Search

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. [ABSTRACT FROM AUTHOR]

The levator veli palatini (LVP) muscle drives the elevation and retraction of the soft palate to facilitate speech and feeding, but undergoes atrophic changes in patients with cleft palate deformity. This study aimed to establish an effective drug delivery technique for LVP muscle regeneration. An intraoral injection technique for rat LVP muscle regeneration was developed based on careful examination of the rat craniofacial anatomy. The accuracy and reliability of this technique were tested by cone-beam computed tomography and nitrocellulose dye labeling. Recombinant human Wnt7a was delivered via this injection technique, and the subsequent responses of the levator veli palatini muscle were analyzed. Both the cone-beam computed tomography orientation of the needle tip and dye labeling suggested repeatable accuracy of the injection technique. Recombinant human Wnt7a delivery via this technique induced regeneration-related changes, including increased expression of centrally nucleated myofibers and Ki67+ve nuclei. The intraoral injection technique is safe and efficient. It can be used for accurate drug delivery and to screen regenerative therapeutics for the LVP muscle. [ABSTRACT FROM AUTHOR]

Summary Aim To find out if subjects with 22q11.2 deletion syndrome (DS) have a different velopharyngeal anatomy which could cause velopharyngeal insufficiency (VPI). Methods A prospective study of 16 subjects >16 years of age with 22q11.2 DS, without overt cleft palate and without previous VPI surgery, and 48 healthy controls >18 years of age were included in the study. Speech was recorded and scored blindly by two independent senior speech therapists. All 64 individuals had MRI scans, which were analyzed blindly by a consultant radiologist. Results Subjects with 22q11.2 DS had a mild degree of weak pressure consonants (mean score); borderline to mild degree of hypernasality and audible nasal emission (mean score). All controls had normal speech. When comparing subjects (22q11.2 DS) to controls, we found the subjects to have the following: A shorter distance between left and right points of origin of the levator veli palatini muscle (LVP) ( p  < 0.0001); a more obtuse angle of origin of the LVP (bilaterally) ( p  < 0.009); a thinner LVP bilaterally and in the midline ( p  < 0.0001); a shorter LVP bilaterally ( p  < 0.0001); a shorter velum ( p  = 0.007); a larger osseous pharyngeal depth:velar length ratio ( p  = 0.01); a more obtuse anterior cranial base angle (nasion to sella to basion) ( p  < 0.0001) and posterior cranial base angle (sella to basion to foramen magnum) ( p  < 0.0001); a wider velopharyngeal width ( p  = 0.002) and a larger pharyngeal airway volume ( p  = 0.0007). Conclusion Compared with healthy controls, adults with 22q11.2 DS showed a different velopharyngeal anatomy, which will make these individuals more prone to VPI. [ABSTRACT FROM AUTHOR]