Examining a New Method to Studying Velopharyngeal Structures in a Child With 22q11.2 Deletion Syndrome

Do Palatoplasty Procedures Resolve Hypernasality as Effectively as Pharyngoplasty Procedures in Patients with 22q11.2 Deletion Syndrome?

OBJECTIVE

Compare the effectiveness of palatoplasty and pharyngoplasty procedures at resolving hypernasality in patients with 22q11.2 deletion syndrome (22q).

DESIGN

Retrospective cohort study.

SETTING

Metropolitan children's hospital.

PATIENTS

Fourteen patients with 22q presenting for management of velopharyngeal insufficiency.

INTERVENTIONS

Palatoplasty or pharyngoplasty procedure.

MAIN OUTCOME MEASURE

Resolution of hypernasality 12 months postoperatively.

RESULTS

Both procedure groups had a mean preoperative velopharyngeal gap of 6.2 mm during phonation. No patient who underwent palatoplasty achieved resolution of hypernasality; 1/7 patients had worse hypernasality, 4/7 had no change, and 2/7 had improved hypernasality. In contrast, hypernasality was resolved in 6/7 patients in the pharyngoplasty group, which was significantly (P = .03) higher than the palatoplasty group.

CONCLUSIONS

In patients with 22q, palatoplasty procedures may be less effective than pharyngoplasty procedures at resolving hypernasality. This may be due to underlying anatomic or physiologic differences, such as increased pharyngeal depth and hypodynamic muscles.

Magnetic Resonance Imaging of the Velopharynx: Clinical Findings in Patients with Velopharyngeal Insufficiency

BACKGROUND

Magnetic resonance imaging (MRI) is the only imaging modality capable of directly visualizing the levator veli palatini (LVP) muscles: the primary muscles responsible for velopharyngeal closure during speech. MRI has been used to describe normal anatomy and physiology of the velopharynx in research studies, but there is limited experience with use of MRI in the clinical evaluation of patients with velopharyngeal insufficiency (VPI).

METHODS

MRI was used to evaluate the velopharyngeal mechanism in patients presenting for VPI management. The MRI followed a fully awake, nonsedated protocol with phonation sequences. Quantitative and qualitative measures of the velopharynx were obtained and compared with age- and sex-matched individuals with normal speech resonance.

RESULTS

MRI was completed successfully in 113 of 118 patients (96%). Compared with controls, patients with VPI after cleft palate repair had a shorter velum (P < 0.001), higher incidence of LVP discontinuity (P < 0.001), and shorter effective velar length (P < 0.001). Among patients with persistent VPI after pharyngeal flap placement, findings included a pharyngeal flap base located inferior to the palatal plane [11 of 15 (73%)], shorter velum (P < 0.001), and higher incidence of LVP discontinuity (P = 0.014). Patients presenting with noncleft VPI had a shorter (P = 0.004) and thinner velum (P < 0.001) and higher incidence of LVP discontinuity (P = 0.014).

CONCLUSIONS

MRI provides direct evidence of LVP muscle anomalies and quantitative evaluation of both velar length and velopharyngeal gap. This information is unavailable with traditional VPI imaging tools, suggesting that MRI may be a useful tool for selecting surgical procedures to address patient-specific anatomic differences.

Magnetic Resonance Imaging for Assessing Velopharyngeal Function: Current Applications, Barriers, and Potential for Future Clinical Translation in the United States

OBJECTIVE

The use of magnetic resonance imaging (MRI) in the assessment process for children with cleft/craniofacial conditions remains uncommon, particularly for velopharyngeal assessments. The purpose of this study was to analyze the perceived clinical utility of MRI for cleft/craniofacial providers and identify barriers that exist for clinical translation of this imaging modality to this population of patients.

METHODS

A 38-item survey was disseminated to craniofacial team providers. Workplace context and demographics, MRI as a research and clinical tool, access and barriers for use of MRI, and needs for successfully establishing MRI protocols at clinical sites were investigated. Descriptive statistics were used to identify differences in the clinical use of MRI across disciplines. Chi-square analyses were conducted to determine how different specialties perceived potential barriers.

RESULTS

Respondents reported that MRI is likely to be beneficial for clinical assessments (93.5%) and that this imaging modality is available for use (83.8%). However, only 11.8% of providers indicated the use of MRI in their clinical assessments. This discrepancy highlights a potential disconnect between perceived use and implementation of this imaging methodology on cleft and craniofacial teams. A number of barriers were identified by providers. Challenges and opportunities for clinical translation of MRI protocols were highlighted.

CONCLUSION

Results may guide the development for improved clinical feasibility and implementation of MRI for clinical planning in this population of patients. Reported barriers highlight additional areas for translational research and the potential for the development of clinical tools related to MRI assessment and protocol implementation.

VPI Management in SATB2 Syndrome: Use of MRI to Evaluate Anatomy and Physiology in Non-Cleft VPI

This clinical case study describes the velopharyngeal anatomy and physiology in a patient who presented with SATB2-associated syndrome (SAS) and velopharyngeal insufficiency (VPI) in the absence of an overt cleft palate. The clinical presentation, treatment, outcome, and the contribution of anatomical findings from MRI to surgical treatment planning for this rare genetic disorder, SAS, are described. This case study contributes to our current understanding of the anatomy and physiology of the velopharyngeal mechanism in an individual born with SAS and non-cleft VPI. It also details the changes following bilateral buccal myomucosal flaps in this patient.

Assessment of the Velopharyngeal Mechanism at Rest and During Speech in Children With 22q11.2DS: A Cross-Sectional Study

OBJECTIVE

Velopharyngeal dysfunction (VPD) associated with 22q11.2 deletion syndrome (22q11.2DS) has a complex etiology. This study had 3 aims: (1) assess differences in velopharyngeal and levator muscle configuration during rest versus sustained speech production (2) compare differences in velopharyngeal changes between children with and without 22q11.2DS (3) examine the relationship between adenoid thickness, pharyngeal depth, and velopharyngeal changes.

DESIGN

Cross-sectional.

METHODS

A total of 22 participants, 11 with 22q11.2DS and 11 controls with normal speech and velopharyngeal anatomy (ages 4-12 years), underwent nonsedated MRI at rest and during sustained /i/. Differences in velar and levator muscle contraction across the 2 different conditions were analyzed, using matched paired t-tests. Mean differences across participant groups were examined. Correlation analyses were also conducted.

RESULTS

When comparing differences between rest and sustained phoneme production (aim 1), significant (P < .05) differences were noted for all velar and levator muscle variables. For differences in velopharyngeal changes between children with and without 22q11.2DS (aim 2), VP ratio and effective VP ratio were noted to be significantly different. Pharyngeal depth and adenoid thickness were correlated with velar and levator muscle change measures and ratios (aim 3).

CONCLUSION

Results from this study provide quantitative in vivo measurements of the contracted levator muscle and velum in young children with 22q11.2DS. Results demonstrated that VP ratio and EVP ratio are significantly different between children with and without 22q11.2DS and that pharyngeal depth is a strong clinical determinant of VPD in children with 22q11.2DS.

Pharyngeal Flap Versus Sphincter Pharyngoplasty for the Treatment of Velopharyngeal Insufficiency in 22q11.2 Deletion Syndrome: Preliminary Findings From a Systematic Review

The purpose of this study was to examine and compare surgical and speech outcomes of the posterior pharyngeal flap and sphincter pharyngoplasty following surgical management of velopharyngeal insufficiency in patients with 22q11.2 deletion syndrome (22q11.2DS). This systematic review followed the Preferred Reporting Items for Systematic Review and Meta-Analyses checklist and guidelines. Selected studies were chosen using a 3-step screening process. The 2 primary outcomes of interest were speech improvement and surgical complications. Preliminary findings based on included studies suggest a slightly higher rate of postoperative complications with the posterior pharyngeal flap in patients with 22q11.2DS but a lower percentage of patients needing additional surgery compared with the sphincter pharyngoplasty group. The most reported postoperative complication was obstructive sleep apnea. Results from this study provide some insight into speech and surgical outcomes following pharyngeal flap and sphincter pharyngoplasty in patients with 22q11.2DS. However, these results should be interpreted with caution due to inconsistencies in speech methodology and lack of detail regarding surgical technique in the current literature. There is a significant need for standardization of speech assessments and outcomes to help optimize surgical management of velopharyngeal insufficiency in individuals with 22q11.2DS.

Is there a correlation between skull base flexure and palatal anomalies in patients with 22q11 deletion syndrome and velopharyngeal dysfunction?

The study aimed at assessing the relationship between skull base morphology, represented by skull base and nasopharyngeal angles, and palatal anatomy among patients with 22q11DS and velopharyngeal dysfunction. Retrospective analysis of patients with 22q11DS and velopharyngeal dysfunction. Age, sex, severity of velopharyngeal dysfunction, type of cleft (overt cleft palate, submucous cleft palate, occult submucous cleft palate, or no-CP, and cephalometric skull base angles were reviewed. Correlations between type of palatal anomaly and the angles were assessed. Among 132 patients, 71 were male (53.8%) and 61 were female (46.2%), ages 3.3-40.0 years (mean 8.3 ± 6.10). No difference in the mean cranial-base angle (P = 0.353) or in the distribution of the three types of cranial base angle sizes was found among the palatal anomaly groups (P = 0.137). More men had normal cranial base angles and more women had acute angulation (P = 0.008). A positive correlation was found between the skull base and nasopharyngeal angles (P = 0.001, r = -0.590). No direct correlation was found between cranial base morphology and palatal anomalies in patients with 22q11DS, and velopharyngeal dysfunction. This is probably because skull base and palate morphology contribute independently to velopharyngeal dysfunction.

Interaction of the craniofacial complex and velopharyngeal musculature on speech resonance in children with 22q11.2 deletion syndrome: An MRI analysis

There are limited MRI studies of craniofacial and velopharyngeal features in children with 22q11.2 deletion syndrome (22q11.2DS) and to date, none have explored the potential relationship between these features and the speech phenotype. The purpose of this study was to examine the relationship between craniofacial and related velopharyngeal structures in children with 22q11.2DS and to assess their correlation to resonance features using an unsedated MRI protocol. Fifteen children with 22q11.2DS and 15 age- and sex-matched controls with normal velopharyngeal anatomy (ages 4-12 years) successfully completed the study. Analysis of covariance was used to compare differences between the experimental (22q11.2DS) and control (children with normal anatomy) groups. Correlation analyses and regression models were also utilized. The 22q11.2DS group demonstrated significantly shorter nasion-to-sella, sella-to-basion, and basion-to-opisthion distances. The anterior cranial base angle was significantly more obtuse. The levator veli palatini (levator) muscle was significantly thinner and shorter, with an obtuse angle of origin in the 22q11.2DS group. Levator length was significantly correlated with the sella-to-basion measure and hypernasality was correlated with levator origin-to-origin distance. Preliminary results from this study indicate a significant association between hypernasality and levator origin-to-origin distance. Findings from the present study, provide an insight into the pathophysiology of velopharyngeal dysfunction related to this clinically complex population.

Differences in the Tensor Veli Palatini Muscle and Hearing Status in Children With and Without 22q11.2 Deletion Syndrome

PURPOSE

To investigate the dimensions of the tensor veli palatini (TVP) muscle using high image resolution 3-dimensional magnetic resonance imaging (MRI) of the soft palate among children with normal velopharyngeal and craniofacial anatomy and to compare values to individuals with a diagnosis of 22q11.2 deletion syndrome (22q11DS). We also sought to determine whether there is a relationship between hypoplasia of the TVP and severity of middle ear dysfunction and hearing loss.

METHODS

Three-dimensional MRI were used to collect and analyze data obtained across 53 children between 4 and 12 years of age, including 40 children with normal velopharyngeal and craniofacial anatomy and 13 children with a diagnosis of 22q11.2 DS. Tensor veli palatini muscle length, thickness, and volume as well as bihamular distance were compared among participant groups.

RESULTS

A Welch's t-test revealed that the TVP in participants with 22q11DS is significantly shorter (P = .005, 17.3 vs 19.0 mm), thinner (P < .001, 1.1 vs 1.8 mm), and less voluminous (P < .001, 457.5 vs 667.3 mm³) than participants without 22q11DS. Participants with 22q11DS also had a greater (P = .006, 27.7 vs 24.7 mm) bihamular distance than participants without 22q11DS. There was an inverse relationship between TVP abnormalities noted above and the severity of audiologic and otologic histories.

CONCLUSION

The TVP muscle is substantially reduced in volume, length, and thickness in children with 22q11DS. These findings serve as preliminary support for the association of patient hearing and otologic severity and TVP dysmorphology.

Velopharyngeal Structural and Muscle Variations in Children With 22q11.2 Deletion Syndrome: An Unsedated MRI Study

Objective:

The 22q11.2 deletion syndrome (22q11.2DS) is the most common genetic cause of velopharyngeal dysfunction; however, limited information exists regarding variations in velopharyngeal anatomy in this clinically challenging population. The purpose of this study was to examine velopharyngeal characteristics among young children with 22q11.2DS in comparison to a normative cohort using an innovative, nonsedated magnetic resonance imaging (MRI) scanning protocol.

Methods:

Fifteen children with 22q11.2DS and 15 age- and gender-matched controls with normal velopharyngeal anatomy (ages 4-12) successfully completed the MRI protocol. Eighteen velopharyngeal and 2 related craniofacial measures were examined. Analysis of covariance was used to compare differences between the experimental and the control groups.

Results:

The 22q11.2DS group demonstrated a significantly thinner velum ( P < .0005) and a larger pharyngeal depth ( P = .007) compared to the matched control group. Findings in the current study also demonstrated that the levator veli palatini muscle is significantly shorter ( P = .037) and thinner ( P = .025) in the 22q11.2DS cohort, with a significantly shorter origin-to-origin distance ( P < .0005) and a greater angle of origin ( P = .001) compared to healthy peers.

Conclusion:

Children with 22q11.2DS demonstrated multiple variations that may contribute to velopharyngeal dysfunction by altering the anatomic characteristics of the velopharyngeal port, the levator muscle, and associated structures. This investigation represents the first and largest attempt to characterize velopharyngeal anatomy in children with 22q11.2DS using a nonsedated MRI protocol.