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Purpose: The study of air pressure in the vocal tract is essential to understanding vocal function. Changes in vocal tract shape during different phonatory gestures are hypothesized to produce nonuniform air pressure across lower vocal tract locations. Current methods of air pressure measurement, however, are limited to a single location in the anterior oral cavity. The purposes of this study were: (1) to assess the feasibility of a novel method of simultaneously measuring phonatory air pressure at multiple locations across the lower vocal tract using high-resolution pharyngeal manometry (HRM); and (2) to compare pressure across locations and among phonatory tasks. Method: Two subjects underwent HRM while performing phonatory tasks. A catheter was passed transnasally and air pressure was measured simultaneously at five locations between the velopharyngeal port and the upper esophageal sphincter. Descriptive statistics were calculated for each location by task, and for each task averaged across locations. Results: HRM was well tolerated, and air pressures from multiple locations in the lower vocal tract were able to be obtained simultaneously. During vocal tract semi-occlusion tasks, air pressures differed by location. Pressures averaged across locations demonstrated a pattern of increasing pressure with increasing semi-occlusion. Conclusions: HRM is feasible for measuring air pressure simultaneously at multiple locations in the lower vocal tract during phonation with high spatial and temporal resolution, providing rich data to augment understanding of vocal function. The high spatial and temporal resolution yielded by this new method, paired with preliminary evidence that pressures change by location as a function of phonatory task, may be useful in future assays exploring differences in lower vocal tract air pressures between normal and disordered populations.

Purpose: The study of air pressure in the vocal tract is essential to understanding vocal function. Changes in vocal tract shape during different phonatory gestures are hypothesized to produce nonuniform air pressure across lower vocal tract locations. Current methods of air pressure measurement, however, are limited to a single location in the anterior oral cavity. The purposes of this study were (a) to assess the feasibility of a novel method of simultaneously measuring phonatory air pressure at multiple locations across the lower vocal tract using high-resolution pharyngeal manometry (HRM) and (b) to compare pressure across locations and among phonatory tasks. Method: Two subjects underwent HRM while performing phonatory tasks. A catheter was passed transnasally and air pressure was measured simultaneously at five locations between the velopharyngeal port and the upper esophageal sphincter. Descriptive statistics were calculated for each location by task, and for each task averaged across locations. Results: HRM was well tolerated, and air pressures from multiple locations in the lower vocal tract were able to be obtained simultaneously. During vocal tract semi-occlusion tasks, air pressures differed by location. Pressures averaged across locations demonstrated a pattern of increasing pressure with increasing semi-occlusion. Conclusions: HRM is feasible for measuring air pressure simultaneously at multiple locations in the lower vocal tract during phonation with high spatial and temporal resolution, providing rich data to augment understanding of vocal function. The high spatial and temporal resolution yielded by this new method, paired with preliminary evidence that pressures change by location as a function of phonatory task, may be useful in future assays exploring differences in lower vocal tract air pressures between normal and disordered populations., The study of air pressure in the vocal tract is central to the study of vocal function. Vocal tract air pressure is associated with phonation efficiency, and changes to air [...]

The upper esophageal sphincter (UES) is the high-pressure zone marking the transition between the hypopharynx and esophagus. There is limited research surrounding the resting UES using pharyngeal high-resolution manometry (HRM) and existing normative data varies widely. This study describes the manometric representation of the resting UES using a clinically accessible method of measurement. Data were obtained from 87 subjects in a normative database of pharyngeal HRM with simultaneous videofluoroscopy. The resting UES manometric region was identified and ten measurement segments of this region were taken throughout the duration of the study using the Smart Mouse function within the manometry software. Intraclass correlation coefficients (ICC) were used to analyze within-subject reliability across measurements. Linear mixed-effects regression models were used to analyze how subject characteristics and manometric conditions influence resting UES pressure. There was excellent within-subject reliability between resting UES mean pressures (ICC = 0.96). In bivariate analysis, there were significant effects of age, number of sensors contained within the resting UES, and preceding swallow volume on mean resting UES pressure. For every 1 unit increase in age, there was a 0.19 unit decrease in resting UES pressure (p = 0.008). For every 1 unit increase in number of sensors contained within the resting UES, there was a 3.71 unit increase in resting UES pressure (p < 0.001). This study presents normative data for the resting UES, using a comprehensive and clinically accessible protocol that can provide standard comparison for the study of populations with swallowing disorders, particularly UES dysfunction, and provides support for UES-directed interventions. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this investigation was to evaluate the relationship between tongue-to-palate pressure and the electromyography (EMG) measured from the mylohyoid, anterior belly of the digastric, geniohyoid, medial pterygoid, velum, genioglossus, and intrinsic tongue muscles. Methods: Seven healthy adults performed tongue-to-palate pressure tasks at known percentages of their maximum pressure while intramuscular EMG was recorded from the muscles stated above. Multiple regression analysis was performed. Results: Predictors of pressure included the posterior fibers of the genioglossus, mylohyoid, anterior belly of digastric, medial pterygoid, and intrinsic tongue. Conclusions: Increasing tongue-to-palate pressure coincides with increased muscle activity. Activation of the floor-of-mouth, tongue, and jaw closing muscles increased tongue-to-palate pressure. These findings support the use of a tongue-press exercise to strengthen floor-of-mouth muscles, tongue, and jaw-closing muscles.

Purpose: The purpose of this study was to investigate inter- and intrarater reliability among expert users, novice users, and speech-language pathologists with a semiautomated high-resolution manometry analysis program. We hypothesized that all users would have high intrarater reliability and high interrater reliability. Method: Three expert users, 15 novice users, and 5 speech-language pathologists participated in this study. Following a 20-min training session, users analyzed 30 high-resolution manometry plots using an automated analysis program. Output parameters included 2- and 3-dimensional pressure integrals over 5 anatomical regions of interest. Intraclass correlations were used to examine inter- and intrarater reliability. An analysis of variance was also performed to determine any differences in mean output parameter values. Results: Within-group interrater reliability ranged from 0.54 to 0.99, and intergroup reliability ranged from 0.92 to 0.99. Intrarater reliability ranged from 0.67 to 1.00 across all groups. There were no significant differences of output parameters among groups. Conclusions: The high reliability observed after a short training session demonstrates that individuals with little to no prior knowledge of swallowing physiology can perform at a similar level as those with expertise. Given the quickness and ease of training in the use of this program, it has the potential for research and clinical utility. Key Words: high-resolution manometry, reproducibility of results, speech-language pathologist, swallowing, dysphagia, The introduction of high-resolution manometry (HRM) to evaluate pharyngeal swallowing has provided dysphagia researchers and clinicians with unique physiological information not otherwise obtainable by other clinically accepted methods such as [...]

Purpose: To model tension asymmetry caused by superior laryngeal nerve paralysis (SLNP) in excised larynges and apply perturbation, nonlinear dynamic, and aerodynamic analyses. Method: SLNP was modeled in 8 excised larynges using sutures and weights to mimic cricothyroid (CT) muscle function. Weights were removed from one side to create tension asymmetry, mimicking unilateral SLNP. Two sets of weights were used, 1 light and 1 heavy. Five conditions were evaluated: (a) no tension, (b) symmetrical light tension, (c) asymmetrical light tension, (d) symmetrical heavy tension, and (e) asymmetrical heavy tension. Results: Perturbation parameters were not significantly different across conditions: percent jitter, [chi square](4) = 3.70, p = .451; percent shimmer, F(4) = 0.95, p = .321. In addition, many measurements were invalid (error values >10). Second-order entropy was significantly different across conditions, F(4) = 5.432, p = .002, whereas correlation dimension was not, F(4) = 0.99, p = .428. Validity of these nonlineardynamic parameters was demonstrated by low standard deviations. Phonation threshold pressure, [chi square] (4) = 22.50, p < .001, and power, [chi square] (4) = 9.50, p = .05, differed significantly across conditions, whereas phonation threshold flow did not, [chi square] (4) = 4.08, p = .396. Conclusions: Nonlinear dynamic analysis differentiated between symmetrical and asymmetrical tension conditions, whereas traditional perturbation analysis was less useful in characterizing type 2 or 3 vocal signals. Supplementing acoustic with aerodynamic parameters may help distinguish among laryngeal disorders of neuromuscular origin. Key Words: superior laryngeal nerve paralysis, tension asymmetry, nonlinear dynamic analysis, acoustic analysis, aerodynamic analysis, Paralysis of the superior laryngeal nerve (SLN) impairs voice production by decreasing stimulation to the cricothyroid (CT) muscle, thereby preventing normal vocal fold elongation. Superior laryngeal nerve paralysis (SLNP) often [...]

Purpose: The authors present 3 methods of performing pattern recognition on spatiotemporal plots produced by pharyngeal high-resolution manometry (HRM). Method: Classification models, including the artificial neural networks (ANNs) multilayer perceptron (MLP) and learning vector quantization (LVQ), as well as support vector machines (SVM), were evaluated for their ability to identify disordered swallowing. Data were collected from 12 control subjects and 13 subjects with swallowing disorders; for this experiment, these subjects swallowed 5-ml water boluses. Following extraction of relevant parameters, a subset of the data was used to train the models, and the remaining swallows were then independently classified by the networks. Results: All methods produced high average classification accuracies, with MLP, SVM, and LVQ achieving accuracies of 96.44%, 91.03%, and 85.39%, respectively. When evaluating the individual contributions of each parameter and groups of parameters to the classification accuracy, parameters pertaining to the upper esophageal sphincter were most valuable. Conclusion: Classification models show high accuracy in segregating HRM data sets and represent 1 method of facilitating application of HRM to the clinical setting by eliminating the time required for some aspects of data extraction and interpretation. Key Words: artificial neural network, classification model, pharyngeal manometry, high-resolution manometry, deglutition, dysphagia, The pharyngeal swallow is a complex physiological event that requires muscle contraction and consequent pressure generation to move a bolus from the mouth to the esophagus (Cook, 1991; Kim, McCulloch, [...]

Purpose: The purpose of this investigation was to evaluate the relationship between tongue-to-palate pressure and the electromyography (EMG) measured from the mylohyoid, anterior belly of the digastric, geniohyoid, medial pterygoid, [...]