Alpelisib for the treatment of PIK3CA-related head and neck lymphatic malformations and overgrowth.

PURPOSE: PIK3CA-related overgrowth spectrum (PROS) conditions of the head and neck are treatment challenges. Traditionally, these conditions require multiple invasive interventions, with incomplete malformation removal, disfigurement, and possible dysfunction. Use of the PI3K inhibitor alpelisib, previously shown to be effective in PROS, has not been reported in PIK3CA-associated head and neck lymphatic malformations (HNLMs) or facial infiltrating lipomatosis (FIL). We describe prospective treatment of 5 children with PIK3CA-associated HNLMs or head and neck FIL with alpelisib monotherapy. METHODS: A total of 5 children with PIK3CA-associated HNLMs (n = 4) or FIL (n = 1) received alpelisib monotherapy (aged 2-12 years). Treatment response was determined by parental report, clinical evaluation, diary/questionnaire, and standardized clinical photography, measuring facial volume through 3-dimensional photos and magnetic resonance imaging. RESULTS: All participants had reduction in the size of lesion, and all had improvement or resolution of malformation inflammation/pain/bleeding. Common invasive therapy was avoided (ie, tracheotomy). After 6 or more months of alpelisib therapy, facial volume was reduced (range 1%-20%) and magnetic resonance imaging anomaly volume (range 0%-23%) were reduced, and there was improvement in swallowing, upper airway patency, and speech clarity. CONCLUSION: Individuals with head and neck PROS treated with alpelisib had decreased malformation size and locoregional overgrowth, improved function and symptoms, and fewer invasive procedures.

Cell-free DNA as a diagnostic analyte for molecular diagnosis of vascular malformations.

PURPOSE: Vascular malformations (VM) are primarily caused by somatic activating pathogenic variants in oncogenes. Targeted pharmacotherapies are emerging but require molecular diagnosis. Since variants are currently only detected in malformation tissue, patients may be ineligible for clinical trials prior to surgery. We hypothesized that cell-free DNA (cfDNA) could provide molecular diagnoses for patients with isolated VM. METHODS: cfDNA was isolated from plasma or cyst fluid from patients with arteriovenous malformations (AVM), venous malformations (VeM), or lymphatic malformations (LM), and assayed for known pathogenic variants using droplet digital polymerase chain reaction (ddPCR). Cyst fluid cfDNA from an independent cohort of LM patients was prospectively screened for variants using a multiplex ddPCR assay. RESULTS: Variants were detected in plasma cfDNA in patients with AVM (2/8) and VeM (1/3). Variants were detected in cyst fluid cfDNA (7/7) but not plasma (0/26) in LM patients. Prospective testing of cyst fluid cfDNA with multiplex ddPCR identified variants in LM patients who had never undergone surgery (4/5). CONCLUSION: Variants were detected in plasma from AVM and VeM patients, and in cyst fluid from patients with LM. These data support investigation of cfDNA-based molecular diagnostics for VM patients, which may provide opportunities to initiate targeted pharmacotherapies without prior surgery.

Pathogenic variant in EPHB4 results in central conducting lymphatic anomaly.

Central conducting lymphatic anomaly (CCLA) is one of the complex lymphatic anomalies characterized by dilated lymphatic channels, lymphatic channel dysmotility and distal obstruction affecting lymphatic drainage. We performed whole exome sequencing (WES) of DNA from a four-generation pedigree and examined the consequences of the variant by transfection of mammalian cells and morpholino and rescue studies in zebrafish. WES revealed a heterozygous mutation in EPHB4 (RefSeq NM_004444.4; c.2334 + 1G>C) and RNA-Seq demonstrated that the EPHB4 mutation destroys the normal donor site, which leads to the use of a cryptic splice donor that results in retention of the intervening 12-bp intron sequence. Transient co-expression of the wild-type and mutant EPHB4 proteins showed reduced phosphorylation of tyrosine, consistent with a loss-of-function effect. Zebrafish ephb4a morpholino resulted in vessel misbranching and deformities in the lymphatic vessel development, indicative of possible differentiation defects in lymphatic vessels, mimicking the lymphatic presentations of the patients. Immunoblot analysis using zebrafish lysates demonstrated over-activation of mTORC1 as a consequence of reduced EPHB4 signaling. Strikingly, drugs that inhibit mTOR signaling or RAS-MAPK signaling effectively rescued the misbranching phenotype in a comparable manner. Moreover, knock-in of EPHB4 mutation in HEK293T cells also induced mTORC1 activity. Our data demonstrate the pathogenicity of the identified EPHB4 mutation as a novel cause of CCLA and suggesting that ERK inhibitors may have therapeutic benefits in such patients with complex lymphatic anomalies.

Catel-Manzke syndrome without Manzke dysostosis.

Catel-Manzke syndrome is characterized by hand anomalies, Robin sequence, cardiac defects, joint hyperextensibility, and characteristic facial features. Approximately 40 patients with Catel-Manzke have been reported, all with the pathognomonic bilateral or unilateral hyperphalangy caused by an accessory bone between the second metacarpal and proximal phalanx known as Manzke dysostosis. Here we present the first case of molecularly confirmed Catel-Manzke syndrome with Robin sequence but without Manzke dysostosis.

Activating variants in PDGFRB result in a spectrum of disorders responsive to imatinib monotherapy.

More than 50 individuals with activating variants in the receptor tyrosine kinase PDGFRB have been reported, separated based on clinical features into solitary myofibromas, infantile myofibromatosis, Penttinen syndrome with premature aging and osteopenia, Kosaki overgrowth syndrome, and fusiform aneurysms. Despite their descriptions as distinct clinical entities, review of previous reports demonstrates substantial phenotypic overlap. We present a case series of 12 patients with activating variants in PDGFRB and review of the literature. We describe five patients with PDGFRB activating variants whose clinical features overlap multiple diagnostic entities. Seven additional patients from a large family had variable expressivity and late-onset disease, including adult onset features and two individuals with sudden death. Three patients were treated with imatinib and had robust and rapid response, including the first two reported infants with multicentric myofibromas treated with imatinib monotherapy and one with a recurrent p.Val665Ala (Penttinen) variant. Along with previously reported individuals, our cohort suggests infants and young children had few abnormal features, while older individuals had multiple additional features, several of which appeared to worsen with advancing age. Our analysis supports a diagnostic entity of a spectrum disorders due to activating variants in PDGFRB. Differences in reported phenotypes can be dramatic and correlate with advancing age, genotype, and to mosaicism in some individuals.

Lymphatic and other vascular malformative/overgrowth disorders are caused by somatic mutations in PIK3CA.

OBJECTIVES: To test the hypothesis that somatic phosphatidylinositol-4,5-bisphospate 3-kinase, catalytic subunit alpha (PIK3CA) mutations would be found in patients with more common disorders including isolated lymphatic malformation (LM) and Klippel-Trenaunay syndrome (KTS). STUDY DESIGN: We used next generation sequencing, droplet digital polymerase chain reaction, and single molecule molecular inversion probes to search for somatic PIK3CA mutations in affected tissue from patients seen at Boston Children's Hospital who had an isolated LM (n = 17), KTS (n = 21), fibro-adipose vascular anomaly (n = 8), or congenital lipomatous overgrowth with vascular, epidermal, and skeletal anomalies syndrome (n = 33), the disorder for which we first identified somatic PIK3CA mutations. We also screened 5 of the more common PIK3CA mutations in a second cohort of patients with LM (n = 31) from Seattle Children's Hospital. RESULTS: Most individuals from Boston Children's Hospital who had isolated LM (16/17) or LM as part of a syndrome, such as KTS (19/21), fibro-adipose vascular anomaly (5/8), and congenital lipomatous overgrowth with vascular, epidermal, and skeletal anomalies syndrome (31/33) were somatic mosaic for PIK3CA mutations, with 5 specific PIK3CA mutations accounting for ∼ 80% of cases. Seventy-four percent of patients with LM from Seattle Children's Hospital also were somatic mosaic for 1 of 5 specific PIK3CA mutations. Many affected tissue specimens from both cohorts contained fewer than 10% mutant cells. CONCLUSIONS: Somatic PIK3CA mutations are the most common cause of isolated LMs and disorders in which LM is a component feature. Five PIK3CA mutations account for most cases. The search for causal mutations requires sampling of affected tissues and techniques that are capable of detecting low-level somatic mosaicism because the abundance of mutant cells in a malformed tissue can be low.

Delaying Invasive Treatment in Unilateral Head and Neck Lymphatic Malformation Improves Outcomes.

OBJECTIVES: Large (De Serres stage [IV-V]) head and neck lymphatic malformations (HNLMs) often have multiple, high-risk, invasive treatments (ITs) to address functional compromise. Logically reducing HNLM ITs should reduce treatment risk. We tested whether delaying HNLM ITs reduces total IT number. MATERIALS: Consecutive HNLM patients (n = 199) between 2010 and 2017, aged 0-18 years. METHODS: ITs (surgery or sclerotherapy) were offered for persistent or dysfunction causing HNLMs. Treatment effectiveness categorized by IT number: optimal (0-1), acceptable (2-5), or suboptimal (>5). Clinical data were summarized, and outcome associations tested (χ2 ). Relative risk (RR) with a Poisson working model tested whether HNLM observation or IT delay (>6 months post-diagnosis) predicts treatment success (i.e., ≤1 IT). RESULTS: Median age at HNLM diagnosis was 1.3 months (interquartile range [IQR] 0-45 m) with 107/199(54%) male. HNLM were stage I-III (174 [88%]), IV-V (25 [13%]). Initial treatment was observation (70 [35%]), invasive (129 [65%]). Treatment outcomes were optimal (137 [69%]), acceptable (36 [18%]), and suboptimal (26 [13%]). Suboptimal outcome associations: EXIT procedure, stage IV-V, oral location, and tracheotomy (p < 0.001). Stage I-III HNLMs were initially observed compared with stage I-III having ITs within 6 months of HNLM diagnosis, had a 82% lower relative treatment failure risk ([i.e., >1 IT], RR = 0.09, 95% CI 0.02-0.36, p < 0.001). Stage I-III HNLMs with non-delayed ITs had reduced treatment failure risk compared with IV-V (RR = 0.47, 95% CI 0.33-0.66, p < 0.001). CONCLUSION: Observation and delayed IT in stage I-III HNLM ("Grade 1") is safe and reduces IT (i.e., ≤1 IT). Stage IV-V HNLMs ("Grade 2") with early IT have a greater risk of multiple ITs. LEVEL OF EVIDENCE: 4 Laryngoscope, 133:956-962, 2023.

Centers of Excellence: If We Build It, Will They Come?

Pediatric surgeons have been pursuing high quality, affordable care or value-based care for over 50 years. One approach to streamlining the clinical care for a complex problem was the development of a center of excellence (COE). The concept of COE focuses on a shared vision of providing high quality care through a multidisciplinary approach. The goal is to improve diagnostic accuracy as well as therapeutic outcomes using focused expertise within a group. COEs are often resource intensive before becoming fiscally viable and therefore require initial support from hospital leadership. This review discusses the key steps to consider before building a COE, strategies to help build one, and how to keep one successful as defined by quality, accessibility, equity, training, and maintaining teams within the group.

Sphincter Pharyngoplasty for Velopharyngeal Dysfunction: Impact of 22q11.2 Deletion Syndrome.

OBJECTIVE: Patients with 22q11.2 deletion syndrome (22q11DelS) often present with velopharyngeal dysfunction (VPD). VPD in patients with 22q11DelS is multifactorial beyond velopharyngeal insufficiency (VPI) alone, and differences in surgical outcomes are poorly understood. Our objective was to determine whether patients with 22q11DelS have an increased risk for persistent VPI after sphincter pharyngoplasty compared to patients without 22q11DelS. METHODS: We completed a retrospective cohort study of patients with 22q11DelS undergoing sphincter pharyngoplasty between 1995 and 2019 using a VPD clinic database. Patients with 22q11DelS were compared to a cohort of 2:1 frequency-matched (age, degree of velopharyngeal closure) patients without 22q11DelS. Variables included patient characteristics, surgical history, perceptual speech evaluation, and degree of closure on nasopharyngoscopic evaluations. Primary outcomes included postoperative VPI severity and hypernasality. Speech and nasopharyngoscopic characteristics were compared using Fisher's exact test. Postoperative VPI severity and hypernasality were compared between groups via relative risks (RR) from mixed effects Poisson regression models, with random effects of age and velopharyngeal closure. RESULTS: 134 patients (51 22q11DelS, 83 matched) were included, with mean age of 7.3 years (standard deviation 3.0) and 50% male. Cohorts had similar preoperative speech characteristics and nasopharyngoscopic findings. Patients with 22q11DelS had similar postoperative VP function as patients without 22q11DelS (RR 0.85, CI 0.46-1.57 for VPI severity, RR 0.83, CI 0.45-1.53 for hypernasality). Even after adjusting by preoperative variables, no differences were seen between both groups. CONCLUSION: Matched for age and pre-operative velopharyngeal closure, patients with and without 22q11DelS and VPI had similar benefits after sphincter pharyngoplasty. LEVEL OF EVIDENCE: Non-randomized controlled cohort study, 3 Laryngoscope, 133:2813-2820, 2023.

American society of pediatric otolaryngology vascular anomalies task force review of tongue venous malformations: Techniques, pearls, and pitfalls.

Management of tongue venous malformations can be challenging in the pediatric population due to their heterogeneity in presentation, extent of involvement and functional compromise. It is important to recognize the value of various treatment options in order to guide management of each patient in an individualized fashion. Here we describe a series of patients with tongue venous malformations that are managed using diverse modalities to illustrate the relative benefits and risks of each technique. The challenges of venous malformation treatment can be mitigated by tailoring the approach to each individual patient and malformation. This case series also emphasizes the need and importance of working in the setting of a multidisciplinary vascular anomalies team.

Primary targeted medical therapy for management of bilateral head and neck lymphatic malformations in infants.

OBJECTIVES: Patients born with bilateral head and neck lymphatic malformations (BHNLMs) often require multiple invasive treatments, including tracheostomy. We hypothesized that primary targeted medical therapy (pTMT) with diagnostic needle aspiration reduces the need for invasive therapy such as surgical resection and/or sclerotherapy. METHODS: Retrospective case review was performed of infants with BHNLMs (Grade 2 or De Serres stage IV and V) treated only at our institution from 2000 to 2021. Patients were divided into two cohorts: those managed with pTMT and those managed with observation, sclerotherapy, or surgical intervention (non-pTMT). Data regarding interventions, clinical outcomes, morbidity, and mortality were analyzed with descriptive statistics. RESULTS: Nine children with BHNLMs met inclusion criteria. Three (33%) were in the pTMT cohort and six (66%) were non-pTMT. Eight (89%) malformations were genotyped, and all demonstrated hotspot PIK3CA variants. All pTMT patients had sirolimus initiated in the first month of life and underwent needle aspiration of malformation cyst fluid for cell-free DNA samples. All pTMT patients tolerated medical therapy. For the non-pTMT cohort, primary treatment included none (deceased, n = 1, 17%), observation with needle aspiration (n = 1, 17%), surgical resection (n = 2, 33%), or combination surgery and sclerotherapy (n = 2, 33%). Intubation duration, intensive care and initial hospital length of stay were not different between cohorts. Four non-pTMT patients (67%) required tracheostomy, and two (33%) died prior to discharge. All pTMT patients survived and none required tracheostomy. Non-pTMT patients required a median of two invasive therapies prior to discharge (IQR 1-4) and a mean total of 13 over the course of their lifetime (IQR 1-16), compared to the pTMT group who did not require any lifetime invasive therapy, even after initial pTMT and discharge home. CONCLUSION: This study compares patients with BHNLMs (Grade 2) treated with pTMT versus those treated with observation or invasive therapy. Patients treated with pTMT required no surgical or invasive procedural treatment of their malformations, no tracheostomy placement, no unplanned readmissions after discharge, and had no mortalities. Needle aspiration was useful as a therapeutic adjunct for cell-free DNA diagnosis of PIK3CA variants, which guided TMT.

Predictors of Success After Furlow Palatoplasty for Repair of Cleft Palate: Does Syndrome Matter?

OBJECTIVE: To determine predictors of success following Veau 1 and 2 cleft palate repair in patients with and without syndromes. STUDY DESIGN: Retrospective review of prospectively collected data. SETTING: Tertiary care children's hospital. METHODS: All children <18 months of age undergoing Furlow palatoplasty for Veau 1 and 2 cleft repair between 2000 and 2014 with postoperative perceptual speech assessment (PSA). RESULTS: In total, 368 consecutive patients were identified; 95 were excluded, resulting in 273 patients. Median age at surgery was 13.0 months (interquartile range [IQR], 11-15 months) with postoperative PSA at a median of 32.3 months (IQR, 26.3-44.5 months). Fifty patients (18.3%) had syndrome diagnosis; 59 patients (21.6%) had nonsyndromic Robin sequence. Velopharyngeal insufficiency (VPI) occurred in 27 patients (10.5%); 13 underwent secondary speech surgery. Cleft-related speech errors occurred in 46 patients (17.6%). Non-cleft-related speech errors occurred in 155 patients (59.6%) and reduced intelligibility in 127 patients (47.9%). Oronasal fistula occurred in 23 patients (8.8%) and was exclusive to Veau 2 clefts. In multivariate analysis, age >13 months at palatoplasty demonstrated a 6-fold higher rate of VPI (hazard ratio [HR], 6.64; P < .01), worse speech outcomes (HR, 6.04; P < .01; HR, 1.60; P < .01; HR, 1.57; P = .02), and greater speech therapy utilization (HR, 2.18; P < .01). CONCLUSION: VPI occurred in 10% of patients undergoing Furlow palatoplasty repair of Veau 1 or 2 clefts. Age <13 months at palatoplasty was associated with improved speech outcomes and lower VPI incidence (2.8% vs 16.2%). Syndromic diagnosis was associated with noncleft speech errors and reduced intelligibility on univariate analysis but not velopharyngeal function after palatoplasty.

Complex Airway Management in Patients with Tracheal Cartilaginous Sleeves.

OBJECTIVES/HYPOTHESIS: A tracheal cartilaginous sleeve (TCS) is a rare anomaly characterized by anterior fusion of tracheal cartilages. TCS is associated with syndromic craniosynostoses including Apert, Crouzon and Pfeiffer syndromes and FGFR2, FGFR3, and TWIST1 variants. This study presents a 30-year review of patients with syndromic craniosynostosis and TCS and describes diagnostic methods, genetic variants, surgical interventions, and long-term outcomes. STUDY DESIGN: Retrospective, single-institution review. METHODS: This review included patients with syndromic craniosynostosis and TCS treated at Seattle Children's Hospital from 1990 to 2020. Tracheostomy, genetic variants, and additional surgery were primary measures. Fisher's exact test compared need for tracheostomy in patients with proposed high-risk (FGFR2 p.W290 or FGFR2 p.C342) versus low-risk genetic variants. RESULTS: Thirty patients with TCS were identified. Average age at diagnosis was 12 months (range 2-weeks to 7.9-years; standard deviation 19.8 months). Syndromes included Pfeiffer (37%), Apert (37%), and Crouzon (26%). Severe obstructive sleep apnea was present in 76% of patients. Tracheostomy was performed in 17 patients (57%); five were successfully decannulated. Additional interventions included adenotonsillectomy (57%), nasal (20%), laryngeal (17%), and craniofacial skeletal surgery (87%). All patients with Pfeiffer syndrome and FGFR2 p.W290C variants and 83% of patients with FGFR2 p.C342 variants required tracheostomy, differing from other variants (P = .02, odds ratio 33, 95% confidence interval 1.56-697.96). One patient (3%) died. CONCLUSION: TCS contributes to multilevel airway obstruction in patients with syndromic craniosynostosis. Genetic testing in patients with FGFR2-related syndromic craniosynostoses may identify those at risk of TCS and facilitate early intervention. A better understanding of this patient population may foster individualized airway management strategies and improve outcomes. LEVEL OF EVIDENCE: 4 Laryngoscope, 132:215-221, 2022.

Avoidance of surgery for head and neck infantile myofibromatosis using imatinib monotherapy.

Describe a novel use for a kinase inhibitor, imatinib, in young children with a known activated somatic mutation in PDGFR-beta. Two patients with infantile myofibromatosis treated with imatinib. Case description of evaluation, diagnosis and treatment decisions for infantile myfibromatosis of the head and neck. Description of medical therapy for infantile myofibromatosis in these patients. For function threatening myofibromas of a known genotype, in infants, targeted medical therapy is a treatment option.

Somatic activating BRAF variants cause isolated lymphatic malformations.

Somatic activating variants in PIK3CA, the gene that encodes the p110α catalytic subunit of phosphatidylinositol 3-kinase (PI3K), have been previously detected in ∼80% of lymphatic malformations (LMs).1 , 2 We report the presence of somatic activating variants in BRAF in individuals with LMs that do not possess pathogenic PIK3CA variants. The BRAF substitution p.Val600Glu (c.1799T>A), one of the most common driver mutations in cancer, was detected in multiple individuals with LMs. Histology revealed abnormal lymphatic channels with immunopositivity for BRAFV600E in endothelial cells that was otherwise indistinguishable from PIK3CA-positive LM. The finding that BRAF variants contribute to low-flow LMs increases the complexity of prior models associating low-flow vascular malformations (LM and venous malformations) with mutations in the PI3K-AKT-MTOR and high-flow vascular malformations (arteriovenous malformations) with mutations in the RAS-mitogen-activated protein kinase (MAPK) pathway.3 In addition, this work highlights the importance of genetic diagnosis prior to initiating medical therapy as more studies examine therapeutics for individuals with vascular malformations.

Accuracy and Reliability of 4D-CT and Flexible Laryngoscopy in Upper Airway Evaluation in Robin Sequence.

OBJECTIVES: To evaluate the performance of 4-dimensional computed tomography (4D-CT) in assessing upper airway obstruction (UAO) in patients with Robin sequence (RS) and compare the accuracy and reliability of 4D-CT and flexible fiber-optic laryngoscopy (FFL). STUDY DESIGN: Prospective survey of retrospective clinical data. SETTING: Single, tertiary care pediatric hospital. METHODS: At initial and 30-day time points, a multidisciplinary group of 11 clinicians who treat RS rated UAO severity in 32 sets of 4D-CT visualizations and FFL videos (dynamic modalities) and static CT images. Raters assessed UAO at the velopharynx and oropharynx (1 = none to 5 = complete) and noted confidence levels of each rating. Intraclass correlation and Krippendorff alpha were used to assess intra- and interrater reliability, respectively. Accuracy was assessed by comparing clinician ratings with quantitative percentage constriction (QPC) ratings, calculated based on 4D-CT airway cross-sectional area. Results were compared using Wilcoxon rank-sum and signed-rank tests. RESULTS: There was similar intrarater agreement (moderate to substantial) with 4D-CT and FFL, and both demonstrated fair interrater agreement. Both modalities underestimated UAO severity, although 4D-CT ratings were significantly more accurate, as determined by QPC similarity, than FFL (-1.06 and -1.46 vs QPC ratings, P = .004). Overall confidence levels were similar for 4D-CT and FFL, but other specialists were significantly less confident in FFL ratings than were otolaryngologists (2.25 and 3.92, P < .0001). CONCLUSION: Although 4D-CT may be more accurate in assessing the degree of UAO in patients with RS, 4D-CT and FFL assessments demonstrate similar reliability. Additionally, 4D-CT may be interpreted with greater confidence by nonotolaryngologists who care for these patients.

Migration of n-BCA glue as a complication of venous malformation treatment in children.

Preoperative n-butyl cyanoacrylate (n-BCA) embolization of venous malformations facilitates surgical resection. Although embolization is generally well-tolerated, central venous n-BCA migration can occur. The purpose of this article is to describe 3 cases of glue migration requiring glue embolectomy. Strategies for prevention and treatment of glue migration during embolization of venous malformations are reviewed.

Speech Outcomes After Sphincter Pharyngoplasty for Velopharyngeal Insufficiency.

OBJECTIVES/HYPOTHESIS: To investigate perceptual speech outcomes following sphincter pharyngoplasty (SP) and to identify patient characteristics associated with velopharyngeal insufficiency (VPI) resolution or improvement. METHODS: Retrospective review of prospectively collected data was performed of consecutive patients that underwent SP for management of VPI between 1994 and 2016 at a single tertiary care pediatric hospital. Demographic data, nasendoscopic findings, and speech characteristics were recorded using a standardized protocol. Pre- and post-operative VPI was graded on a five-point Likert scale. Frequency of post-operative VPI resolution and improvement was assessed and associations with patient characteristics were analyzed. The association between odds of VPI resolution or improvement and five patient characteristics identified a priori was performed controlling for confounding factors. RESULTS: Two-hundred ninety-six subjects were included. All patients had at least minimal VPI pre-operatively; 72% were graded moderate or severe. Sixty-four percent experienced resolution and 83% improved at least one point on the VPI-severity scale. Of the five patient characteristics, only history of cleft palate repair was significantly associated with decreased odds of VPI improvement but not resolution when controlling for other variables. CONCLUSIONS: Sphincter pharyngoplasty resulted in resolution of VPI in 64% and improvement in 83% of subjects. Children with a history of cleft palate had significantly decreased odds of VPI improvement compared to those without a history of cleft palate. Neither syndrome diagnosis nor 22q11 deletion had a significant association with speech outcomes after sphincter pharyngoplasty. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:E2046-E2052, 2021.

Prenatal Imaging Findings Predict Obstructive Fetal Airways Requiring EXIT.

OBJECTIVE: Detection of fetal airway compromise through imaging raises the possible need for ex utero intrapartum treatment (EXIT) procedures. Despite EXIT procedures involving massive resource utilization and posing increased risk to the mother, decisions for EXIT are usually based on anecdotal experience. Our objectives were to analyze prenatal consultations with potential fetal airway obstruction for imaging and obstetric findings used to determine management strategy. METHODS: Retrospective chart review was performed for prenatal abnormal fetal airway consults between 2004-2019 at a quaternary pediatric facility. Data collected included demographics, imaging characteristics, delivery information, and airway management. Our primary outcome was EXIT performance and the secondary outcome was postnatal airway management. Fisher's exact test was used to compare management decisions, outcomes, and imaging findings. RESULTS: Thirty-seven patients met inclusion criteria. The most common diagnoses observed were lymphatic malformation, teratoma, and micrognathia. Of the imaging findings collected, only midline neck mass location was associated with EXIT procedure performance. Factors associated with invasive airway support at birth were mass-induced in-utero neck extension and neck vessel compression, polyhydramnios, and micrognathia. CONCLUSIONS: Multidisciplinary input and interpretation of prenatal imaging can guide management of fetal airway-related pathology. EXIT is an overall safe procedure and can decrease risk due to airway obstruction at birth. We identified in-utero neck extension, neck vessel compression, micrognathia, and polyhydramnios as better indicators of a need for invasive airways measures at birth and suggest use of these criteria in combination with clinical judgement when recommending EXIT. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:E1357-E1362, 2021.

Genotype-Phenotype Correlation of Tracheal Cartilaginous Sleeves and Fgfr2 Mutations in Mice.

OBJECTIVES: To characterize tracheal cartilage morphology in mouse models of fibroblast growth factor receptor (Fgfr2)-related craniosynostosis syndromes. To establish relationships between specific Fgfr2 mutations and tracheal cartilaginous sleeve (TCS) phenotypes in these mouse models. METHODS: Postnatal day 0 knock-in mouse lines with disease-specific genetic variations in the Fgfr2 gene (Fgfr2C342Y/C342Y , Fgfr2C342Y/+ , Fgfr2+/Y394C , Fgfr2+/S252W , and Fgfr2+/P253R ) as well as line-specific controls were utilized. Tracheal cartilage morphology as measured by gross analyses, microcomputed tomography (µCT), and histopathology were compared using Chi-squared and single-factor analysis of variance statistical tests. RESULTS: A greater proportion of rings per trachea were abnormal in Fgfr2C342Y/+ tracheas (63%) than Fgfr2+/S252W (17%), Fgfr2+/P253R (17%), Fgfr2+/Y394C (12%), and controls (10%) (P < .001 for each vs. Fgfr2C342Y/+ ). TCS segments were found only in Fgfr2C342Y/C342Y (100%) and Fgfr2C342Y/+ (72%) tracheas. Cricoid and first-tracheal ring fusion was noted in all Fgfr2C342Y/C342Y and 94% of Fgfr2C342Y/+ samples. The Fgfr2C342Y/C342Y and Fgfr2C342Y/+ groups were found to have greater areas and volumes of cartilage than other lines on gross analysis and µCT. Histologic analyses confirmed TCS among the Fgfr2C342Y/C342Y and Fgfr2C342Y/+ groups, without appreciable differences in cartilage morphology, cell size, or density; no histologic differences were observed among other Fgfr2 lines compared to controls. CONCLUSION: This study found TCS phenotypes only in the Fgfr2C342Y mouse lines. These lines also had increased tracheal cartilage compared to other mutant lines and controls. These data support further study of the Fgfr2 mouse lines and the investigation of other Fgfr2 variants to better understand their role in tracheal development and TCS formation. LEVEL OF EVIDENCE: NA Laryngoscope, 131:E1349-E1356, 2021.