In Search of the Optimal Surgical Treatment for Velopharyngeal Dysfunction in 22q11.2 Deletion Syndrome: A Systematic Review

<div><h3>Background</h3><p>Patients with the 22q11.2 deletion syndrome (22qDS) and velopharyngeal dysfunction (VPD) tend to have residual VPD following surgery. This systematic review seeks to determine whether a particular surgical procedure results in superior speech outcome or less morbidity.</p> <h3>Methodology/ Principal Findings</h3><p>A combined computerized and hand-search yielded 70 studies, of which 27 were deemed relevant for this review, reporting on a total of 525 patients with 22qDS and VPD undergoing surgery for VPD. All studies were levels 2c or 4 evidence. The methodological quality of these studies was assessed using criteria based on the Cochrane Collaboration's tool for assessing risk of bias. Heterogeneous groups of patients were reported on in the studies. The surgical procedure was often tailored to findings on preoperative imaging. Overall, 50% of patients attained normal resonance, 48% attained normal nasal emissions scores, and 83% had understandable speech postoperatively. However, 5% became hyponasal, 1% had obstructive sleep apnea (OSA), and 17% required further surgery. There were no significant differences in speech outcome between patients who underwent a fat injection, Furlow or intravelar veloplasty, pharyngeal flap pharyngoplasty, Honig pharyngoplasty, or sphincter pharyngoplasty or Hynes procedures. There was a trend that a lower percentage of patients attained normal resonance after a fat injection or palatoplasty than after the more obstructive pharyngoplasties (11–18% versus 44–62%, p = 0.08). Only patients who underwent pharyngeal flaps or sphincter pharyngoplasties incurred OSA, yet this was not statistically significantly more often than after other procedures (p = 0.25). More patients who underwent a palatoplasty needed further surgery than those who underwent a pharyngoplasty (50% versus 7–13%, p = 0.03).</p> <h3>Conclusions/ Significance</h3><p>In the heterogeneous group of patients with 22qDS and VPD, a grade C recommendation can be made to minimize the morbidity of further surgery by choosing to perform a pharyngoplasty directly instead of only a palatoplasty.</p> </div

A candidate gene approach to identify modifiers of the palatal phenotype in 22q11.2 deletion syndrome patients

Objective Palatal anomalies are one of the identifying features of 22q11.2 deletion syndrome (22q11.2DS) affecting about one third of patients. To identify genetic variants that increase the risk of cleft or palatal anomalies in 22q11.2DS patients, we performed a candidate gene association study in 101 patients with 22q11.2DS genotyped with the Affymetrix genome-wide human SNP array 6.0. Methods Patients from Children's Hospital of Philadelphia, USA and Wilhelmina Children's Hospital Utrecht, The Netherlands were stratified based on palatal phenotype (overt cleft, submucosal cleft, bifid uvula). SNPs in 21 candidate genes for cleft palate were analyzed for genotype–phenotype association. In addition, TBX1 sequencing was carried out. Quality control and association analyses were conducted using the software package PLINK. Results Genotype and phenotype data of 101 unrelated patients (63 non-cleft subjects (62.4%), 38 cleft subjects (37.6%)) were analyzed. A Total of 39 SNPs on 10 genes demonstrated a p-value ≤0.05 prior to correction. The most significant SNPs were found on FGF10. However none of the SNPs remained significant after correcting for multiple testing. Conclusions Although these results are promising, analysis of additional samples will be required to confirm that variants in these regions influence risk for cleft palate or palatal anomalies in 22q11.2DS patients