Incorporating Velopharyngeal MRI into the Clinical Decision-Making Process for a Patient Presenting with Velopharyngeal Dysfunction Following a Failed Palatoplasty

This clinical report describes the implementation of magnetic resonance imaging (MRI) to evaluate a patient with long-standing velopharyngeal dysfunction. She was referred to the craniofacial clinic at age 10 with no prior surgical history and subsequently completed a Furlow palatoplasty due to a suspected submucous cleft palate. However, results were unfavorable with minimal improvement in speech or resonance. The clinical presentation, treatment, outcomes, and contributions from MRI for secondary surgical planning are described. Addition of MRI into the clinical workflow provided insights into the anatomy and physiology of the velopharyngeal mechanism that were unable to be obtained from nasendoscopy and speech evaluation alone.

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.

Establishing a Clinical Protocol for Velopharyngeal MRI and Interpreting Imaging Findings

Traditional imaging modalities used to assess velopharyngeal insufficiency (VPI) do not allow for direct visualization of underlying velopharyngeal (VP) structures and musculature which could impact surgical planning. This limitation can be overcome via structural magnetic resonance imaging (MRI), the only current imaging tool that provides direct visualization of salient VP structures. MRI has been used extensively in research; however, it has had limited clinical use. Factors that restrict clinical use of VP MRI include limited access to optimized VP MRI protocols and uncertainty regarding how to interpret VP MRI findings. The purpose of this paper is to outline a framework for establishing a novel VP MRI scan protocol and to detail the process of interpreting scans of the velopharynx at rest and during speech tasks. Additionally, this paper includes common scan parameters needed to allow for visualization of velopharynx and techniques for the elicitation of speech during scans.

Velopharyngeal Characteristics in Aarskog-Scott Syndrome: A Case Report

Aarskog-Scott syndrome (AAS), also known as facio-digito-genital syndrome, is a rare heterogenous syndrome characterized by facial dysmorphism, brachydactyly, and genetic abnormalities. Although severe craniofacial abnormalities have been reported in AAS, little is known about speech and resonance issues in AAS. Specifically, published data to date have only indicated reports of hypernasality associated with a cleft palate in AAS. This case report provides clinical and anatomic information surrounding hypernasal speech in the absence of an overt cleft palate in a patient with AAS.

Outcomes of primary repair of cleft palate using sommerled intravelar veloplasty associated with velocardiofacial syndrome

OBJECTIVES

Velocardiofacial syndrome, a prevalent microdeletion syndrome occurring in 1 in 2000-4000 live births, is marked by speech and language disorders, notably velopharyngeal dysfunction. This study investigates speech outcomes, nasometric and videofluoroscopic results before and after primary repair of cleft palate using the Sommerlad intravelar veloplasty (SIVV) technique within the Isfahan cleft care team for patients with velocardiofacial syndrome.

METHODS

Employing a quasi-experimental design, 19 participants with velocardiofacial syndrome, who underwent primary cleft palate repair by the Isfahan cleft care team, were included through convenience sampling. Perceptual and instrumental outcomes were assessed pre-and post-operatively. Statistical analysis encompassed paired t-tests and the non-parametric Wilcoxon signed-rank test (p < 0.05).

RESULTS

The study identified no statistically significant differences between pre-and post-surgical speech outcome parameters and nasalance scores. Nonetheless, a significant distinction emerged in the velopharyngeal closure ratio based on fluoroscopic evaluation (p = 0.038).

CONCLUSION

The efficacy of the SIVV technique in treating velopharyngeal dysfunction in velocardiofacial syndrome patients is inconclusive, demanding further research. Post-surgical speech outcomes are influenced by surgical technique, hypotonia, apraxia of speech, and surgery timing. Notably, an elevated velopharyngeal valve closure ratio, though anatomically indicative, does not exclusively predict surgical success.

Surgical Management of Submucous Cleft Palate by Radical Muscle Dissection Veloplasty: Speech Outcomes in Patients with 22q11.2 Deletion Syndrome

OBJECTIVE

To evaluate the benefit of anatomical muscle dissection repair for velopharyngeal insufficiency (VPI) in patients with submucous cleft palate (SMCP) with 22q11.2 deletion syndrome.

DESIGN

Retrospective blinded randomised analysis of a surgeon's management over 10 years.

SETTING

The study was performed at a specialised Paediatric hospital in the United Kingdom.

PATIENTS

Children with SMCP and 22q11.2 deletion syndrome.

INTERVENTIONS

All participants underwent radical muscle dissection veloplasty.

OUTCOMES MEASURED

Pre- and post- operative measurements included severity of anatomical defect, speech samples and lateral images which were digitised, randomised then externally and blindly analysed using validated techniques. Stata software was used to perform statistical analysis.

RESULTS

57 children with 22q11.2 deletion syndrome were included in this analysis. Intra-operatively, the majority of cases were identified as SMCP Grade I anomalies. Post-operatively, a statistically significant improvement in hypernasality, resting palate length, palate length at maximum closure, palate excursion and gap size at maximum closure was observed. Secondary surgery was performed for 59% of patients by ten years.

CONCLUSION

Muscle dissection repair improves hypernasality, palate closure function and the closure gap in patients with 22q11.2 deletion syndrome. Although over 50% of patients may require further surgery, muscle dissection repair should be a first step due to its utility at a younger age, when invasive investigations are impossible, its lower morbidity, speech and language benefits or altering the plans for less obstructive secondary surgery when it lead to reduced velo-pharyngeal gap and improved palate mobility even when adequate velo-pharyngeal closure was not achieved.

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.

The Pediatric Neuroradiologist's Practical Guide to Capture and Evaluate Pre- and Postoperative Velopharyngeal Insufficiency

Up to 30% of children with cleft palate will develop a severe speech disorder known as velopharyngeal insufficiency. Management of velopharyngeal insufficiency typically involves structural and functional assessment of the velum and pharynx by endoscopy and/or videofluoroscopy. These methods cannot provide direct evaluation of underlying velopharyngeal musculature. MR imaging offers an ideal imaging method, providing noninvasive, high-contrast, high-resolution imaging of soft-tissue anatomy. Furthermore, focused-speech MR imaging techniques can evaluate the function of the velum and pharynx during sustained speech production, providing critical physiologic information that supplements anatomic findings. The use of MR imaging for velopharyngeal evaluation is relatively novel, with limited literature describing its use in clinical radiology. Here we provide a practical approach to perform and interpret velopharyngeal MR imaging examinations. This article discusses the velopharyngeal MR imaging protocol, methods for interpreting velopharyngeal anatomy, and examples illustrating its clinical applications. This knowledge will provide radiologists with a new, noninvasive tool to offer to referring specialists.

Diagnosing and Managing Velopharyngeal Insufficiency in Patients With Cleft Palate After Primary Palatoplasty

Velopharyngeal insufficiency (VPI) after palatoplasty is caused by improper anatomy preventing velopharyngeal closure and manifests as a hypernasal resonance, audible nasal emissions, weak pressure consonants, compensatory articulation, reduced speech loudness, and nostril or facial grimacing. A multidisciplinary team using multimodal instruments (speech analysis, nasoendoscopy, videofluoroscopy, nasometry, and magnetic resonance imaging) to evaluate velopharyngeal function should manage these patients. Careful monitoring of velopharyngeal function by a speech pathologist remains paramount for early identification of VPI and the perceptual assessment should follow a standardized protocol. The greatest methodology problem in CLP studies has been the use of highly variable speech samples making comparison of published results impossible. It is hoped that ongoing international collaborative efforts to standardize procedures for collection and analysis of perceptual data will help this issue. Speech therapy is the mainstay treatment for velopharyngeal mislearning and compensatory articulation, but it cannot improve hypernasality, nasal emissions, or weak pressure consonants, and surgery is the definitive treatment for VPI. Although many surgical methods are available, there is no conclusive data to guide procedure choice. The goal of this review article is to present a review of established diagnostic and management techniques of VPI.

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.

Can Velopharyngeal MRI be Used in Individuals with Orthodontic Devices?

OBJECTIVE

To evaluate the influence of common pediatric orthodontic appliances on velopharyngeal (VP) MRI and to compare MR image sequences to determine if sequence parameters impact the visibility of key VP structures commonly assessed in clinical VP MRI.

DESIGN

Participants undergoing orthodontic treatment completed a VP MRI study. Level of distortion caused by orthodontic devices on 8 anatomical sites of interest and using variable MRI sequences was evaluated.

SETTING

Single institution.

PARTICIPANTS

Nineteen participants undergoing orthodontic treatment.

MAIN OUTCOME

Level of distortion caused by metal artifacts and MR sequence used.

RESULTS

The results of this study demonstrate that appliances such as hyrax palatal expanders and braces with stainless steel brackets are acceptable for a VP MRI, while class II corrector springs are not recommended. The HASTE MRI sequence with 2D imaging techniques should be utilized if the child has orthodontic devices, while FSE and 3D imaging techniques are not recommended. The presence of wire spring coils and molar bands are likely to not to interfere with the MRI evaluation.

CONCLUSIONS

Findings from this study suggest that the presence of orthodontic appliances does not hinder visualization of all velopharyngeal structures during an MRI. Therefore, careful consideration must be made prior to disqualifying or recommending patients for VP MRI.

Preliminary Development of an MRI Atlas for Application to Cleft Care: Findings and Future Recommendations

OBJECTIVE

To introduce a highly innovative imaging method to study the complex velopharyngeal (VP) system and introduce the potential future clinical applications of a VP atlas in cleft care.

DESIGN

Four healthy adults participated in a 20-min dynamic magnetic resonance imaging scan that included a high-resolution T2-weighted turbo-spin-echo 3D structural scan and five custom dynamic speech imaging scans. Subjects repeated a variety of phrases when in the scanner as real-time audio was captured.

SETTING

Multisite institution and clinical setting.

PARTICIPANTS

Four adult subjects with normal anatomy were recruited for this study.

MAIN OUTCOME

Establishment of 4-D atlas constructed from dynamic VP MRI data.

RESULTS

Three-dimensional dynamic magnetic resonance imaging was successfully used to obtain high quality dynamic speech scans in an adult population. Scans were able to be re-sliced in various imaging planes. Subject-specific MR data were then reconstructed and time-aligned to create a velopharyngeal atlas representing the averaged physiological movements across the four subjects.

CONCLUSIONS

The current preliminary study examined the feasibility of developing a VP atlas for potential clinical applications in cleft care. Our results indicate excellent potential for the development and use of a VP atlas for assessing VP physiology during speech.

Nonsedated Magnetic Resonance Imaging for Visualization of the Velopharynx in the Pediatric Population

BACKGROUND

Non-sedated MRI is gaining traction in clinical settings for visualization of the velopharynx in children with velopharyngeal insufficiency. However, the behavioral adaptation and training aspects that are essential for successful pediatric MRI have received limited attention.

SOLUTION

We outline a program of behavioral modifications combined with patient education and provider training that has led to high success rates for non-sedated velopharyngeal MRI in children.

An Exploratory Investigation of the Palatoglossus Muscle in Children Using Magnetic Resonance Imaging

PURPOSE

There is currently little evidence reporting the typical morphology of the palatoglossus (PG) muscle. The primary purpose of this exploratory study is to determine whether magnetic resonance imaging (MRI) methods used to quantify the morphology of the levator veli palatini (LVP) muscle can be applied to the PG. The secondary purpose is to provide preliminary data regarding the relationship between the LVP and PG muscles in children.

METHOD

Ten children between ages of 4 and 7 years participated in this study. Each participant was scanned using a nonsedated, child-friendly protocol with a T2-weighted, three-dimensional anatomical scan to obtain images of the oropharyngeal anatomy. Custom, oblique-coronal image planes were created to visualize and measure the LVP and PG muscles in their entirety from origin to insertion. Thermo Scientific Amira Software was used to obtain 2D measurements of PG muscle length, width, velar insertion distance, lingual insertion distance, and several angle measurements.

RESULTS

The PG ranged from 17.95 to 26.96 mm in length across participants. Velar insertion distance ranged from 17.22 to 30.95 mm. Lingual insertion distance ranged from 26.91 to 36.02 mm. Width ranged from 2.32 to 3.08 mm. The angle formed by the PG and LVP muscle planes ranged from 7.3° to 52.7°. The LVP insertion angle ranged from 42.5° to 75.9°. The PG insertion angle ranged from 16.9° to 52.3°.

CONCLUSIONS

MRI was successful in visualizing the PG muscle. The PG was consistent in size and shape within an individual participant but varied across the participant cohort.

Single cell multi-omic analysis identifies a Tbx1-dependent multilineage primed population in murine cardiopharyngeal mesoderm

The poles of the heart and branchiomeric muscles of the face and neck are formed from the cardiopharyngeal mesoderm within the pharyngeal apparatus. They are disrupted in patients with 22q11.2 deletion syndrome, due to haploinsufficiency of TBX1, encoding a T-box transcription factor. Here, using single cell RNA-sequencing, we now identify a multilineage primed population within the cardiopharyngeal mesoderm, marked by Tbx1, which has bipotent properties to form cardiac and branchiomeric muscle cells. The multilineage primed cells are localized within the nascent mesoderm of the caudal lateral pharyngeal apparatus and provide a continuous source of cardiopharyngeal mesoderm progenitors. Tbx1 regulates the maturation of multilineage primed progenitor cells to cardiopharyngeal mesoderm derivatives while restricting ectopic non-mesodermal gene expression. We further show that TBX1 confers this balance of gene expression by direct and indirect regulation of enriched genes in multilineage primed progenitors and downstream pathways, partly through altering chromatin accessibility, the perturbation of which can lead to congenital defects in individuals with 22q11.2 deletion syndrome.

Deep-learning-based segmentation of the vocal tract and articulators in real-time magnetic resonance images of speech

BACKGROUND AND OBJECTIVE

Magnetic resonance (MR) imaging is increasingly used in studies of speech as it enables non-invasive visualisation of the vocal tract and articulators, thus providing information about their shape, size, motion and position. Extraction of this information for quantitative analysis is achieved using segmentation. Methods have been developed to segment the vocal tract, however, none of these also fully segment any articulators. The objective of this work was to develop a method to fully segment multiple groups of articulators as well as the vocal tract in two-dimensional MR images of speech, thus overcoming the limitations of existing methods.

METHODS

Five speech MR image sets (392 MR images in total), each of a different healthy adult volunteer, were used in this work. A fully convolutional network with an architecture similar to the original U-Net was developed to segment the following six regions in the image sets: the head, soft palate, jaw, tongue, vocal tract and tooth space. A five-fold cross-validation was performed to investigate the segmentation accuracy and generalisability of the network. The segmentation accuracy was assessed using standard overlap-based metrics (Dice coefficient and general Hausdorff distance) and a novel clinically relevant metric based on velopharyngeal closure.

RESULTS

The segmentations created by the method had a median Dice coefficient of 0.92 and a median general Hausdorff distance of 5mm. The method segmented the head most accurately (median Dice coefficient of 0.99), and the soft palate and tooth space least accurately (median Dice coefficients of 0.92 and 0.93 respectively). The segmentations created by the method correctly showed 90% (27 out of 30) of the velopharyngeal closures in the MR image sets.

CONCLUSIONS

An automatic method to fully segment multiple groups of articulators as well as the vocal tract in two-dimensional MR images of speech was successfully developed. The method is intended for use in clinical and non-clinical speech studies which involve quantitative analysis of the shape, size, motion and position of the vocal tract and articulators. In addition, a novel clinically relevant metric for assessing the accuracy of vocal tract and articulator segmentation methods was developed.

Velopharyngeal Muscle Morphology in Children With Unrepaired Submucous Cleft Palate: An Imaging Study

OBJECTIVE

To identify quantitative and qualitative differences in the velopharyngeal musculature and surrounding structures between children with submucous cleft palate (SMCP) and velopharyngeal insufficiency (VPI) and noncleft controls with normal anatomy and normal speech.

METHODS

Magnetic resonance imaging was used to evaluate the velopharyngeal mechanism in 20 children between 4 and 9 years of age; 5 with unrepaired SMCP and VPI. Quantitative and qualitative measures of the velum and levator veli palatini in participants with symptomatic SMCP were compared to noncleft controls with normal velopharyngeal anatomy and normal speech.

RESULTS

Analysis of covariance revealed that children with symptomatic SMCP demonstrated increased velar genu angle (15.6°, P = .004), decreased α angle (13.2°, P = .37), and longer (5.1 mm, P = .32) and thinner (4 mm, P = .005) levator veli palatini muscles compared to noncleft controls. Qualitative comparisons revealed discontinuity of the levator muscle through the velar midline and absence of a musculus uvulae in children with symptomatic SMCP compared to noncleft controls.

CONCLUSIONS

The levator veli palatini muscle is longer, thinner, and discontinuous through the velar midline, and the musculus uvulae is absent in children with SMCP and VPI compared to noncleft controls. The overall velar configuration in children with SMCP and VPI is disadvantageous for achieving adequate velopharyngeal closure necessary for nonnasal speech compared to noncleft controls. These findings add to the body of literature documenting levator muscle, musculus uvulae, and velar and craniometric parameters in children with SMCP.

Identifying Predictors of Levator Veli Palatini Muscle Contraction During Speech Using Dynamic Magnetic Resonance Imaging

Purpose The purpose of this study was to identify predictors of levator veli palatini (LVP) muscle shortening and maximum contraction velocity in adults with normal anatomy. Method Twenty-two Caucasian English-speaking adults with normal speech and resonance were recruited. Participants included 11 men and 11 women (M = 22.8 years, SD = 4.1) with normal anatomy. Static magnetic resonance images were obtained using a three-dimensional static imaging protocol. Midsagittal and oblique coronal planes were established for visualization of the velum and LVP muscle at rest. Dynamic magnetic resonance images were obtained in the oblique coronal plane during production of "ansa." Amira 6.0.1 Visualization and Volume Modeling Software and MATLAB were used to analyze images and calculate LVP shortening and maximum contraction velocity. Results Significant predictors (p < .05) of maximum LVP shortening during velopharyngeal closure included mean extravelar length, LVP origin-to-origin distance, velar thickness, pharyngeal depth, and velopharyngeal ratio. Significant predictors (p < .05) of maximum contraction velocity during velopharyngeal closure included mean extravelar length, intravelar length, LVP origin-to-origin distance, and velar thickness. Conclusions This study identified six velopharyngeal variables that predict LVP muscle function during real-time speech. These predictors should be considered among children and individuals with repaired cleft palate in future studies.

Contracted Extravelar Segments of the Levator Veli Palatini Muscle: A Magnetic Resonance Imaging Morphometric Study

OBJECTIVES

To provide detailed descriptions of contraction-induced morphometric changes in the extravelar segments of the levator veli palatini (LVP) muscle using 3-dimensional (3-D) magnetic resonance imaging (MRI).

DESIGN

Three-dimensional MRI data were acquired at rest and during "silent /i/" from 4 singers. During silent /i/, participants voluntarily sustained velar elevation while breathing orally for the entire scan time. Focusing on the extravelar segments, LVP length, angle of the muscle origin, and cross-sectional area (CSA), measurements were obtained and compared between tasks.

RESULTS

Three of the 4 participants exhibited the expected patterns of change following concentric contraction of the LVP muscle. Consistent changes from the resting to the contracted state included reductions in LVP length by 13.5% and angle of the muscle origin by 9.8%, as well as increases in CSAs by 22.1%, on average.

CONCLUSIONS

This study presented high-resolution data of the LVP muscle behavior with the first in vivo 3-D measurements of the contracted LVP muscle, which can be useful for the validation of computational models that aim at describing biomechanical properties of the LVP muscle in future research. The active behavior of the extravelar LVP muscle also provides some insight on optimal LVP muscle geometry to consider during cleft palate repair.

Impact of Cranial Base Abnormalities on Cerebellar Volume and the Velopharynx in 22q11.2 Deletion Syndrome

OBJECTIVE

The purpose of this study was to analyze the relationship between cranial base, cerebellar, craniofacial, and velopharyngeal (VP) variables in individuals with 22q11.2 deletion syndrome (22q11DS).

METHODS

Thirteen typically developing healthy children and 13 age- and sex-matched individuals with 22q11DS completed a magnetic resonance imaging scan, which was used to examine craniofacial and VP variables.

RESULTS

A statistically significant difference was noted in cerebellum volumes, F_1,24 = 7.947, P = .010, posterior nasal spine to posterior pharyngeal wall (PNS-PPW), F_1,24 = 4.878, P = .037, nasion-sella-basion (NSB) cranial base angles, F_1,24 = 7.253, P = .013, and sella-basion-opisthion (SBO) cranial base angles, F_1,24 = 9.134, P = .006, between children with 22q11DS and controls. The cerebellum volume was significantly reduced and cranial base angles were significantly more obtuse in individuals with 22q11DS. In the 22q11DS group, cerebellum volume was significantly correlated with sella-basion (SB) length, osseous pharyngeal depth, the PNS-PPW length, and velar length (P < .05). The PNS-PPW length was correlated with SB length, basion-opisthion length, NSB angle, SBO angle, and the VP ratio (P < .05).

CONCLUSION

This study supports previous findings on anatomical differences among individuals with 22q11DS and has expanded our current understanding of the potential relationship between craniofacial and VP variables in at least a subset of children with 22q11DS. Results provide preliminary insights into the potential relationship between a decrease in cerebellar volume, obtuse cranial base angles, and unfavorable VP dimensions.

Suckling, Feeding, and Swallowing: Behaviors, Circuits, and Targets for Neurodevelopmental Pathology

All mammals must suckle and swallow at birth, and subsequently chew and swallow solid foods, for optimal growth and health. These initially innate behaviors depend critically upon coordinated development of the mouth, tongue, pharynx, and larynx as well as the cranial nerves that control these structures. Disrupted suckling, feeding, and swallowing from birth onward-perinatal dysphagia-is often associated with several neurodevelopmental disorders that subsequently alter complex behaviors. Apparently, a broad range of neurodevelopmental pathologic mechanisms also target oropharyngeal and cranial nerve differentiation. These aberrant mechanisms, including altered patterning, progenitor specification, and neurite growth, prefigure dysphagia and may then compromise circuits for additional behavioral capacities. Thus, perinatal dysphagia may be an early indicator of disrupted genetic and developmental programs that compromise neural circuits and yield a broad range of behavioral deficits in neurodevelopmental disorders.