Does MRI contribute to the investigation of palatal function?

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.

Exploration of the Influences of Temporary Velum Paralysis on Auditory-Perceptual, Acoustic, and Tomographical Markers

Purpose To better understand hypernasality (HN), we explored the relations between velopharyngeal orifice, auditory perception of HN, and acoustic-spectral measures in an in vivo within-subject design: (a) with a normally functioning velum as the control condition and (b) with a temporarily paralyzed velum as the experimental condition. Method The velum of eight volunteers was injected with ropivacaine hydrochloride (Naropin) in the area of the levator veli palatini and tensor veli palatini muscles to induce temporary velopharyngeal inadequacy (VPI) and HN. Sustained [a] and [i] and oronasal text readings were recorded, and 3D cone-beam computed tomography images of the vocal tract were built before and during velar anesthesia. Differences between conditions and correlations in normal-to-numb differences between velopharyngeal cross-sectional area (VP_area), mean ratings of HN severity, and nine acoustic-spectral measures were determined. Results Three subjects already had some incomplete velopharyngeal closure in the control condition. Temporary motor nerve blockage of the velum (increased VP_area) was accomplished in seven subjects, leading to increased HN and changes in three acoustic-spectral measures. Furthermore, significant correlations only emerged between VP_area, HN, and Model_Kataoka. Conclusions In most of the participants, it was possible to temporarily increase the velopharyngeal orifice to investigate HN while controlling other speech variables and cephalic morphology. Although this study was exploratory and its are findings preliminary, it provided additional evidence for the possible clinical value of Model_Kataoka, A ₃-P ₀, and B _F1 for the objective measurement of VPI or HN.

Comparison of Real-Time Speech Magnetic Resonance Imagings With Perceptual Speech Analysis in Evaluation Velopharyngeal Sphincter Function

ABSTRACT

Identifying substantial data and their normative values related to velopharyngeal structures in cleft palate patients may have clinical significance, in order to selection of surgical intervention and prediction of postsurgical outcomes. Previous studies are lack of referring certain anatomic locations or distances that may have affect on speech intelligibility, especially in dynamic state. The aim of this study is to investigate effectiveness of magnetic resonance imagings on the velopharyngeal sphincter function and the correlation with speech intelligibility after functional cleft palate repair. Seventeen patients with repaired cleft palate by single surgeon were enrolled in this study.Quantitative velopharyngeal measures from the oblique coronal plane and midsagittal plane in static and dynamic positions were collected. Patients' speech intelligibility was evaluated by using Pittsburgh Weighted Speech Scale and nasalance score was also measured. Correlation analysis methods were used for evaluating relation between MRI gathered measurements and speech intelligibility scores for determiningconsequential data.Our study shows that the velar knee-posterior pharyngeal wall distance measurement while explosive sound production is the most related data with speech intelligibility. Although future works with more sample number is needed, according to current study the authors think magnetic resonance imagings is a very helpful method in providing reliable information.

Dynamic Analysis of Articulatory Movement Using Magnetic Resonance Imaging Movies: Methods and Implications in Cleft Lip and Palate

Objectives

To visualize articulatory movement using a magnetic resonance imaging (MRI) movie of a subject with cleft lip and palate (CLP) and to demonstrate the usefulness of this method for studying oropharyngeal function.

Material and Methods

Dynamic changes in oropharyngeal structures were assessed with an MRI movie of a man with cleft lip and palate and in a normal adult male volunteer during the articulation of /pa/, /ta/, and /ka/.

Results and Conclusions

Different movement patterns were observed during articulation in the subject with CLP compared with the normal volunteer. Posterosuperior movement of the tongue and the anterior movement of the posterior pharyngeal wall were clearly visualized in the subject with CLP. Thus, MRI movies appear to be a promising tool for evaluating speech function in patients with CLP because of their noninvasive and nonradiation nature.

Magnetic Resonance Imaging of the Levator Veli Palatini Muscle before and after Primary Palatoplasty

Objective

To explore the application of magnetic resonance imaging (MRI) in the evaluation of patients with cleft palate before and after primary palatoplasty with particular attention focused on the levator veli palatini muscle.

Design

Prospective study using MRIs of subjects before and after primary cleft palate surgery.

Setting

Hospital and university based.

Patients

One female infant with normal anatomy. Three male and four female infants with cleft palate of varying severity.

Intervention

Furlow double-opposing Z-plasty and V-Y palatoplasty.

Main Outcome Measures

Magnetic resonance images.

Results

It was found that the levator veli palatini muscle can be imaged before and after palatal surgery in infants using MRI. The muscle may have sufficient volume, proportionate to a normal infant or adult, in infants born with cleft palate. If retrodisplaced properly, the muscle is likely to be steeper (more vertical) from its origin at the base of the skull to its insertion into the velum following palatoplasty, thus providing a more favorable angle for elevating the velum. Following palatal surgery, the levator muscle mass may not be as cohesive across the velar midline, compared with normal musculature.

Conclusion

MRI is a viable imaging modality for the evaluation of the anatomy of the levator veli palatini muscle before and after primary palatoplasty in infants born with cleft palate.

Can Dynamic MRI Be Used to Accurately Identify Velopharyngeal Closure Patterns?

BACKGROUND

Dynamic magnetic resonance imaging (MRI) has been proposed as a non-invasive, child-friendly, reproducible, and repeatable imaging method providing a 3-dimensional view of the velopharyngeal structures and function during speech. However, the value of dynamic MRI as compared to imaging methods such as nasopharyngoscopy is not well understood. The aim of this study was to compare the ability of nasopharyngoscopy and dynamic MRI to accurately identify velopharyngeal closure patterns among adults without cleft palate.

METHODS

Participants included 34 healthy adults with normal anatomy between 19 and 33 years of age (mean = 23 years; SD = 4.1 years). Participants underwent dynamic MRI and nasopharyngoscopy studies and comparisons were performed to determine the intra- and inter-rater reliability for accurately determining closure pattern. The MRI acquisition was a dynamic acquisition of a 2D plane.

RESULTS

Strong inter- (κ = .824; P < .001) and intra-rater (Rater 1: κ = 0.879, P < .001, 94% agreement between ratings; Rater 2 with 100% agreement) agreement was observed for the identification of closure pattern using nasopharyngoscopy. Inter-rater agreement for ratings using MRI demonstrated moderate agreement (κ = .489; P < .004). Examining point agreement revealed only 27 of the 33 ratings of MRI showed agreement (80%).

CONCLUSION

This demonstrates that inter-rater reliability for determining closure patterns from nasopharyngoscopy is good; however, ratings using MRI was less reliable at determining closure patterns. It is likely that future improvements in dynamic imaging with MRI to enable 3D visualizations are needed for improved diagnostic accuracy for assessing velopharyngeal closure patterns.

Velopharyngeal Structural and Functional Assessment of Speech in Young Children Using Dynamic Magnetic Resonance Imaging

OBJECTIVE

The purpose of this study was to demonstrate a novel method for examining the velopharyngeal mechanism using static and dynamic magnetic resonance imaging (MRI) at the sentence-level production in young children with normal anatomy. This study examined whether velopharyngeal events occurring in the midsagittal plane are correlated to muscle events occurring along the plane of velopharyngeal closure. Adenoid involvement in velopharyngeal function was also explored.

METHODS

A high-resolution, T2-weighted turbo-spin-echo three-dimensional anatomical scan was used to acquire static velopharyngeal data and a fast-gradient echo fast low angle shot multishot spiral technique (15.8 frames per second) was used to acquire dynamic data on 11 children between 4 and 9 years old.

RESULTS

Changes in velar knee height from rest to the bilabial /p/ production was strongly correlated with changes in the velar configuration (r = 0.680, P = .021) and levator muscle contraction (r = 0.703, P = .016). Velar configuration was highly correlated to levator muscle changes (r = 0.685, P = .020). Mean alpha angle during bilabial /p/ production was 176°, which demonstrated that subjects achieve velopharyngeal closure at or just below the palatal plane. Subjects with a larger adenoid pad used significantly less (r = -0.660, P = .027) levator muscle contraction compared with individuals with smaller adenoids.

CONCLUSIONS

This study demonstrates a potentially useful technique in dynamic MRI that does not rely on cyclic repetitions or sustained phonation. This study lends support to the clinical potential of dynamic MRI methods for cleft palate management.

Dynamic 1.5-T vs 3-T true fast imaging with steady-state precession (trueFISP)-MRI sequences for assessment of velopharyngeal function

OBJECTIVES

To compare the image quality of MRI scans produced with 1.5- and 3.0-T devices during functional test condition.

METHODS

65 MRI scans obtained with 1.5- (n = 43) or 3.0-T (n = 22) true fast imaging with steady-state precession (trueFISP) sequences from patients with a history of a cleft palate were evaluated. Two experts assessed the MRI scans, independently of each other, and blinded to the MRI technique used. Subjective ratings were entered on a five-point Likert scale. The median planes of three anatomical structures (velum, tongue and pharyngeal wall) were assessed in three functional states (at rest, during phonation of sustained "e" and during articulation of "kkk"). In addition, MRI scans taken during velopharyngeal closure were evaluated.

RESULTS

Under blinded conditions, both observers (radiologist and orthodontist) independently rated the quality of 1.5-T scans higher than that of 3.0 T. Statistical analysis of pooled data showed that the differences were highly significant (p < 0.009) in 4 out of 10 test conditions. The greatest differences in favour of 1.5 T were observed for MRI scans of the velum.

CONCLUSIONS

1.5 T used with trueFISP may be preferable over 3.0-T trueFISP for the evaluation of the velopharyngeal structures in the clinical routine.

Instrumental assessment of velopharyngeal function and resonance: a review

The purpose of this literature review is to describe and discuss instrumental assessment techniques of the velopharyngeal function in order to diagnose velopharyngeal disorders and resonance characteristics. Both direct and indirect assessment techniques are addressed, in which successively nasopharyngoscopy, videofluoroscopy, magnetic resonance imaging (MRI), cephalometric radiographic analysis, computed tomography (CT), ultrasound, acoustic and aerodynamic measurements are considered. Despite the multiple instrumental assessments available to detect and define velopharyngeal dysfunction, the ideal technique is not yet accessible. Therefore, a combination of different quantitative parameters can possibly form a solution for a more reliable determination of resonance disorders. These multi-dimensional approaches will be described and discussed. The combination of quantitative measurement techniques and perceptual evaluation of nasality will probably remain necessary to provide sufficient information to make appropriate decisions concerning the diagnosis and treatment of resonance disorders.

LEARNING OUTCOMES

The reader will be able to describe and discuss currently available instrumental techniques to assess the velopharyngeal mechanism and its functioning in order to diagnose velopharyngeal disorders. Additionally, he will be able to explain the possible advantages of the combination of several types of complementary measurement techniques.

Three-dimensional imaging methods for quantitative analysis of facial soft tissues and skeletal morphology in patients with orofacial clefts: a systematic review

Background

Current guidelines for evaluating cleft palate treatments are mostly based on two-dimensional (2D) evaluation, but three-dimensional (3D) imaging methods to assess treatment outcome are steadily rising.

Objective

To identify 3D imaging methods for quantitative assessment of soft tissue and skeletal morphology in patients with cleft lip and palate.

Data sources

Literature was searched using PubMed (1948–2012), EMBASE (1980–2012), Scopus (2004–2012), Web of Science (1945–2012), and the Cochrane Library. The last search was performed September 30, 2012. Reference lists were hand searched for potentially eligible studies. There was no language restriction.

Study selection

We included publications using 3D imaging techniques to assess facial soft tissue or skeletal morphology in patients older than 5 years with a cleft lip with/or without cleft palate. We reviewed studies involving the facial region when at least 10 subjects in the sample size had at least one cleft type. Only primary publications were included.

Data extraction

Independent extraction of data and quality assessments were performed by two observers.

Results

Five hundred full text publications were retrieved, 144 met the inclusion criteria, with 63 high quality studies. There were differences in study designs, topics studied, patient characteristics, and success measurements; therefore, only a systematic review could be conducted. Main 3D-techniques that are used in cleft lip and palate patients are CT, CBCT, MRI, stereophotogrammetry, and laser surface scanning. These techniques are mainly used for soft tissue analysis, evaluation of bone grafting, and changes in the craniofacial skeleton. Digital dental casts are used to evaluate treatment and changes over time.

Conclusion

Available evidence implies that 3D imaging methods can be used for documentation of CLP patients. No data are available yet showing that 3D methods are more informative than conventional 2D methods. Further research is warranted to elucidate it.

Systematic review registration

International Prospective Register of Systematic Reviews, PROSPERO CRD42012002041

Autologous Fat Injection Combined with Palatoplasty and Pharyngoplasty for Velopharyngeal Insufficiency and Cleft Palate

Objective

The aim was to evaluate clinical application of autologous fat transplantation in the posterior pharynx to treat velopharyngeal incompetence and cleft palate.

Study Design

Case series with chart review.

Setting

Cleft Lip and Palate Center of Plastic Surgery Hospital, an academic medical center.

Subjects and Methods

We studied 11 patients (age, 5-26 years) with a cleft palate and velopharyngeal insufficiency who underwent autologous fat injection. Patients were followed for 9 to 40 months. Pronunciation evaluation, visual appearance of the palatopharyngeal area, nasopharyngeal fibroscopy (NPF), palatopharyngeal lateral radiography, and magnetic resonance imaging (MRI) were undertaken before and after the operation.

Results

Speech intelligibility was markedly increased in all patients. Pronunciation was good to excellent compared with the preoperative level ( P = .001). Mean velopharyngeal insufficiency rate was significantly reduced from 26.05% to 6.96% ( P = .028) by NPF and from 26.42% to 7.11% ( P = .017) by MRI (axial plane). Magnetic resonance imaging indicated significantly reduced mean minimum velopharyngeal distance, from 10.39 to 3.65 mm ( P = .012) in the sagittal plane, and markedly increased thickness of transplanted fat in the posterior pharyngeal wall (sagittal, 5.43 mm; axial, 4.74 mm). There were few complications (sleep apnea, nasopharyngeal regurgitation).

Conclusion

Autologous fat transplantation in the posterior pharyngeal wall was a good method for treating velopharyngeal incompetence. The safety profile was good in our sample, and we got a consistent result in the follow-up period. In addition, it also could be combined with routine surgery.

Using MRI for assessing velopharyngeal structures and function

OBJECTIVE

Direct visualization of the velopharynx and, in particular, the levator muscle is particularly important in the assessment of velopharyngeal function and normal speech production. The purpose of this study is to demonstrate the development of a static and dynamic magnetic resonance imaging protocol for evaluation of velopharyngeal structures and function.

METHODS

A high-resolution, T2-weighted turbo-spin-echo three-dimensional anatomical scan (sampling perfection with application optimized contrasts using different flip angle evolution) was used to acquire a large field of view covering the velopharyngeal anatomy. Dynamic speech assessment was obtained using a fast-gradient echo, fast low-angle shot, multi-shot spiral technique to acquire 15.8 frames per second (FPS) of the sagittal and oblique coronal image planes.

RESULTS

Using a three-dimensional data set, as opposed to two-dimensional data, the full contour of the levator muscle can be appreciated. Dynamic images were obtained at 15.8 FPS in the sagittal and oblique coronal planes, enabling visualization of the movements of the velum, posterior pharyngeal wall, lateral pharyngeal walls, and levator muscle during speech.

CONCLUSIONS

A three-dimensional magnetic resonance imaging sequence, such as that used in the present study, may provide better analyses and more precise measurements. A dynamic fast low-angle shot sequence allows for visualization of the levator muscle and the velum during speech at a high image rate. This protocol could have a significant impact in improving the process of visualizing pathology and promoting clinical treatment plans for individuals born with cleft lip and palate.

Speech and magnetic resonance imaging results following autologous fat transplantation to the velopharynx in patients with velopharyngeal insufficiency

OBJECTIVE

To measure velopharyngeal closure with magnetic resonance imaging (MRI) and to evaluate speech when treating velopharyngeal insufficiency (VPI) with autologous fat transplantation to the velopharynx.

PATIENTS

Nine patients were recruited. Six patients had undergone cleft palate repair and subsequently developed VPI. Three were noncleft patients of which one had developed VPI after nasopharyngeal cancer treatment; another patient had developed VPI after combined adenotonsillectomy, and a third patient had VPI of unknown etiology.

MAIN OUTCOME MEASURE

Preoperative and 1-year postoperative MRIs were obtained during vocal rest and during phonation. Data measured were the velopharyngeal distance in the sagittal plane and the velopharyngeal gap area in the axial plane. Preoperative and 1-year postoperative audio recordings were blinded for scoring independently by three senior speech therapists.

RESULTS

When comparing preoperative and 1-year postoperative MRI during phonation we found a significant reduction of the median velopharyngeal distance from 4 to 0 mm (p = .011), and a significant reduction of the median velopharyngeal gap area from 42 to 34 mm(2) (p = .038). Nasal turbulence improved significantly (p = .011). Hypernasality/hyponasality and audible nasal emission did not change significantly.

CONCLUSIONS

Autologous fat transplantation to the velopharynx resulted in a significant reduction of the velopharyngeal distance and the velopharyngeal gap area during phonation, as measured by MRI. This was in accordance with a significant improvement in nasal turbulence. However, hypernasality and audible nasal emission did not change significantly and could not be correlated to the MRI findings.

Feasibility of dynamic MRI for evaluating velopharyngeal insufficiency in children

OBJECTIVE

To demonstrate the feasibility of dynamic MRI with near-real-time temporal resolution for analysing velopharyngeal closure.

METHODS

Eleven children and young adults (seven girls, four boys, mean age: 8.4 years) with suspected velopharyngeal insufficiency (VPI), and one healthy volunteer underwent MRI (1.5 Tesla) using T2 fast imaging sequences. Imaging was done without any sedation at rest and during various phonations in the axial and sagittal planes. Images were analysed by two radiologists, a plastic surgeon and a speech therapist.

RESULTS

The MRI examinations were well tolerated by even the youngest patient. A qualitative analysis found that the sagittal dynamic sequences during phonation were in relation to the clinical data in all patients. A quantitative analysis enabled calculation of the elevation angle of the soft palate in relation to the hard palate, the velar eminence angle and the percentage of reduction of the antero-posterior diameter of the pharyngeal lumen.

CONCLUSION

Dynamic MRI is a non-invasive, rapid and repeatable method. It can be considered a complementary tool to endoscopy and fluoroscopy, particularly in children, for assessing VPI without any sedation or radiation exposure.

Conscious sedation in pediatric speech endoscopy

OBJECTIVE

Speech nasoendoscopy is one of the gold standards for evaluating velopharyngeal insufficiency. The vast majority of pediatric patients are able to tolerate this procedure within the clinic under local anesthetic. However, a select group of pediatric patients is unable to cooperate with the examination. Conscious sedation is commonly used in pediatrics to aid in patient tolerance and cooperating with selected procedures. Conscious sedation has never been reported in the literature for use in speech endoscopy. The purpose of this study is to describe a technique for performing sedated speech endoscopy and to review our experience with sedated speech endoscopy in a selected group of patients who were unable to cooperate with examination under local anesthesia alone.

METHODS

A retrospective chart review was performed of pediatric patients between the ages of 2 and 15 who underwent conscious sedation for the speech nasoendoscopy. All examinations were performed at a tertiary care pediatric hospital. Sedation agent, tolerance of procedure, success of procedure, and complications associated with the procedure were recorded.

RESULTS

Fifty-seven sedated speech endoscopies were evaluated. Adequate examinations were obtained in 93% of patients overall and 100% of the patients evaluated while sedated with nitrous oxide. Complication rates and post-endoscopy speech management are reported.

CONCLUSIONS

Sedated speech endoscopy is a promising modality for evaluating velopharyngeal insufficiency in the pediatric population that may not otherwise be able to cooperate with examination in the clinic.

Velopharyngeal anatomy in 22q11.2 deletion syndrome: a three-dimensional cephalometric analysis

OBJECTIVE

22q11.2 deletion syndrome is the most common genetic cause of velopharyngeal dysfunction (VPD). Magnetic resonance imaging (MRI) is a promising method for noninvasive, three-dimensional (3D) assessment of velopharyngeal (VP) anatomy. The purpose of this study was to assess VP structure in patients with 22q11.2 deletion syndrome by using 3D MRI analysis.

DESIGN

This was a retrospective analysis of magnetic resonance images obtained in patients with VPD associated with a 22q11.2 deletion compared with a normal control group.

SETTING

This study was conducted at The Children's Hospital of Philadelphia, a pediatric tertiary care center.

PATIENTS, PARTICIPANTS

The study group consisted of 5 children between the ages of 2.9 and 7.9 years, with 22q11.2 deletion syndrome confirmed by fluorescence in situ hybridization analysis. All had VPD confirmed by nasendoscopy or videofluoroscopy. The control population consisted of 123 unaffected patients who underwent MRI for reasons other than VP assessment.

INTERVENTIONS

Axial and sagittal T1- and T2-weighted magnetic resonance images with 3-mm slice thickness were obtained from the orbit to the larynx in all patients by using a 1.5T Siemens Visions system.

OUTCOME MEASURES

Linear, angular, and volumetric measurements of VP structures were obtained from the magnetic resonance images with VIDA image-processing software.

RESULTS

The study group demonstrated greater anterior and posterior cranial base and atlanto-dental angles. They also demonstrated greater pharyngeal cavity volume and width and lesser tonsillar and adenoid volumes.

CONCLUSION

Patients with a 22q11.2 deletion demonstrate significant alterations in VP anatomy that may contribute to VPD.

Velopharyngeal anatomy in 22q11.2 deletion syndrome: a three-dimensional cephalometric analysis

OBJECTIVE

22q11.2 deletion syndrome is the most common genetic cause of velopharyngeal dysfunction (VPD). Magnetic resonance imaging (MRI) is a promising method for noninvasive, three-dimensional (3D) assessment of velopharyngeal (VP) anatomy. The purpose of this study was to assess VP structure in patients with 22q11.2 deletion syndrome by using 3D MRI analysis.

DESIGN

This was a retrospective analysis of magnetic resonance images obtained in patients with VPD associated with a 22q11.2 deletion compared with a normal control group.

SETTING

This study was conducted at The Children's Hospital of Philadelphia, a pediatric tertiary care center.

PATIENTS, PARTICIPANTS

The study group consisted of 5 children between the ages of 2.9 and 7.9 years, with 22q11.2 deletion syndrome confirmed by fluorescence in situ hybridization analysis. All had VPD confirmed by nasendoscopy or videofluoroscopy. The control population consisted of 123 unaffected patients who underwent MRI for reasons other than VP assessment.

INTERVENTIONS

Axial and sagittal T1- and T2-weighted magnetic resonance images with 3-mm slice thickness were obtained from the orbit to the larynx in all patients by using a 1.5T Siemens Visions system.

OUTCOME MEASURES

Linear, angular, and volumetric measurements of VP structures were obtained from the magnetic resonance images with VIDA image-processing software.

RESULTS

The study group demonstrated greater anterior and posterior cranial base and atlanto-dental angles. They also demonstrated greater pharyngeal cavity volume and width and lesser tonsillar and adenoid volumes.

CONCLUSION

Patients with a 22q11.2 deletion demonstrate significant alterations in VP anatomy that may contribute to VPD.

Trans-nasal endo-assisted pharyngoplasty: a cadaver study

A possible new technique of endoscopic pharyngoplasty is described and has been developed in cadavers. The trans-nasal route is used for endoscopic visualisation of the velopharyngeal sphincter. Hynes pharyngoplasty is performed using both trans-oral and trans-nasal routes. This approach allows better visualisation and performance of the Hynes pharyngoplasty at the desired level, "high" in the nasopharynx, without splitting the soft palate.

A new method for the study of velopharyngeal function using gated magnetic resonance imaging

The purpose of this project was to assess the feasibility of imaging the velopharynx of adult volunteers during repetitive speech, using gated magnetic resonance imaging (MRI). Although a number of investigators have used conventional MRI in the study of the human vocal tract, the mismatch between the lengthy time necessary to acquire sufficiently detailed images and the rapidity of movement of the vocal tract during speech has forced investigators to acquire images either while the subject is at rest or during sustained utterances. The technique used here acquired a portion of each image during repetitive utterances, building the full image over multiple utterance cycles. The velopharyngeal portal was imaged on a 1.5-Tesla GE Signa LX 8.2 platform with gated fast spoiled gradient echo protocol. An external 1-Hertz trigger was fed to the cardiac gate. Subjects synchronized utterance of consonant-vowel syllables to a flashing light synchronized with the external trigger. Each acquisition of 30 phases per second at a single-slice location took 22 to 29 seconds. Four consonant-vowel syllables (/pa/, /ma/, /sa/, and /ka/) were evaluated. Subjects vocalized throughout the acquisition, beginning 5 to 6 seconds beforehand to establish a regular rhythm. Imaging of the velopharyngeal portal was performed for sagittal, velopharyngeal axial (aligned perpendicular to the "knee" of the velum), axial, and coronal planes. Volumes were obtained by sequential acquisition of six to 10 slices (each with 30 phases) in the axial or sagittal planes during repetition of the /pa/ syllable. Spatiotemporal volumes of the single-slice data were sectioned to provide time-motion images (analogous to M-mode echocardiograms). Three-dimensional dynamic volume renderings of palate motion were displayed interactively (Vortex; CieMed, Singapore). A method suitable for the collection and visualization of four-dimensional information regarding monosyllabic speech using gated MRI was developed. These techniques were applied to a population of adult volunteer subjects with no history of speech problems and two patients with a history of cleft lip and palate. The techniques allowed good real-time visualization of velopharyngeal anatomy during its entire range of motion and was also able to image pathology-specific anatomic differences in the subjects with cleft lip and cleft palate. These methods may be applicable to a wide spectrum of problems in speech physiology research and for clinical decision-making regarding surgery for speech and outcomes analysis.