The Experts below are selected from a list of 312 Experts worldwide ranked by ideXlab platform
Liran Oren - One of the best experts on this subject based on the ideXlab platform.
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effects of velopharyngeal openings on flow characteristics of Nasal Emission
Biomechanics and Modeling in Mechanobiology, 2020Co-Authors: Elias Sundstrom, Suzanne Boyce, Liran OrenAbstract:Nasal Emission is a speech disorder where undesired airflow enters the Nasal cavity during speech due to inadequate closure of the velopharyngeal valve. Nasal Emission is typically inaudible with large velopharyngeal openings and very distorting with small openings. This study aims to understand how flow characteristics in the Nasal cavity change as a function of velopharyngeal opening using computational fluid dynamics. The model is based on a subject who was diagnosed with distorting Nasal Emission and a small velopharyngeal opening. The baseline geometry was delineated from CT scans that were taken, while the subject was sustaining a sibilant sound. Modifications to the model were done by systematically widening or narrowing the velopharyngeal opening while keeping the geometry constant elsewhere. Results show that if the flow resistance across the velopharyngeal valve is smaller than resistance across the oral constriction, flow characteristics such as velocity and turbulence are inversely proportional to the size of the opening. If flow resistance is higher across the velopharyngeal valve than the oral constriction, turbulence in the Nasal cavity will be reduced at a higher rate. These findings can be used to generalize that the area ratio of the velopharyngeal opening to the oral constriction is a factor that determines airflow characteristics and subsequently its sound during production of sibilant sound. It implies that the highest level of turbulence in the Nasal cavity, and subsequently the sound that will likely be perceived as the most severe Nasal Emission is produced when the size of openings is equal.
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Using High-Speed Nasopharyngoscopy to Quantify the Bubbling Above the Velopharyngeal Valve in Cases of Nasal Rustle.
The Cleft Palate-Craniofacial Journal, 2019Co-Authors: Liran Oren, Ann W Kummer, Michael Rollins, Srujana Padakanti, Ephraim Gutmark, Suzanne BoyceAbstract:Objective:The loud and severely distorting form of audible Nasal Emission (commonly known as Nasal turbulence or Nasal rustle) typically occurs with a small velopharyngeal opening during production...
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Sound production mechanisms of audible Nasal Emission during the sibilant /s/
Journal of the Acoustical Society of America, 2019Co-Authors: Elias Sundstrom, Liran OrenAbstract:Audible Nasal Emission is a speech disorder that involves undesired sound generated by airflow into the Nasal cavity during production of oral sounds. This disorder is associated with small-to-medium sized velopharyngeal openings. These openings induce turbulence in the Nasal cavity, which in turn produces sound. The purpose of this study is to examine the aeroacoustic mechanisms that generate turbulent sound during production of a sibilant /s/ with and without a small opening of the velopharyngeal valve. The models are based on two pediatric subjects who were diagnosed with severe audible Nasal Emission. The geometries were delineated from computed tomography scans taken while the subjects were sustaining a sibilant sound. Large eddy simulation with the Ffowcs Williams and Hawkings analogy was used to predict the flow behavior and its acoustic characterization. It shows that the majority of the acoustic energy is produced by surface loading, which is related to dipole sources that resonate in the Nasal cavity. The quadrupole source term that is associated with the unsteady shear layers is seen to be less significant. It also shows that closure of the velopharyngeal valve changes the far-field spectrum significantly because aeroacoustic mechanisms in the Nasal cavity are eliminated.Audible Nasal Emission is a speech disorder that involves undesired sound generated by airflow into the Nasal cavity during production of oral sounds. This disorder is associated with small-to-medium sized velopharyngeal openings. These openings induce turbulence in the Nasal cavity, which in turn produces sound. The purpose of this study is to examine the aeroacoustic mechanisms that generate turbulent sound during production of a sibilant /s/ with and without a small opening of the velopharyngeal valve. The models are based on two pediatric subjects who were diagnosed with severe audible Nasal Emission. The geometries were delineated from computed tomography scans taken while the subjects were sustaining a sibilant sound. Large eddy simulation with the Ffowcs Williams and Hawkings analogy was used to predict the flow behavior and its acoustic characterization. It shows that the majority of the acoustic energy is produced by surface loading, which is related to dipole sources that resonate in the Nasal c...
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sound production mechanisms of audible Nasal Emission during the sibilant s
Journal of the Acoustical Society of America, 2019Co-Authors: Elias Sundstrom, Liran OrenAbstract:Audible Nasal Emission is a speech disorder that involves undesired sound generated by airflow into the Nasal cavity during production of oral sounds. This disorder is associated with small-to-medium sized velopharyngeal openings. These openings induce turbulence in the Nasal cavity, which in turn produces sound. The purpose of this study is to examine the aeroacoustic mechanisms that generate turbulent sound during production of a sibilant /s/ with and without a small opening of the velopharyngeal valve. The models are based on two pediatric subjects who were diagnosed with severe audible Nasal Emission. The geometries were delineated from computed tomography scans taken while the subjects were sustaining a sibilant sound. Large eddy simulation with the Ffowcs Williams and Hawkings analogy was used to predict the flow behavior and its acoustic characterization. It shows that the majority of the acoustic energy is produced by surface loading, which is related to dipole sources that resonate in the Nasal cavity. The quadrupole source term that is associated with the unsteady shear layers is seen to be less significant. It also shows that closure of the velopharyngeal valve changes the far-field spectrum significantly because aeroacoustic mechanisms in the Nasal cavity are eliminated.
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understanding Nasal Emission during speech production a review of types terminology and causality
The Cleft Palate-Craniofacial Journal, 2019Co-Authors: Liran Oren, Ann W Kummer, Suzanne BoyceAbstract:There are several different types of Nasal Emission that can occur during speech due to either velopharyngeal dysfunction or abnormal articulation in the pharynx. Nasal Emission can be inaudible or...
Ann W Kummer - One of the best experts on this subject based on the ideXlab platform.
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Using High-Speed Nasopharyngoscopy to Quantify the Bubbling Above the Velopharyngeal Valve in Cases of Nasal Rustle.
The Cleft Palate-Craniofacial Journal, 2019Co-Authors: Liran Oren, Ann W Kummer, Michael Rollins, Srujana Padakanti, Ephraim Gutmark, Suzanne BoyceAbstract:Objective:The loud and severely distorting form of audible Nasal Emission (commonly known as Nasal turbulence or Nasal rustle) typically occurs with a small velopharyngeal opening during production...
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understanding Nasal Emission during speech production a review of types terminology and causality
The Cleft Palate-Craniofacial Journal, 2019Co-Authors: Liran Oren, Ann W Kummer, Suzanne BoyceAbstract:There are several different types of Nasal Emission that can occur during speech due to either velopharyngeal dysfunction or abnormal articulation in the pharynx. Nasal Emission can be inaudible or...
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Management of velopharyngeal insufficiency: The evolution of care and the current state of the art
Journal of Cleft Lip Palate and Craniofacial Anomalies, 2019Co-Authors: Ann W KummerAbstract:Velopharyngeal insufficiency (VPI) is a condition in which there is incomplete closure of the velopharyngeal valve during speech production. This results in hyperNasality and/or audible Nasal Emission. Nasal Emission can cause additional secondary characteristics, including weak or omitted consonants, compensatory articulation productions, short utterance length, and even dysphonia. Overall, this condition affects the quality and intelligibility of speech production, which can have a significant effect on the individual's communication and social interactions. This article provides a brief overview of how the management of VPI has evolved over the past 40 years (which is the extent of this author's career). In addition, the current state of the art in VPI management is discussed from this author's perspective. Finally, a pathway is suggested for the future evolution of care for patients affected by VPI.
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Nasal rustle: An evidence-based description
Journal of the Acoustical Society of America, 2017Co-Authors: Michael Rollins, Liran Oren, Ann W Kummer, J. P. Willging, Suzanne BoyceAbstract:“Nasal rustle” (also known as “Nasal turbulence”) is a loud Nasal distortion that can be heard during speech production in certain children with velopharyngeal insufficiency (VPI). It occurs when there is a leak of airflow into the Nasal cavity through a small velopharyngeal opening. While the perception of audible Nasal Emission—including Nasal rustle—is a standard means for the diagnosis of VPI, there is no consensus on the sound generation mechanism. Current hypotheses include aerodynamic turbulence, velar flutter, and bubbling of mucus secretion. This study investigates the correlation between the acoustic signal of Nasal rustle and physical movement at the superior velopharyngeal port. Several pediatric VPI patients were recorded via high-speed video nasopharyngoscopy and simultaneous nasometry during production of speech sounds susceptible to Nasal rustle. Instances of perceived Nasal rustle in the acoustic signal were identified and compared with the high-speed video. A high correlation was found b...
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Non-cleft causes of velopharyngeal dysfunction: Implications for treatment
International Journal of Pediatric Otorhinolaryngology, 2015Co-Authors: Ann W Kummer, Jennifer L. Marshall, Margaret M. WilsonAbstract:Abstract Although a history of cleft palate is the most common cause of velopharyngeal dysfunction (VPD), there are other disorders that can also cause hyperNasality and/or Nasal Emission. These include other structural anomalies of the velopharyngeal valve (velopharyngeal insufficiency), neurophysiological disorders that result in inadequate velopharyngeal movement (velopharyngeal incompetence), and even faulty articulation placement in the pharynx (velopharyngeal mislearning). Unfortunately, individuals with non-cleft causes of hyperNasality and/or Nasal Emission do not typically present at a cleft palate/craniofacial center where there are professionals who specialize in the evaluation and treatment of these disorders. As a result, they are often misdiagnosed and do not receive appropriate treatment. In this review, we present various conditions that can cause hyperNasality and/or Nasal Emission during speech. We discuss appropriate treatment based on the underlying cause of the condition. It is important that pediatric otolaryngologists are able to recognize these disorders so that affected patients are referred to specialists in velopharyngeal dysfunction for treatment.
Suzanne Boyce - One of the best experts on this subject based on the ideXlab platform.
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effects of velopharyngeal openings on flow characteristics of Nasal Emission
Biomechanics and Modeling in Mechanobiology, 2020Co-Authors: Elias Sundstrom, Suzanne Boyce, Liran OrenAbstract:Nasal Emission is a speech disorder where undesired airflow enters the Nasal cavity during speech due to inadequate closure of the velopharyngeal valve. Nasal Emission is typically inaudible with large velopharyngeal openings and very distorting with small openings. This study aims to understand how flow characteristics in the Nasal cavity change as a function of velopharyngeal opening using computational fluid dynamics. The model is based on a subject who was diagnosed with distorting Nasal Emission and a small velopharyngeal opening. The baseline geometry was delineated from CT scans that were taken, while the subject was sustaining a sibilant sound. Modifications to the model were done by systematically widening or narrowing the velopharyngeal opening while keeping the geometry constant elsewhere. Results show that if the flow resistance across the velopharyngeal valve is smaller than resistance across the oral constriction, flow characteristics such as velocity and turbulence are inversely proportional to the size of the opening. If flow resistance is higher across the velopharyngeal valve than the oral constriction, turbulence in the Nasal cavity will be reduced at a higher rate. These findings can be used to generalize that the area ratio of the velopharyngeal opening to the oral constriction is a factor that determines airflow characteristics and subsequently its sound during production of sibilant sound. It implies that the highest level of turbulence in the Nasal cavity, and subsequently the sound that will likely be perceived as the most severe Nasal Emission is produced when the size of openings is equal.
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Using High-Speed Nasopharyngoscopy to Quantify the Bubbling Above the Velopharyngeal Valve in Cases of Nasal Rustle.
The Cleft Palate-Craniofacial Journal, 2019Co-Authors: Liran Oren, Ann W Kummer, Michael Rollins, Srujana Padakanti, Ephraim Gutmark, Suzanne BoyceAbstract:Objective:The loud and severely distorting form of audible Nasal Emission (commonly known as Nasal turbulence or Nasal rustle) typically occurs with a small velopharyngeal opening during production...
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understanding Nasal Emission during speech production a review of types terminology and causality
The Cleft Palate-Craniofacial Journal, 2019Co-Authors: Liran Oren, Ann W Kummer, Suzanne BoyceAbstract:There are several different types of Nasal Emission that can occur during speech due to either velopharyngeal dysfunction or abnormal articulation in the pharynx. Nasal Emission can be inaudible or...
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Nasal rustle: An evidence-based description
Journal of the Acoustical Society of America, 2017Co-Authors: Michael Rollins, Liran Oren, Ann W Kummer, J. P. Willging, Suzanne BoyceAbstract:“Nasal rustle” (also known as “Nasal turbulence”) is a loud Nasal distortion that can be heard during speech production in certain children with velopharyngeal insufficiency (VPI). It occurs when there is a leak of airflow into the Nasal cavity through a small velopharyngeal opening. While the perception of audible Nasal Emission—including Nasal rustle—is a standard means for the diagnosis of VPI, there is no consensus on the sound generation mechanism. Current hypotheses include aerodynamic turbulence, velar flutter, and bubbling of mucus secretion. This study investigates the correlation between the acoustic signal of Nasal rustle and physical movement at the superior velopharyngeal port. Several pediatric VPI patients were recorded via high-speed video nasopharyngoscopy and simultaneous nasometry during production of speech sounds susceptible to Nasal rustle. Instances of perceived Nasal rustle in the acoustic signal were identified and compared with the high-speed video. A high correlation was found b...
Elias Sundstrom - One of the best experts on this subject based on the ideXlab platform.
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effects of velopharyngeal openings on flow characteristics of Nasal Emission
Biomechanics and Modeling in Mechanobiology, 2020Co-Authors: Elias Sundstrom, Suzanne Boyce, Liran OrenAbstract:Nasal Emission is a speech disorder where undesired airflow enters the Nasal cavity during speech due to inadequate closure of the velopharyngeal valve. Nasal Emission is typically inaudible with large velopharyngeal openings and very distorting with small openings. This study aims to understand how flow characteristics in the Nasal cavity change as a function of velopharyngeal opening using computational fluid dynamics. The model is based on a subject who was diagnosed with distorting Nasal Emission and a small velopharyngeal opening. The baseline geometry was delineated from CT scans that were taken, while the subject was sustaining a sibilant sound. Modifications to the model were done by systematically widening or narrowing the velopharyngeal opening while keeping the geometry constant elsewhere. Results show that if the flow resistance across the velopharyngeal valve is smaller than resistance across the oral constriction, flow characteristics such as velocity and turbulence are inversely proportional to the size of the opening. If flow resistance is higher across the velopharyngeal valve than the oral constriction, turbulence in the Nasal cavity will be reduced at a higher rate. These findings can be used to generalize that the area ratio of the velopharyngeal opening to the oral constriction is a factor that determines airflow characteristics and subsequently its sound during production of sibilant sound. It implies that the highest level of turbulence in the Nasal cavity, and subsequently the sound that will likely be perceived as the most severe Nasal Emission is produced when the size of openings is equal.
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Sound production mechanisms of audible Nasal Emission during the sibilant /s/
Journal of the Acoustical Society of America, 2019Co-Authors: Elias Sundstrom, Liran OrenAbstract:Audible Nasal Emission is a speech disorder that involves undesired sound generated by airflow into the Nasal cavity during production of oral sounds. This disorder is associated with small-to-medium sized velopharyngeal openings. These openings induce turbulence in the Nasal cavity, which in turn produces sound. The purpose of this study is to examine the aeroacoustic mechanisms that generate turbulent sound during production of a sibilant /s/ with and without a small opening of the velopharyngeal valve. The models are based on two pediatric subjects who were diagnosed with severe audible Nasal Emission. The geometries were delineated from computed tomography scans taken while the subjects were sustaining a sibilant sound. Large eddy simulation with the Ffowcs Williams and Hawkings analogy was used to predict the flow behavior and its acoustic characterization. It shows that the majority of the acoustic energy is produced by surface loading, which is related to dipole sources that resonate in the Nasal cavity. The quadrupole source term that is associated with the unsteady shear layers is seen to be less significant. It also shows that closure of the velopharyngeal valve changes the far-field spectrum significantly because aeroacoustic mechanisms in the Nasal cavity are eliminated.Audible Nasal Emission is a speech disorder that involves undesired sound generated by airflow into the Nasal cavity during production of oral sounds. This disorder is associated with small-to-medium sized velopharyngeal openings. These openings induce turbulence in the Nasal cavity, which in turn produces sound. The purpose of this study is to examine the aeroacoustic mechanisms that generate turbulent sound during production of a sibilant /s/ with and without a small opening of the velopharyngeal valve. The models are based on two pediatric subjects who were diagnosed with severe audible Nasal Emission. The geometries were delineated from computed tomography scans taken while the subjects were sustaining a sibilant sound. Large eddy simulation with the Ffowcs Williams and Hawkings analogy was used to predict the flow behavior and its acoustic characterization. It shows that the majority of the acoustic energy is produced by surface loading, which is related to dipole sources that resonate in the Nasal c...
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sound production mechanisms of audible Nasal Emission during the sibilant s
Journal of the Acoustical Society of America, 2019Co-Authors: Elias Sundstrom, Liran OrenAbstract:Audible Nasal Emission is a speech disorder that involves undesired sound generated by airflow into the Nasal cavity during production of oral sounds. This disorder is associated with small-to-medium sized velopharyngeal openings. These openings induce turbulence in the Nasal cavity, which in turn produces sound. The purpose of this study is to examine the aeroacoustic mechanisms that generate turbulent sound during production of a sibilant /s/ with and without a small opening of the velopharyngeal valve. The models are based on two pediatric subjects who were diagnosed with severe audible Nasal Emission. The geometries were delineated from computed tomography scans taken while the subjects were sustaining a sibilant sound. Large eddy simulation with the Ffowcs Williams and Hawkings analogy was used to predict the flow behavior and its acoustic characterization. It shows that the majority of the acoustic energy is produced by surface loading, which is related to dipole sources that resonate in the Nasal cavity. The quadrupole source term that is associated with the unsteady shear layers is seen to be less significant. It also shows that closure of the velopharyngeal valve changes the far-field spectrum significantly because aeroacoustic mechanisms in the Nasal cavity are eliminated.
Dennis M Ruscello - One of the best experts on this subject based on the ideXlab platform.
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Treatment of Velopharyngeal Closure for Speech: Discussion and Implications for Management
2007Co-Authors: Dennis M RuscelloAbstract:Abstract The velopharyngeal closure mechanism acts as a valve to separate the oral and Nasal cavities during speech and swallowing. Velopharyngeal closure deficits are generally identified by the speech-language pathologist and corrected through surgery or speech prosthetics. However, there is a small subset of clients who may benefit from treatments using task specific muscle rehabilitation procedures. This review article addresses the following topics: structure/function relationships of velopharyngeal closure, motor programming of velopharyngeal closure, aims and findings of various types of muscle treatment programs, discussion and rationale of successful muscle treatments, and guidelines for utilizing muscle treatment for the management of clients with velopharyngeal closure deficits. Keywords: Velopharyngeal closure, muscle treatment, Nasal Emission, hyperNasality. Introduction Velopharyngeal closure is the neurophysiologic act of partitioning the oral cavity from the Nasal cavity during speech and nonspeech activities. Thompson and Hixon (1979) characterize the velopharyngeal closure mechanism as a valve whose actions act to separate the oral and Nasal cavities. Moon and Kuehn (1996) describe the mechanism for speech as an articulator that must operate according to rules of neuromotor programming, and whose activity must be synchronized with the actions of other articulators to attain perceptually acceptable speech. McWilliams, Morris, and Shelton (1984, 1990) indicate that velopharyngeal closure for speech consists of velar movement and contact with the lateral and posterior pharyngeal walls. The velum moves in an upward and backward direction to articulate with the pharyngeal walls. Normal speakers exhibit differential patterns of muscle activity of the velum, lateral pharyngeal walls and posterior pharyngeal wall (Iglesias, Kuehn, & Morris, 1980; Shprintzen, Lencione, McCall & Skolnick, 1974; Zwitman, Sonderman, & Ward, 1974). That is, they achieve closure but the articulators contribute in different ways depending on the speaker. Velopharyngeal closure for speech allows a speaker to generate sufficient air pressure and flow for the production of pressure consonants and also permits the production of voiced sounds without hyperNasal resonance. Speakers who are unable to achieve velopharyngeal closure or who exhibit faulty timing of closure often demonstrate problems with speech production and such problems manifest in articulation and resonance disorders (Kuehn, 1979; Morris, 1992; Warren, Dalston, & Mayo, 1993). Articulation problems are normally found with the plosive, fricative and affricate sound categories, since they require the generation of high intraoral air pressure (McWilliams et al., 1990; Peterson-Falzone, Hardin-Jones,& Karnell, 2001; Shelton, Hahn, & Morris, 1968; Shelton, Morris, & McWilliams, 1973). These pressure sounds, may be produced with Nasal Emission, or the client may use compensatory substitutions in place of the pressure sounds. Audible Nasal Emission is the auditory perception or air passing through the nose during the production of a pressure sound. The speaker may produce the sound at the correct point of articulation, but Nasal Emission accompanies the production. Compensatory errors are sounds that are used in place of pressure sounds and generally produced at a more posterior point of articulation than the intended sound. For instance, one of the most frequent compensatory errors utilized by speakers with cleft palate is the glottal stop. It is produced by bringing the vocal folds together to create a complete constriction and then releasing the built-up air pressure created by the lungs. Resonance is the product of the transfer function of the laryngeal sound source (Peterson-Falzone et al., 2006). The vocal tract acts as a filter to selectively modify in different ways the complex laryngeal tone that is created by the vibration of the vocal folds. …
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Cooperative Service Delivery Between a University Clinic and a School System
Language Speech and Hearing Services in Schools, 1995Co-Authors: Dennis M Ruscello, Diane Yanero, Mohssen GhalichebafAbstract:A cooperative service delivery model was developed between a university clinic and a public school system to evaluate and treat a child with phoneme-specific Nasal Emission. The youngster was diagn...
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modification of context specific Nasal Emission
Journal of Speech Language and Hearing Research, 1991Co-Authors: Dennis M Ruscello, Linda I Shuster, Annette SandwischAbstract:An adult patient with context-specific Nasal Emission was enrolled in a treatment program that attempted to modify the problem through a combination of biofeedback and articulation training. Prior to, during, and at the termination of treatment, perceptual, acoustic, and physiologic measures were obtained. The data indicate that the articulatory pattern was modified and that such patterns are subject to change through speech treatment.
