated cleft palates were not detected until after the first year. Babies born at home were unlikely to be detected on day 1. Symptoms were significantly increased in the delayed detection group for feeding problems and nasal regurgitation. A telephone questionnaire of trainee paediatricians in referring units revealed that digital examination was more commonly practised than visual inspection, and few recalled receiving specific instruction on examination of the palate.

CONCLUSION

Delayed detection of cleft palate was not uncommon, and the features of those more likely to be missed suggested digital examination was related. Trainee doctors and midwives should be instructed to inspect visually using a light and tongue depressor, then digitally if submucous cleft palate is suspected.

Velopharyngeal insufficiency following adenoidectomy1

Velopharyngeal insufficiency (VPI) is a well recognized but rare complication of adenoidectomy. Twenty children with this condition were seen and assessed at Great Ormond Street Hospital between 1993 and 2000. The commonest aetiology was occult submucous cleft palate (n = 5) but there was a wide range of other causes. Two children with severe behavioural disorders and normal palates developed mild symptoms, an aetiology not previously reported. Only two children had a classical submucous cleft palate. Nine children required surgical intervention and three revision procedures. Of the 15 treated children for whom follow-up data was available, 13 regained normal or near-normal speech. Many cases of postadenoidectomy VPI was not foreseeable. Following referral to a specialist cleft unit, normal or near-normal speech can be achieved in the majority with a combination of surgery and speech therapy.

Evaluation of hearing thresholds in 3-month-old children with a cleft palate: the basis for a selective policy for ventilation tube insertion at time of palate repair

Hearing thresholds in children with a cleft palate prior to cleft palate repair are not widely documented, and audiological criteria for short-term ventilation tube insertion do not exist. The aims of this prospective study are to estimate hearing thresholds in 40 children with a cleft palate by 3-month developmental age with auditory brainstem responses (ABRs) under natural sleep and to estimate a hearing threshold guideline for short-term ventilation tube insertion. Our results show a wide range of air conduction hearing thresholds using click ABRs (2-4 Hz), which ranged from 25 to 102 dBnHL in the left ear and from 25 to 80 dBnHL in the right ear with means of 53 and 49 and standard deviations of 17 and 13 respectively. The bone conduction thresholds ranged from 0 to 55 dBnHL with a mean of 26 and a standard deviation of 13. Eighty-three per cent of children had flat, type B, on high-frequency tympanograms, indicative of middle ear effusion. Thirty per cent of the infants had a cleft palate associated with a known syndrome. Currently, it is the authors' practice to use short-term ventilation tubes on a selective basis at the time of cleft palate repair when there is a conductive hearing loss of more than 55 dBnHL in the better ear as determined by ABR with type B high-frequency tympanograms. This threshold level takes into account electrophysiological and auditory pathway maturation discrepancies. With this as the guideline, between 28% and 35% of the children in this study would be eligible for surgery. This criterion still requires further validation.

Are we ready to predict speech development from babble in cleft lip and palate children?

The speech development of nine children with cleft lip/palate was followed longitudinally from nine months to three years of age. The results indicate speech sound development closer to the non-cleft population than previous studies. Nasal fricatives previously not extensively described in the literature may be an experimental stage of developmental babble, which spontaneously reduce. The study has added to the evidence-base for practice in one cleft unit. It may be useful to channel resources at our centre to children who at nine months may be more at risk, i.e. children with bilateral clefts and known developmental delay.

Lateral videofluoroscopy: a modification to aid in velopharyngeal assessment and measurement

To overcome the difficulty of obtaining adequate videofluoroscopic images with small children because of lack of cooperation and their inability to keep their heads still and correctly rotated, a 3D View-Master was attached to the x-ray table. Its use greatly increased the ability to conduct lateral videofluoroscopies of small children by improving patient compliance, stabilizing rotation and reducing unwanted head movement, and by standardizing magnification.

Heterotopic brain presenting as a cystic mass of the palate

We report a case of heterotopic brain which presented as a cystic mass in the palate and which clinically was thought to be a cystic hygroma. Histologically, there was a remarkable proliferation of choroid plexus-like structures which we believe to have been responsible for the production of cerebrospinal fluid. We believe heterotopic brain to result from early displacement of multipotential cells and that the presence of cerebrospinal fluid within extracranial brain tissue does not imply an intracranial communication.