Instrumental assessment of velopharyngeal function and resonance: a review

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.

Automatic Detection System for Velopharyngeal Insufficiency Based on Acoustic Signals from Nasal and Oral Channels

Velopharyngeal insufficiency (VPI) is a type of pharyngeal function dysfunction that causes speech impairment and swallowing disorder. Speech therapists play a key role on the diagnosis and treatment of speech disorders. However, there is a worldwide shortage of experienced speech therapists. Artificial intelligence-based computer-aided diagnosing technology could be a solution for this. This paper proposes an automatic system for VPI detection at the subject level. It is a non-invasive and convenient approach for VPI diagnosis. Based on the principle of impaired articulation of VPI patients, nasal- and oral-channel acoustic signals are collected as raw data. The system integrates the symptom discriminant results at the phoneme level. For consonants, relative prominent frequency description and relative frequency distribution features are proposed to discriminate nasal air emission caused by VPI. For hypernasality-sensitive vowels, a cross-attention residual Siamese network (CARS-Net) is proposed to perform automatic VPI/non-VPI classification at the phoneme level. CARS-Net embeds a cross-attention module between the two branches to improve the VPI/non-VPI classification model for vowels. We validate the proposed system on a self-built dataset, and the accuracy reaches 98.52%. This provides possibilities for implementing automatic VPI diagnosis.

A segmentation-informed deep learning framework to register dynamic two-dimensional magnetic resonance images of the vocal tract during speech

Objective

Dynamic magnetic resonance (MR) imaging enables visualisation of articulators during speech. There is growing interest in quantifying articulator motion in two-dimensional MR images of the vocal tract, to better understand speech production and potentially inform patient management decisions. Image registration is an established way to achieve this quantification. Recently, segmentation-informed deformable registration frameworks have been developed and have achieved state-of-the-art accuracy. This work aims to adapt such a framework and optimise it for estimating displacement fields between dynamic two-dimensional MR images of the vocal tract during speech.

Methods

A deep-learning-based registration framework was developed and compared with current state-of-the-art registration methods and frameworks (two traditional methods and three deep-learning-based frameworks, two of which are segmentation informed). The accuracy of the methods and frameworks was evaluated using the Dice coefficient (DSC), average surface distance (ASD) and a metric based on velopharyngeal closure. The metric evaluated if the fields captured a clinically relevant and quantifiable aspect of articulator motion.

Results

The segmentation-informed frameworks achieved higher DSCs and lower ASDs and captured more velopharyngeal closures than the traditional methods and the framework that was not segmentation informed. All segmentation-informed frameworks achieved similar DSCs and ASDs. However, the proposed framework captured the most velopharyngeal closures.

Conclusions

A framework was successfully developed and found to more accurately estimate articulator motion than five current state-of-the-art methods and frameworks.

Significance

The first deep-learning-based framework specifically for registering dynamic two-dimensional MR images of the vocal tract during speech has been developed and evaluated.

Normative nasalance scores in Chilean adults

PURPOSE

The present study is aimed towards determining and comparing normative nasalance scores in Chilean Spanish-speaking adult men and women.

METHODS

40 women (age range 18 to 35, X = 25.79, SD = 5.83) and 36 men (age range 18 to 35, X = 26.45, SD = 4.08) were invited to participate, all of them without any previous speech therapy, neurological pathologies, intellectual deficits, hearing loss, syndromes, or other diagnosed pathologies that could impact speech production.A study of proper velopharyngeal function was performed, using a perceptual resonance evaluation. Nasalance was determined using a model 6450 Nasometer, during the reading of three standardized speech samples in Spanish: a nasal passage (NP), an oronasal passage (ONP), and an oral passage (OP). Also, the nasalance distance was calculated. Genders were compared using Wilcoxon tests for independent samples.

RESULTS

The NP presented the highest percentage of nasalance, with 52.13% (± 4.73), followed by the ONP with 25.38% (± 3.7), and finally the OP, which presented the lowest value of 14.15% (± 5.03). Meanwhile, nasalance distance was 37.98% (± 5.32). Finally, no significant differences were observed when comparing the nasalance between genders (p >0.05).

CONCLUSION

The nasalance values obtained were similar to those observed for other Spanish speakers. Also, male and women showed similar scores. The results of this study are a contribution to the indirect assessment of velopharyngeal function in Chilean adults.

Evaluation of noise excitation as a method for detection of hypernasality

Hypernasality is a disorder where excess nasal resonance is perceived during speech, often as a result of abnormal coupling between the oral and nasal tracts known as velopharyngeal insufficiency (VPI). The most common cause of VPI is a cleft palate, which affects around 1 in 1650 babies, around ⅓ of whom have persistent speech problems after surgery. Current equipment-based assessment methods are invasive and require expert knowledge, and perceptual assessment methods are limited by the availability of expert listeners and differing interpretations of assessment scales. Spectral analysis of hypernasality within the academic community has resulted in potentially useful spectral indicators, but these are highly variable, vowel specific, and not commonly used within clinical practice. Previous works by others have developed noise excitation technologies for the measurement of oral tract transfer functions using resonance measurement devices (RMD). These techniques provide an opportunity to investigate the structural system abnormalities which lead to hypernasality, without the need for invasive measurement equipment. Thus, the work presented in this study adapts these techniques for the detection of hypernasality. These adaptations include augmentation of the hardware and development of the software, so as to be suitable for transfer function measurement at the nostrils rather than the mouth (nRMD). The new method was tested with a single participant trained in hypernasal production, producing 'normal' and hypernasal vowels, and the recordings validated through a listening test by an expert listener and calculation of nasalance values using a nasality microphone. These validation stages indicated the reliability of the captured data, and analysis of the nRMD measurements indicated the presence of a systematic difference in the frequency range 2 to 2.5 kHz between normal and hypernasal speech. Further investigation is warranted to determine the generalisability of these findings across speakers, and to investigate the origins of differences manifesting in the transfer functions between conditions. This will provide new insights into the effects of nasal tract coupling on voice acoustics, which could in turn lead to the development of useful new tools to support clinicians in their work with hypernasality.

Secretion Bubbling as the Sound Mechanism for Nasal Rustle: A Perceptual Study

PURPOSE

Secretion bubbling on the superior aspect of the velopharyngeal (VP) valve typically occurs with a small VP opening during production of oral pressure consonants. The use of high-speed nasopharyngoscopy has shown correlation between the bubbling frequency and the acoustics captured with the nasal microphone of the nasometer. The purpose of this study was to investigate if the sound generated by the bubbling process is perceived as nasal rustle (also known as nasal turbulence).

METHOD

Speech samples were extracted from the data of patients who were diagnosed with nasal rustle (five boys and five girls, ranging in age from 5 to 10 years old). A customized filter was used to remove the sound generated by the secretion bubbling. Six experienced listeners were asked to rate the perception of nasal rustle in each speech stimuli before and after the filtering process.

RESULTS

Rating values for the perception of nasal rustle were overall reduced in all cases after the filtering process. Furthermore, the perception of nasal rustle was eliminated in 40% of the cases. Rating reliability was excellent before the filtering process and moderate to good after filtering.

CONCLUSION

Reducing the perception of nasal rustle using spectral filtering based on the bubbling frequencies supports the hypothesis that undesired sound in the nasal cavity is generated from the interaction of the turbulent airflow with the secretion bubbling.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.19111544.

Objective and subjective evaluation of Velopharyngeal Dysfunction (VPD) following surgical repair of the cleft palate using the furlow palatoplasty - A new tool

Velopharyngeal dysfunction (VPD) diagnosis and speech surgery outcomes are currently based solely on subjective evaluation criteria consisting of perceptual speech assessment and functional imaging. This study describes an objective and comparable method in VPD assessment and investigates the concurrence between the objective and subjective evaluations. The present study included 20 paediatric patients presenting with VPD after primary repair (intravelar veloplasty) of cleft palate. Our protocol was based on computerized analysis of voice parameters by means of an objective tool, spectrography integrated with Multi-Dimensional Voice Program (MDVP). The protocol also included perceptual evaluation by speech therapist and phoniatrician (consensus listening), and parents. This is a single surgeon, single centre experience and all patients underwent a secondary Furlow's palatoplasty. Assessments were performed pre- and postoperatively and upon completion of speech therapy. Results were compared using the two-tailed t student test for paired data. Statistical significance was set for p-values <0.05. Data analysis confirmed an improvement in velopharyngeal closure after surgery and speech therapy consistently with the results of perceptual evaluations. The results of the study confirmed the availability and reliability of an objective method for VPD evaluation based on the analysis of voice parameters with investigations that are simple and easily available in a hospital setting.

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.

A Deep Learning Algorithm for Objective Assessment of Hypernasality in Children With Cleft Palate

OBJECTIVES

Evaluation of hypernasality requires extensive perceptual training by clinicians and extending this training on a large scale internationally is untenable; this compounds the health disparities that already exist among children with cleft. In this work, we present the objective hypernasality measure (OHM), a speech-based algorithm that automatically measures hypernasality in speech, and validate it relative to a group of trained clinicians.

METHODS

We trained a deep neural network (DNN) on approximately 100 hours of a publicly-available healthy speech corpus to detect the presence of nasal acoustic cues generated through the production of nasal consonants and nasalized phonemes in speech. Importantly, this model does not require any clinical data for training. The posterior probabilities of the deep learning model were aggregated at the sentence and speaker-levels to compute the OHM.

RESULTS

The results showed that the OHM was significantly correlated with perceptual hypernasality ratings from the Americleft database (r = 0.797, p < 0.001) and the New Mexico Cleft Palate Center (NMCPC) database (r = 0.713, p < 0.001). In addition, we evaluated the relationship between the OHM and articulation errors; the sensitivity of the OHM in detecting the presence of very mild hypernasality; and established the internal reliability of the metric. Further, the performance of the OHM was compared with a DNN regression algorithm directly trained on the hypernasal speech samples.

SIGNIFICANCE

The results indicate that the OHM is able to measure the severity of hypernasality on par with Americleft-trained clinicians on thisdataset.

Robust Estimation of Hypernasality in Dysarthria with Acoustic Model Likelihood Features

Hypernasality is a common characteristic symptom across many motor-speech disorders. For voiced sounds, hypernasality introduces an additional resonance in the lower frequencies and, for unvoiced sounds, there is reduced articulatory precision due to air escaping through the nasal cavity. However, the acoustic manifestation of these symptoms is highly variable, making hypernasality estimation very challenging, both for human specialists and automated systems. Previous work in this area relies on either engineered features based on statistical signal processing or machine learning models trained on clinical ratings. Engineered features often fail to capture the complex acoustic patterns associated with hypernasality, whereas metrics based on machine learning are prone to overfitting to the small disease-specific speech datasets on which they are trained. Here we propose a new set of acoustic features that capture these complementary dimensions. The features are based on two acoustic models trained on a large corpus of healthy speech. The first acoustic model aims to measure nasal resonance from voiced sounds, whereas the second acoustic model aims to measure articulatory imprecision from unvoiced sounds. To demonstrate that the features derived from these acoustic models are specific to hypernasal speech, we evaluate them across different dysarthria corpora. Our results show that the features generalize even when training on hypernasal speech from one disease and evaluating on hypernasal speech from another disease (e.g., training on Parkinson's disease, evaluation on Huntington's disease), and when training on neurologically disordered speech but evaluating on cleft palate speech.

A cleft care workshop for speech and language pathologists in resource-limited countries: The participants' experiences about cleft care in Uganda and satisfaction with the training effect

OBJECTIVES

workshops and specialized training programs are often inaccessible for speech and language pathologists (SLPs) based in resource-limited countries given the lack of supply, the long travel distances and the excessive participation fees. To stimulate life-long learning opportunities for all, this study described and measured the effect of a free, two-day cleft care workshop for SLPs in Uganda. The workshop included different topics related to the assessment and treatment of children with a cleft of the palate with or without a cleft of the lip (CP ± L).

METHODS

The participants who presented during the two-day course were asked to complete a pre- and post-workshop questionnaire to evaluate their satisfaction. The pre-workshop form also included some questions concerning cleft care in Uganda. Both the pre- and post-workshop forms included three visual analogue scales to investigate the evolution of the participants' estimation of their knowledge regarding speech in patients with a CP ± L and to assess the changes in their self-confidence in the diagnosis and treatment of this population.

RESULTS

seventeen SLPs completed the pre- and post-workshop questionnaires. In general, the participants were highly satisfied with the different themes covered in the program. After the training course, the participants rated their general knowledge about CP ± L and their self-confidence in the diagnosis and treatment of children with a CP ± L significantly higher than before the workshop.

CONCLUSION

the vast majority of the SLPs reported that cleft care was not easily accessible in Uganda. The most commonly reported obstacle for cleft care was a lack of knowledge about this matter in the SLPs themselves highlighting the importance of the organization of additional education opportunities. The participants reported a significantly higher level of self-confidence in diagnosing and treating children with a CP ± L after the workshop. The content of this workshop can form the basis for future learning opportunities for SLPs based in resource-limited countries.

Detection and assessment of hypernasality in repaired cleft palate speech using vocal tract and residual features

The presence of hypernasality in repaired cleft palate (CP) speech is a consequence of velopharyngeal insufficiency. The coupling of the nasal tract with the oral tract adds nasal formant and antiformant pairs in the hypernasal speech spectrum. This addition deviates the spectral and linear prediction (LP) residual characteristics of hypernasal speech compared to normal speech. In this work, the vocal tract constriction feature, peak to side-lobe ratio feature, and spectral moment features augmented by low-order cepstral coefficients are used to capture the spectral and residual deviations for hypernasality detection. The first feature captures the lower-frequencies prominence in speech due to the presence of nasal formants, the second feature captures the undesirable signal components in the residual signal due to the nasal antiformants, and the third feature captures the information about formants and antiformants in the spectrum along with the spectral envelope. The combination of three features gives normal versus hypernasal speech detection accuracies of 87.76%, 91.13%, and 93.70% for /a/, /i/, and /u/ vowels, respectively, and hypernasality severity detection accuracies of 80.13% and 81.25% for /i/ and /u/ vowels, respectively. The speech data are collected from 30 control normal and 30 repaired CP children between the ages of 7 and 12.

Occult subtotal cleft of the secondary palate with VPI associated to 8q22.2 deletion

BACKGROUND

Submucous cleft palate is a cleft of the secondary palate with low phenotypic gene expression. It can occur as an isolated malformation or associated with a syndrome that includes certain facial features and other vocal tract malformations. Velopharyngeal insufficiency (VPI) is rare in cases of non - syndromic occult clefts of the secondary palate (OSCSP). In contrast, syndromic OCSP has a high prevalence of VPI. VPI requires surgical treatment in the vast majority of cases.

OBJECTIVE

To present a case of OSCSP with VPI after partial tonsillectomy and adenoidectomy (T & A) associated with facial features and other vocal tract malformations. A chromosomal abnormality (8q22.2 deletion) was demonstrated by cytogenetic testing.

CASE PRESENTATION

Eight year old female with VPI following partial T & A. OSCSP was diagnosed. Complete T & A was performed in preparation for a pharyngeal flap. Pharyngeal flap surgery was customized according to findings of videonasopharyngoscopy (VNP) and multiplanar videofluoroscopy (MPVF). VPI was corrected without intraoperative or postoperative complications.

CONCLUSION

The presence of multiple vocal tract malformations should be a red flag for suspecting a syndromic OSCSP. Surgical treatment of VPI in cases of OSCSP should be performed after complete T & A, Imaging procedures for assessing neck blood vessels and it should be customized according to imaging (VNP and MPVF) findings.

Objective assessment of cleft lip and palate speech intelligibility using articulation and hypernasality measures

Assessment of intelligibility is required to characterize the overall speech production capability and to measure the speech outcome of different interventions for individuals with cleft lip and palate (CLP). Researchers have found that articulation error and hypernasality have a significant effect on the degradation of CLP speech intelligibility. Motivated by this finding, the present work proposes an objective measure of sentence-level intelligibility by combining the information of articulation deficits and hypernasality. These two speech disorders represent different aspects of CLP speech. Hence, it is expected that the composite measure based on them may utilize complementary clinical information. The objective scores of articulation and hypernasality are used as features to train a regression model, and the output of the model is considered as the predicted intelligibility score. The Spearman's correlation coefficient based analysis shows a significant correlation between the predicted and perceptual intelligibility scores (ρ = 0.77, p < 0.001).

Comparison of three different surgical techniques for designing pharyngeal flaps according to findings of videonasopharyngoscopy and multiplanar videofluoroscopy

BACKGROUND

Velopharyngeal insufficiency (VPI) occurs when the velopharyngeal sphincter (VPS) is unable to completely seal anatomical closure between the nasal and oral cavities during speech. Palatal repair can restore VPS function but the prevalence of VPI after repair has been reported ranging from 20% to 40%. The combination of flexible videonasopharyngoscopy (FVNP) and multiplanar videofluoroscopy (MPVF) has been reported as the best approach for assessing the VPS mechanism and planning effective surgical procedures aimed to correct VPI.

OBJECTIVE

To study the outcome of three different techniques for performing pharyngeal flaps with the common denominator of individually designing the flap according to findings of VFNP and MPVF.

MATERIAL AND METHODS

A total of 140 cases of pharyngeal flap surgery were reviewed. Three surgeons performed 3 different surgical techniques. All cases underwent nasometry, VNP and MPVF preoperatively. All surgical procedures were carefully planned and designed according to findings of VNP and MPVF.

RESULTS

Nasal emission was completely eliminated in all cases. One-hundred-thirty-four patients (95%) demonstrated mean nasalance within normal limits after the surgical procedure whereas 6 patients persisted with mean nasalance scores above reference values postoperatively. There were no intraoperative or postoperative complications in any of the cases. No clinical data of sleep disordered breathing was detected in any of the cases after 2 months of postoperative follow-up. However, one case presented with clinical data of sleep disordered breathing 8 months postoperatively.

CONCLUSIONS

The results of this study suggest that as long as pharyngeal flaps are being designed according to the findings of imaging procedures, different surgical techniques can provide similar successful outcomes with minimal complications.

The relationship between health-related quality of life and speech in patients with cleft palate

INTRODUCTION

In health-care, current efforts focus on providing patient-centered care. Specifically for patients with velopharyngeal insufficiency, and by extent patients with cleft palate, the Velopharyngeal Insufficiency (VPI) Effects on Life Outcomes (VELO) questionnaire (Skirko et al., 2012; 2013) allows the clinician to map the impact of speech and swallowing difficulties on the patient's health-related quality of life (HRQoL). The current study evaluated the hypothesized association between this speech-related HRQoL measure and perceptually and instrumentally assessed speech variables, to provide evidence for the construct validity of the Dutch version of the VELO questionnaire.

MATERIALS AND METHODS

Thirty participants, twenty-five patients with cleft palate and five controls, were enrolled. Perceptual speech assessment was conducted following the recently developed Belgian Dutch outcome tool for perceptual speech assessment in patients with cleft palate. In addition, nasalance values and the Nasality Severity Index (NSI) 2.0 were determined. The relationship between these speech outcomes and the scores on the VELO parent report was determined using Spearman rank-order correlation coefficients.

RESULTS

Moderate to strong correlations were found between the total score on the VELO parent report and five speech variables: the VPC-SUM score (r_s = -0.476), speech understandability (r_s = -0.657), passive CSC's (r_s = -0.654), speech acceptability (r_s = -0.591) and the need for C(L)P-related speech therapy (r_s = -0.711). Furthermore, these variables were associated with at least one subscale of the VELO questionnaire.

DISCUSSION AND CONCLUSION

Correlations between speech outcomes and the Dutch version of the VELO questionnaire provide evidence for the construct validity of this version of the instrument. Furthermore, insights in these associations may lead the way to efficient therapy approaches, targeting speech features with the greatest impact on the patient's health-related quality of life.

OBJECTIVE MEASURES OF PLOSIVE NASALIZATION IN HYPERNASAL SPEECH

Hypernasal speech is a common symptom across several neurological disorders; however it has a variable acoustic signature, making it difficult to quantify acoustically or perceptually. In this paper, we propose the nasal cognate distinctiveness features as an objective proxy for hypernasal speech. Our method is motivated by the observation that incomplete velopharyngeal closure changes the acoustics of the resultant speech such that alveolar stops /t/ and /d/ map to the alveolar nasal /n/ and bilabial stops /b/ and /p/ map to bilabial nasal /m/. We propose a new family of features based on likelihood ratios between the plosives and their respective nasal cognates. These features are based on an acoustic model that is trained only on healthy speech, and evaluated on a set of 75 speakers diagnosed with different dysarthria subtypes and exhibiting varying levels of hypernasality. Our results show that the family of features compares favorably with the clinical perception of speech-language pathologists subjectively evaluating hypernasality.

Speech Phenotyping in Unaffected Family Members of Individuals With Nonsyndromic Cleft Lip With or Without Palate

OBJECTIVE

Subclinical phenotypes of nonsyndromic cleft lip with or without cleft palate (CL ± P) may be identified from clinically "unaffected" relatives and could be associated with specific cleft-related gene mutations. It has been hypothesized that velopharyngeal insufficiency (VPI) may be a subclinical phenotype of interest in this population, but this has not been explored quantitatively with appropriate control cohorts. The aim of this case-control study was to compare VPI in at-risk clinically unaffected relatives of individuals with nonsyndromic CL ± P with a low-risk matched normative Australian cohort.

PARTICIPANTS

Clinically unaffected (ie, with no overt cleft) first-degree relatives of a proband with nonsyndromic CL ± P (n = 189) and noncleft controls (n = 207).

MAIN OUTCOME MEASURE(S)

Perceptual measures of VPI encompassing resonance, nasal emission, and articulation were evaluated using the Great Ormond Street Speech Assessment. Quantitative measures of VPI were obtained from the Nasometer II using standardized adult and pediatric speech stimuli.

RESULTS

Both perceptual and instrumental measures showed no significant difference (P > .01) between the VPI in unaffected relatives and the noncleft comparison group. Mean nasalance scores for both groups were calculated and reported according to speech stimuli, age, and sex.

CONCLUSIONS

Results suggest that VPI, measured through speech, is not a significant subclinical phenotype of nonsyndromic CL ± P. Therefore, further familial genetic investigations exploring VPI may not yield meaningful results. Exploration across multiple subclinical phenotypes in larger cohorts may enable researchers to better understand the multifaceted nature of this complex and heterogeneous anomaly.

Acquired Velopharyngeal Dysfunction: Survey, Literature Review, and Clinical Recommendations

PURPOSE

The aim of this study was to describe the clinical assessment recommendations for acquired velopharyngeal dysfunction (AVPD) and, through a literature review and online survey, summarize current practice patterns for evaluation and treatment pathway determination for this target population.

METHOD

An online survey to query current assessment procedures and treatment pathway recommendations for AVPD was developed. Following survey results, a literature review was completed to determine evidence-based recommendations for assessment procedures and intervention recommendations based on assessment findings. Literature search terms included the following: acquired velopharyngeal dysfunction, hypernasality, non-cleft velopharyngeal dysfunction, velopharyngeal dysfunction, velopharyngeal dysfunction AND iatrogenic, velopharyngeal dysfunction AND neurogenic, velopharyngeal dysfunction AND assessment OR evaluation, velopharyngeal dysfunction AND treatment OR intervention, velopharyngeal dysfunction AND practice patterns OR clinical guidelines, velopharyngeal insufficiency. Inclusion criteria were limited to practice patterns/recommendations for assessment and/or treatment recommendations for AVPD, English language articles published between 2000 and 2017, and peer-reviewed journals. Studies regarding solely congenital or cleft palate velopharyngeal dysfunction and intervention outcome studies were excluded. Forty articles met inclusionary criteria.

RESULTS

The online survey results indicated lack of consensus for AVPD assessment and treatment recommendation protocols, with 93% of respondents indicating the need for a clinical guide for developing treatment recommendations. The majority of recommendations were filtered into an algorithm for clinical decision making.

CONCLUSIONS

Clinical uncertainty among speech-language pathologists surveyed and the paucity of published clinical guidelines for assessing individuals with AVPD indicate the need for additional clinical research for this disorder, one that is heterogeneous and distinct from those with congenital velopharyngeal dysfunction. The proposed evidence-based clinical worksheet may assist in determining management for patients with AVPD and may serve as a starting place for validation of a clinical guideline.

Intelligibility assessment of cleft lip and palate speech using Gaussian posteriograms based on joint spectro-temporal features

Intelligibility is considered as one of the primary measures for speech rehabilitation of individuals with a cleft lip and palate (CLP). Currently, speech processing and machine-learning-based objective methods are gaining more research interest as a way to quantify speech intelligibility. In this work, joint spectro-temporal features computed from a time-frequency representation of speech are explored to derive speech representations based on Gaussian posteriograms. A comparative framework using dynamic time warping (DTW) is used to quantify the intelligibility of child CLP speech. The DTW distance is used to score sentence-level intelligibility and tested for correlation with perceptual intelligibility ratings obtained from expert speech-language pathologists. A baseline DTW system using the conventional Mel-frequency cepstral coefficients (MFCCs) is also developed to compare the performance of the proposed system. Spearman's rank correlation coefficient between the objective intelligibility scores and the perceptual intelligibility rating is studied. A Williams significance test is conducted to assess the statistical significance of the correlation difference between the methods. The results show that the system based on joint spectro-temporal features significantly outperforms the MFCC-based system.

Long-term Average Spectra Analysis of Voice in Children With Cleft Palate

OBJECTIVES

The purpose of this study was to survey the spectral characteristics and to compare, using an acoustic analyzer, the objective data obtained from patients with cleft palates with the objective data of normal children using long-term average spectra (LTAS) analysis.

METHODS

Participants were divided into a clinical group and a control group. All participants were asked to practice reading a sentence to become fluent. The duration of each recording was about 60 seconds. All samples were subjected to acoustic analysis using Praat software. All recordings were analyzed acoustically using LTAS.

RESULTS

In this study, there was no significant difference between the control group and the clinical group in the low-frequency region (boys: 0-2720 Hz; girls: 0-2240 Hz). LTAS measurements showed a great difference between the control group and the clinical group in the middle-frequency region (boys: 2720-4000 Hz; girls: 2240-4000 Hz). We also found that the energy distributed in the clinical group was lower than that of the control group in the high-frequency region (4000 Hz-8000 Hz) in both boys and girls.

CONCLUSIONS

The results reveal a lack of flat region in the middle-frequency range in the clinical group (both boys and girls) in comparison with the control group. The results also reveal that there is no significant difference across the control group and the clinical group in the low-frequency region.

Perceptual Anchors and the Dispersion of Nasality Ratings

Objective

This investigation studied the effects of perceptual anchors on the dispersion and reliability of listener ratings of nasality.

Design

Listeners (N = 129) were assigned to one of six listening groups. Each group rated nasality independently for 100 speech samples on a seven-point scale that ranged from 1 = normal nasality to 7 = severe hypernasality. The anchors used were examples of a 1, 3, 4, 5, and/or 7 on the rating scale. These anchors were played selectively to group 2 (4), group 3 (1 and 7), group 4 (3 and 5), group 5 (1, 4, 7), and group 6 (7). Group 1 had no anchor.

Participants

Of the speakers, 95 were children followed by a craniofacial team and five were children without histories of speech disorders.

Main Outcome Measures

The outcome measures were 12,900 ratings of nasality on a seven-point scale.

Results

Q values showed that group 5, which was the only group to receive three anchors, had the lowest, or best, Q value (0.78), and group 1 (no anchor) had the highest, or worst, Q value (0.99). Across groups, the most reliable ratings were those at scale values 1 (Q = 0.46) and 7 (Q = 0.56). The least reliable ratings were at scale values 3 (Q = 1.01), 4 (Q = 1.03), and 5 (Q = 1.06).

Conclusions

Nasality rating reliability/dispersion was influenced by the presence and location of anchor stimuli. Consistent with absolute judgment theory, nasality ratings showed a strong end effect.

Quantitative Analysis of Velopharyngeal Movement by Applying Principal Component Analysis to Range Images Produced by a Three-Dimensional Endoscope

Objectives: The purpose of this study was to develop a new technique for analyzing velopharyngeal movement and to investigate its utility. Materials and Methods: Velopharyngeal motion of 20 normal individuals was analyzed. A three-dimensional (3D) endoscope was inserted into the oral cavity, and the movement of the soft palate was measured using an exclusive fixation device. Range images of the soft palate were produced during phonation of the Japanese vowel /a/, and virtual grids were then overlaid on these images. Principal component analyses were applied to the 3D coordinates of the intersections of the virtual grids. The centers of gravity of the virtual grids were calculated, and the magnitude of the shift of the grid intersections during phonation was calculated. Results: The first and the second principal component scores were responsible for the upper posterior direction and the upper direction, respectively. The average magnitude of the shift of the center of gravity was 4.75 mm in males and 4.33 mm in females. Conclusions: Quantitative analysis of velopharyngeal movement was achieved by a method of applying principal component analysis (PCA) to the range images obtained from a 3D endoscope. There was no sex difference in velopharyngeal movement.

Short-term and long-term test-retest reliability of the Nasality Severity Index 2.0

PURPOSE

The Nasality Severity Index 2.0 (NSI 2.0) forms a new, multiparametric approach in the assessment of hypernasality. To enable clinical implementation of this index, the short- and long-term test-retest reliability of this index was explored.

METHODS

In 40 normal-speaking adults (mean age 32y, SD 11, 18-56y) and 29 normal-speaking children (mean age 8y, SD 2, 4-12y), the acoustic parameters included in the NSI 2.0 (i.e. nasalance of the vowel /u/ and an oral text, and the voice low tone to high tone ratio (VLHR) of the vowel /i/) were obtained twice at the same test moment and during a second assessment two weeks later. After determination of the NSI 2.0, a comprehensive set of statistical measures was applied to determine its reliability.

RESULTS

Long-term variability of the NSI 2.0 and its parameters was slightly higher compared to the short-term variability, both in adults and in children. Overall, a difference of 2.82 for adults and 2.68 for children between the results of two consecutive measurements can be interpreted as a genuine change. With an ICC of 0.84 in adults and 0.77 in children, the NSI 2.0 additionally shows an excellent relative consistency. No statistically significant difference was withheld in the reliability of test-retest measurements between adults and children.

CONCLUSION

Reliable test-retest measurements of the NSI 2.0 can be performed. Consequently, the NSI 2.0 can be applied in clinical practice, in which successive NSI 2.0 scores can be reliably compared and interpreted.

LEARNING OUTCOMES

The reader will be able to describe and discuss both the short-term and long-term test-retest reliability of the Nasality Severity Index 2.0, a new multiparametric approach to hypernasality, and its parameters. Based on this information, the NSI 2.0 can be applied in clinical practice, in which successive NSI 2.0 scores, e.g. before and after surgery or speech therapy, can be compared and interpreted.

The relationship between the Nasality Severity Index 2.0 and perceptual judgments of hypernasality

PURPOSE

The Nasality Severity Index 2.0 (NSI 2.0) forms a new, multiparametric approach in the identification of hypernasality. The present study aimed to investigate the correlation between the NSI 2.0 scores and the perceptual assessment of hypernasality.

METHOD

Speech samples of 35 patients, representing a range of nasality from normal to severely hypernasal, were rated by four expert speech-language pathologists using visual analogue scaling (VAS) judging the degree of hypernasality, audible nasal airflow (ANA) and speech intelligibility. Inter- and intra-listener reliability was verified using intraclass correlation coefficients. Correlations between NSI 2.0 scores and its parameters (i.e. nasalance score of an oral text and vowel /u/, voice low tone to high tone ratio of the vowel /i/) and the degree of hypernasality were determined using Pearson correlation coefficients. Multiple linear regression analysis was used to investigate the possible influence of ANA and speech intelligibility on the NSI 2.0 scores.

RESULTS

Overall good to excellent inter- and intra-listener reliability was found for the perceptual ratings. A moderate, but significant negative correlation between NSI 2.0 scores and perceived hypernasality (r=-0.64) was found, in which a more negative NSI 2.0 score indicates the presence of more severe hypernasality. No significant influence of ANA or intelligibility on the NSI 2.0 was observed based on the regression analysis.

CONCLUSION

Because the NSI 2.0 correlates significantly with perceived hypernasality, it provides an easy-to-interpret severity score of hypernasality which will facilitate the evaluation of therapy outcomes, communication to the patient and other clinicians, and decisions for treatment planning, based on a multiparametric approach. However, research is still necessary to further explore the instrumental correlates of perceived hypernasality.

LEARNING OUTCOMES

The reader will be able to (1) describe and discuss current issues and influencing variables regarding perceptual ratings of hypernasality; (2) describe and discuss the relationship between the Nasality Severity Index 2.0, a new multiparametric approach to hypernasality, and perceptual judgments of hypernasality based on visual analogue scale ratings; (3) compare these results with the correlations based on a single parameter approach and (4) describe and discuss the possible influence of audible nasal airflow and speech intelligibility on the NSI 2.0 scores.