Characteristics of velopharyngeal dysfunction in 22q11.2 deletion syndrome: a retrospective case-control study

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.

Chromosome 22q11.2 Deletion Syndrome: A Comprehensive Review of Molecular Genetics in the Context of Multidisciplinary Clinical Approach

The 22q11.2 deletion syndrome is a multisystemic disorder characterized by a marked variability of phenotypic features, making the diagnosis challenging for clinicians. The wide spectrum of clinical manifestations includes congenital heart defects-most frequently conotruncal cardiac anomalies-thymic hypoplasia and predominating cellular immune deficiency, laryngeal developmental defects, midline anomalies with cleft palate and velar insufficiency, structural airway defects, facial dysmorphism, parathyroid and thyroid gland hormonal dysfunctions, speech delay, developmental delay, and neurocognitive and psychiatric disorders. Significant progress has been made in understanding the complex molecular genetic etiology of 22q11.2 deletion syndrome underpinning the heterogeneity of clinical manifestations. The deletion is caused by chromosomal rearrangements in meiosis and is mediated by non-allelic homologous recombination events between low copy repeats or segmental duplications in the 22q11.2 region. A range of genetic modifiers and environmental factors, as well as the impact of hemizygosity on the remaining allele, contribute to the intricate genotype-phenotype relationships. This comprehensive review has been aimed at highlighting the molecular genetic background of 22q11.2 deletion syndrome in correlation with a clinical multidisciplinary approach.