Perioperative risk factors in patients with 22q11.2 deletion syndrome requiring surgery for velopharyngeal dysfunction

Prenatal assessment of brain malformations on neuroimaging: an expert panel review

Brain malformations represent a heterogeneous group of abnormalities of neural morphogenesis, often associated with aberrations of neuronal connectivity and brain volume. Prenatal detection of brain malformations requires a clear understanding of embryology and developmental morphology through the various stages of gestation. This expert panel review is written with the central aim of providing an easy-to-understand road map to improve prenatal detection and characterization of structural malformations based on the current understanding of normal and aberrant brain development. For every developmental stage, the utility of each available neuroimaging modality, including prenatal multiplanar neuro sonography, anatomical MRI and advanced MRI techniques, as well as further insights from post-mortem imaging, has been highlighted.

Preoperative Imaging in Patients with 22q11 Deletion Syndrome Undergoing Velopharyngeal Surgery

OBJECTIVE

To evaluate the utility of preoperative imaging before velopharyngeal dysfunction (VPD) surgery in children with 22q11 Deletion Syndrome (22qDS) in evaluating internal carotid artery (ICA) medialization.

DATA SOURCES

PubMed, Scopus, and CINAHL.

REVIEW METHODS

Following PRISMA guidelines, a systematic review was performed. Studies of children with 22qDS who underwent preoperative imaging (MRA or CTA) to identify ICA anomalies were included. High-risk medialized ICAs were defined as either submucosal, retropharyngeal, Pfeiffer Grade III-IV, or <3 mm from the pharyngeal mucosa. Meta-analyses of proportions were performed.

RESULTS

Eleven studies met inclusion criteria, comprising 398 patients with 22qDS (weighted mean age 7.6 years). In 372 patients with imaging, the rate of ICA medialization on imaging was 47.1% (95%CI 29.2-65.5), of which 46.3% (95%CI 27.4-65.8) were determined high risk. Operative plans were modified in 19.4% (95%CI 5.7-38.8) of 254 surgeries due to medialized ICA. In studies attempting to use nasopharyngoscopy pulsations to identify medialization for 214 patients, the true-positive rate was 53.9% (95%CI 27.5-79.2) and the false-positive rate was 16.2% (95%CI 7.9-26.8). Nine of eleven studies (81.8%) recommended universal preoperative imaging of the ICAs in children with 22qDS undergoing VPD surgery. No cases of perioperative bleeding secondary to ICA injury were identified.

CONCLUSION

Although most studies endorse routine preoperative imaging to assess for ICA medialization in children with 22qDS undergoing VPD surgery, only a minority of these cases led to surgical modification. Additional studies are needed to compare outcomes in children with and without preoperative imaging given the low rates of ICA injury in the literature.

LEVEL OF EVIDENCE

N/A Laryngoscope, 134:2551-2561, 2024.

Updated clinical practice recommendations for managing adults with 22q11.2 deletion syndrome

This review aimed to update the clinical practice guidelines for managing adults with 22q11.2 deletion syndrome (22q11.2DS). The 22q11.2 Society recruited expert clinicians worldwide to revise the original clinical practice guidelines for adults in a stepwise process according to best practices: (1) a systematic literature search (1992-2021), (2) study selection and synthesis by clinical experts from 8 countries, covering 24 subspecialties, and (3) formulation of consensus recommendations based on the literature and further shaped by patient advocate survey results. Of 2441 22q11.2DS-relevant publications initially identified, 2344 received full-text review, with 2318 meeting inclusion criteria (clinical care relevance to 22q11.2DS) including 894 with potential relevance to adults. The evidence base remains limited. Thus multidisciplinary recommendations represent statements of current best practice for this evolving field, informed by the available literature. These recommendations provide guidance for the recognition, evaluation, surveillance, and management of the many emerging and chronic 22q11.2DS-associated multisystem morbidities relevant to adults. The recommendations also address key genetic counseling and psychosocial considerations for the increasing numbers of adults with this complex condition.

22q11.2 Deletion Syndrome: Impact of Genetics in the Treatment of Conotruncal Heart Defects

Congenital heart diseases represent one of the hallmarks of 22q11.2 deletion syndrome. In particular, conotruncal heart defects are the most frequent cardiac malformations and are often associated with other specific additional cardiovascular anomalies. These findings, together with extracardiac manifestations, may affect perioperative management and influence clinical and surgical outcome. Over the past decades, advances in genetic and clinical diagnosis and surgical treatment have led to increased survival of these patients and to progressive improvements in postoperative outcome. Several studies have investigated long-term follow-up and results of cardiac surgery in this syndrome. The aim of our review is to examine the current literature data regarding cardiac outcome and surgical prognosis of patients with 22q11.2 deletion syndrome. We thoroughly evaluate the most frequent conotruncal heart defects associated with this syndrome, such as tetralogy of Fallot, pulmonary atresia with major aortopulmonary collateral arteries, aortic arch interruption, and truncus arteriosus, highlighting the impact of genetic aspects, comorbidities, and anatomical features on cardiac surgical treatment.

Neurosurgical Evaluation and Management of Patients with Chromosomal Abnormalities

Patients with chromosomal abnormalities are at risk for numerous neurosurgical pathologies, given the broad impact and multisystem involvement of these disorders. Down syndrome (trisomy 21), Edwards syndrome (trisomy 18), Patau syndrome (trisomy 13), Klinefelter syndrome (47,XXY), and velocardiofacial or DiGeorge syndrome (22q11.2 deletion) are particularly associated with neurosurgical concerns. Given the heterogeneity of concerns and presentations, these patients benefit from multidisciplinary care provided by teams familiar with their specific syndrome.

The spectrum of brain malformations and disruptions in twins

Twins have an increased risk for congenital malformations and disruptions, including defects in brain morphogenesis. We analyzed data on brain imaging, zygosity, sex, and fetal demise in 56 proband twins and 7 less affected co-twins with abnormal brain imaging and compared them to population-based data and to a literature series. We separated our series into malformations of cortical development (MCD, N = 39), cerebellar malformations without MCD (N = 13), and brain disruptions (N = 11). The MCD group included 37/39 (95%) with polymicrogyria (PMG), 8/39 (21%) with pia-ependymal clefts (schizencephaly), and 15/39 (38%) with periventricular nodular heterotopia (PNH) including 2 with PNH but not PMG. Cerebellar malformations were found in 19 individuals including 13 with a cerebellar malformation only and another 6 with cerebellar malformation and MCD. The pattern varied from diffuse cerebellar hypoplasia to classic Dandy-Walker malformation. Brain disruptions were seen in 11 individuals with hydranencephaly, porencephaly, or white matter loss without cysts. Our series included an expected statistically significant excess of monozygotic (MZ) twin pairs (22/41 MZ, 54%) compared to population data (482/1448 MZ, 33.3%; p = .0110), and an unexpected statistically significant excess of dizygotic (DZ) twins (19/41, 46%) compared to the literature cohort (1/46 DZ, 2%; p < .0001. Recurrent association with twin-twin transfusion syndrome, intrauterine growth retardation, and other prenatal factors support disruption of vascular perfusion as the most likely unifying cause.

Magnetic resonance angiography (MRA) in preoperative planning for patients with 22q11.2 deletion syndrome undergoing craniofacial and otorhinolaryngologic procedures

INTRODUCTION

Patients with 22q11.2 deletion syndrome (22q11.2DS) have a variety of anatomic anomalies. For surgeons operating in proximity to the retropharynx, the most pertinent is medial displacement of the internal carotid arteries. The purpose of this study is to describe the preoperative use of magnetic resonance angiography (MRA) in surgical planning and update the incidence rate of medial carotid displacement in patients with 22q11.2DS.

METHODS

This is a retrospective cohort study of patients with a confirmed diagnosis of 22q11.2 deletion and preoperative MRA <18 years old who underwent tonsillectomy, adenoidectomy, Furlow palatoplasty (FPP), posterior pharyngeal flap (PPF), sphincter pharyngoplasty (SPP), or submucosal cleft palate (SMCP) repair between January 1st, 2008 and December 31st, 2019.

RESULTS

Ninety patients who met the inclusion criteria underwent 133 procedures. The majority identified as Caucasian (84.4%); 52.2% were female. Cervical MRA was more likely to be ordered before a PPF (80.9%) and tonsillectomy (72.7%) over a FPP (47.6%) or adenoidectomy (11.1%). Carotid medialization was visualized in 23 patients (25.6%) and was mild in 11 cases, moderate in 7 cases, and significant in 5 cases. There was no association between sex, race/ethnicity, or genetic diagnosis with carotid medialization. Flap shortening was necessary in 20% of PPF cases to avoid injuring the medialized vessel.

CONCLUSION

Patients with 22q11.2DS may have higher rates of medialization of the carotid arteries than previously thought. Given the risk for complications in these patients during pharyngeal operations, there may be a critical place for MRA in surgical planning for patients with 22q11.2DS.

The Clinical Utility of Flexion-extension Cervical Spine MRI in 22q11.2 Deletion Syndrome

BACKGROUND

Our goal is to correlate the findings on flexion and extension radiographs with dynamic magnetic resonance imaging (MRI), and the clinical history, in a nonrandomly selected cohort of patients with 22q11.2 deletion syndrome (22q).

METHODS

All patients with the 22q who had a dynamic MRI from January 2004 to March 2015 were included. We analyzed multiple radiographic measurements on both the dynamic plain films and the MRIs, and correlated these findings with a review of each patient's medical record.

RESULTS

Multiple congenital anomalies were identified as noted in previous studies, and 61% of the patients had a failure of fusion of the anterior (n=2, 9%), posterior (n=2, 9%), or anterior and posterior arches (n=10, 43%). Quantitative measurements were impossible to report with certainty because of the upper cervical anomalies, and no cases of instability were identified using a qualitative assessment. We identified spinal cord encroachment (30%) and impingement (18%); however, none of the patients had any signal change in their spinal cord. None of these findings could be definitively correlated with any clinical symptoms. A single patient was diagnosed with a Chiari I malformation, while another had cerebellar ectopia.

CONCLUSIONS

Although the upper cervical anomalies are extremely common in 22q, we did not identify cases of instability on dynamic plain radiographs and MRI. Although our findings do not support routine screening with flexion and extension MRI, this study may be required in patients with neurological symptoms and/or findings or abnormalities on dynamic plain radiographs.

LEVEL OF EVIDENCE

Level III.

Palatal evaluation and treatment in 22q11.2 deletion syndrome

Palatal involvement occurs commonly in patients with 22q11.2 Deletion Syndrome (22qDS), and includes palatal clefting and velopharyngeal dysfunction in the absence of overt or submucous clefts. The reported incidence and distribution of palatal abnormalities vary in the literature. The aim of this article is to revisit the incidence and presenting features of palatal abnormalities in a large cohort of patients with 22qDS, summarize the surgical treatments performed in this cohort, and provide an overview of surgical treatment protocols and management guidelines for palatal abnormalities in this syndrome. Charts of 1,121 patients seen through the 22q and You Center at the Children's Hospital of Philadelphia were reviewed for palatal status, demographic factors, deletion size, and corrective surgical procedures. Statistical analysis was performed using Pearson's chi-squared test to identify differences between gender, deletion size, and palatal abnormality. Of the patients with complete evaluations, 67% were found to have a palatal abnormality. The most common finding was velopharyngeal dysfunction in 55.2% of patients, and in 33.3% of patients, this occurred in the absence of palatal clefting. There was no significant difference in the incidence of palatal abnormalities by gender; however, a difference was noted among race (p < 0.01) and deletion sizes (p < 0.01). For example, Caucasian and Asian patients presented with a much higher prevalence of palatal abnormalities, and conversely those with nested deletions presented with a much lower rate of palatal defects. Overall, 26.9% of patients underwent palatal surgery, and the most common indication was velopharyngeal dysfunction. Palatal abnormalities are a hallmark feature of 22q11.2 Deletion Syndrome; understanding the incidence, presenting features, and treatment protocols are essential for practitioners counseling and treating families affected with this disorder.

Management of velopharyngeal dysfunction in patients with 22q11.2 deletion syndrome: A survey of practice patterns

OBJECTIVE

To determine demographics and practice patterns of surgeons treating velopharyngeal dysfunction (VPD) in patients with 22q11.2 deletion syndrome (22q11.2DS).

METHODS

An anonymous electronic survey study was administered to the surgical membership of the American Cleft Palate-Craniofacial Association and the Society for Ear Nose and Throat Advances in Children. The survey queried surgeon demographics and differences in management practices for submucous cleft palate (SMCP), pharyngoplasty algorithms, and self-reported complications for nonsyndromic versus 22q11.2DS patients.

RESULTS

126 surveys were returned from 9 international regions with the majority from the United States (73%), followed by Western Europe (9.5%) and Canada (7.9%). Plastic surgery was the most common specialty (61.9%), followed by otolaryngology (27.8%). 88.1% reported fellowship training, and 33% completed multiple fellowships. Prior to proceeding with pharyngoplasty in 22q11.2DS patients, surgeons required the following assessments: speech evaluation (79.4%), velopharyngeal imaging (51.6%), cardiac evaluation (50.0%), carotid artery MRI (29.4%), and cervical spine x-rays (11.1%). Nasoendoscopy was the most common modality used for imaging the velopharynx. Overall, providers managed patients with 22q11.2DS similarly to nonsyndromic patients, with several significant exceptions including that they were more likely to perform SMCP repair alone as a first approach in nonsyndromic patients (p = 0.031) and posterior pharyngeal flap without SMCP repair in those with 22q11.2DS (p = 0.017).

CONCLUSIONS

Practice patterns for the management of VPD in patients with 22q11.2DS vary across providers. Further collaborative studies are needed to develop optimal treatment paradigms for VPD in patients with 22q11.2 DS.

Congenital heart diseases and cardiovascular abnormalities in 22q11.2 deletion syndrome: From well-established knowledge to new frontiers

Congenital heart diseases (CHDs) and cardiovascular abnormalities are one of the pillars of clinical diagnosis of 22q11.2 deletion syndrome (22q11.2DS) and still represent the main cause of mortality in the affected children. In the past 30 years, much progress has been made in describing the anatomical patterns of CHD, in improving their diagnosis, medical treatment, and surgical procedures for these conditions, as well as in understanding the underlying genetic and developmental mechanisms. However, further studies are still needed to better determine the true prevalence of CHDs in 22q11.2DS, including data from prenatal studies and on the adult population, to further clarify the genetic mechanisms behind the high variability of phenotypic expression of 22q11.2DS, and to fully understand the mechanism responsible for the increased postoperative morbidity and for the premature death of these patients. Moreover, the increased life expectancy of persons with 22q11.2DS allowed the expansion of the adult population that poses new challenges for clinicians such as acquired cardiovascular problems and complexity related to multisystemic comorbidity. In this review, we provide a comprehensive review of the existing literature about 22q11.2DS in order to summarize the knowledge gained in the past years of clinical experience and research, as well as to identify the remaining gaps in comprehension of this syndrome and the possible future research directions.

22q and two: 22q11.2 deletion syndrome and coexisting conditions

22q11.2 deletion syndrome (DS) is the most frequent copy number variant (CNV) affecting ~1/1,000 fetuses and ~1/2,000-4,000 children, resulting in recognizable but variable findings across multiple organ systems. Patients with atypical features should prompt consideration of coexisting diagnoses due to additional genome-wide mutations, CNVs, or mutations/CNVs on the other allele, unmasking autosomal recessive conditions. Importantly, a dual diagnosis compounds symptoms and impacts management. We previously reported seven patients with 22q11.2DS and: SCID, Trisomy 8 mosaicism, Bernard-Soulier, and CEDNIK syndromes. Here we present six additional unreported patients with 22q11.2DS and concurrent diagnoses. Records on 1,422 patients with 22q11.2DS, identified via FISH, microarray, or MLPA, followed in our 22q and You Center at the Children's Hospital of Philadelphia (CHOP) were reviewed to identify a dual diagnosis. In addition to our seven previously reported cases, we identified an additional six with 22q11.2DS and another coexisting condition identified via: molecular/cytogenetic studies, newborn screening, coagulation factor studies, or enzyme testing; these include CHARGE syndrome (CHD7 mutation), cystic fibrosis, a maternally inherited 17q12 deletion, G6PD deficiency, von Willebrand disease, and 1q21.1 deletion, resulting in an incidence of dual diagnoses at our center of 0.9%. The range of dual diagnoses identified in our cohort is notable, medically actionable, and may alter long-term outcome and recurrence risk counseling. Thus, our findings may support testing patients with 22q11.2DS using a combination of microarray, mutational analysis of the other allele/WES, to ensure appropriate personalized care, as formulating medical management decisions hinges on establishing the correct diagnoses in their entirety.

22q11.2 deletion syndrome

22q11.2 deletion syndrome (22q11.2DS) is the most common chromosomal microdeletion disorder, estimated to result mainly from de novo non-homologous meiotic recombination events occurring in approximately 1 in every 1,000 fetuses. The first description in the English language of the constellation of findings now known to be due to this chromosomal difference was made in the 1960s in children with DiGeorge syndrome, who presented with the clinical triad of immunodeficiency, hypoparathyroidism and congenital heart disease. The syndrome is now known to have a heterogeneous presentation that includes multiple additional congenital anomalies and later-onset conditions, such as palatal, gastrointestinal and renal abnormalities, autoimmune disease, variable cognitive delays, behavioural phenotypes and psychiatric illness - all far extending the original description of DiGeorge syndrome. Management requires a multidisciplinary approach involving paediatrics, general medicine, surgery, psychiatry, psychology, interventional therapies (physical, occupational, speech, language and behavioural) and genetic counselling. Although common, lack of recognition of the condition and/or lack of familiarity with genetic testing methods, together with the wide variability of clinical presentation, delays diagnosis. Early diagnosis, preferably prenatally or neonatally, could improve outcomes, thus stressing the importance of universal screening. Equally important, 22q11.2DS has become a model for understanding rare and frequent congenital anomalies, medical conditions, psychiatric and developmental disorders, and may provide a platform to better understand these disorders while affording opportunities for translational strategies across the lifespan for both patients with 22q11.2DS and those with these associated features in the general population.

22q11 deletion syndrome: current perspective

Chromosome 22q11 is characterized by the presence of chromosome-specific low-copy repeats or segmental duplications. This region of the chromosome is very unstable and susceptible to mutations. The misalignment of low-copy repeats during nonallelic homologous recombination leads to the deletion of the 22q11.2 region, which results in 22q11 deletion syndrome (22q11DS). The 22q11.2 deletion is associated with a wide variety of phenotypes. The term 22q11DS is an umbrella term that is used to encompass all 22q11.2 deletion-associated phenotypes. The haploinsufficiency of genes located at 22q11.2 affects the early morphogenesis of the pharyngeal arches, heart, skeleton, and brain. TBX1 is the most important gene for 22q11DS. This syndrome can ultimately affect many organs or systems; therefore, it has a very wide phenotypic spectrum. An increasing amount of information is available related to the pathogenesis, clinical phenotypes, and management of this syndrome in recent years. This review summarizes the current clinical and genetic status related to 22q11DS.