Tongue Shape Dynamics in Swallowing Using Sagittal Ultrasound

Ultrasonographic analysis of the hyoid bone distance in individuals with neurogenic oropharyngeal dysphagia

To compare the ultrasound measurement of distance from the approximation of the hyoid bone during of the maximum deglutition peak between healthy individuals and neurogenic dysphagic individuals and to verify the effect of food consistencies on the displacement of the hyoid bone. Prospective, controlled clinical study. Ultrasound recordings of the oropharyngeal deglutition were conducted in 10 adults diagnosed with oropharyngeal dysphagia and in 10 healthy adults, matched by sex and age group. A portable ultrasound model Micro ultrasound system with a microconvex transducer 5-10 MHz, coupled to a computer as well as the head stabilizer were used. The ultrasound images were recorded using the AAA software (Articulate Assistant Advanced) at a rate of 120 frames/second. Food consistencies level 0 (free volume and 5 mL) and level 4 (5 mL) were used, based on the International Dysphagia Diet Standardisation Initiative (IDSSI). The calculation of the mean and standard deviation was used for the descriptive analysis, while the repeated measures ANOVA test was used for the inferential analysis. Results showed dysphagic individuals had lower elevation of the hyoid bone marked by a longer distance from the approximation of the hyoid bone during of the maximum deglutition peak when compared to healthy individuals, regardless of the food consistency offered. It was concluded that the ultrasound measurement of distance from the approximation of the hyoid bone during of the maximum deglutition peak showed less laryngeal elevation in individuals with neurogenic oropharyngeal dysphagia when compared to healthy individuals for all food consistencies offered.

Methodological Procedures to Acquire and Analyze Ultrasound Images of Swallowing: A Scoping Review

This scoping review aimed to identify methodological procedures for acquiring and analyzing ultrasound images related to swallowing in adults and older adults. The inclusion criteria were based on the PCC strategy (participants, concept, and context), as follows: population (adults and older adults), concept (ultrasound assessment), and context (swallowing assessment). The review included observational, experimental, descriptive, and analytical studies and excluded those that were not available in full, animal studies, in vitro studies, letters to the editor, errata, study protocols, and those that used ultrasound for purposes other than swallowing. There were no language and time restrictions. Two independent blinded professionals selected 81 articles that met the inclusion criteria from different databases. The most evaluated parameters included tongue morphology and movements, hyoid bone displacement, swallowing muscle area, and pharyngeal residue detection, such as pharyngeal wall mobility. They used convex and linear transducers (3 MHz to 8 MHz) positioned in the submental, laryngeal, and lateral regions of the neck. The subjects were seated and instructed to eat different food volumes and consistencies. The literature mapping showed that ultrasound is a promising diagnostic tool, helping clinicians understand swallowing disorders, as it provides static and dynamic images in different modes and positions. Also, patients receive real-time biofeedback of changes related to dysphagia.

Reliability of Measuring Geniohyoid Cross-Sectional Area with B-Mode Ultrasound

B-mode ultrasound is a safe noninvasive procedure that has been used to characterize aspects of the oropharyngeal swallow. The submental suprahyoid muscles are often investigated with ultrasound because of their contributions to hyolaryngeal elevation. There are several techniques for positioning the ultrasound transducer in the coronal plane, however, there is limited research on how reliability of measurement of the cross-sectional area (CSA) of the geniohyoid differs across transducer placement technique. This study examined three methods of transducer placement in the coronal plane by two examiners to determine the reliability of measurement of CSA of the geniohyoid muscle. Forty healthy adults participated in the study. Each participant's geniohyoid muscles were imaged using B-mode ultrasound under three transducer placement conditions in the coronal plane by two examiners. Geniohyoid CSA was measured from each ultrasound image. A three-way mixed-methods ANOVA was used to determine whether there were significant differences in geniohyoid CSA among transducer position conditions, trials, and examiners. There were significant differences among the transducer placement conditions, indicating that each condition was measuring a different portion of the muscle. There were no significant differences among repeated trials nor between examiners within each method of transducer placement. All three conditions of transducer placement were reliable at measuring geniohyoid CSA across trials and examiners. This study emphasizes the need for consistency of placement, whichever method is selected. It also highlights the need for researchers to provide a precise description of methods for positioning the transducer so that placement is reproducible.

Using Sequence Analyses to Quantitatively Measure Oropharyngeal Swallowing Temporality in Point-of-Care Ultrasound Examinations: A Pilot Study

(1) Background: Swallowing is a complex process that comprises well-timed control of oropharyngeal and laryngeal structures to achieve airway protection and swallowing efficiency. To understand its temporality, previous research adopted adherence measures and revealed obligatory pairs in healthy swallows and the effect of aging and bolus type on the variability of event timing and order. This study aimed to (i) propose a systemic conceptualization of swallowing physiology, (ii) apply sequence analyses, a set of information-theoretic and bioinformatic methods, to quantify and characterize swallowing temporality, and (iii) investigate the effect of aging and dysphagia on the quantified variables using sequence analyses measures. (2) Method: Forty-three participants (17 young adults, 15 older adults, and 11 dysphagic adults) underwent B-mode ultrasound swallowing examinations at the mid-sagittal plane of the submental region. The onset, maximum, and offset states of hyoid bone displacement, geniohyoid muscle contraction, and tongue base retraction were identified and sorted to form sequences which were analyzed using an inventory of sequence analytic techniques; namely, overlap coefficients, Shannon entropy, and longest common subsequence algorithms. (3) Results: The concurrency of movement sequence was found to be significantly impacted by aging and dysphagia. Swallowing sequence variability was also found to be reduced with age and the presence of dysphagia (H(2) = 52.253, p < 0.001, η2 = 0.260). Four obligatory sequences were identified, and high adherence was also indicated in two previously reported pairs. These results provided preliminary support for the validity of sequence analyses for quantifying swallowing sequence temporality. (4) Conclusions: A systemic conceptualization of human deglutition permits a multi-level quantitative analysis of swallowing physiology. Sequence analyses are a set of promising quantitative measurement techniques for point-of-care ultrasound (POCUS) swallowing examinations and outcome measures for swallowing rehabilitation and evaluation of associated physiological conditions, such as sarcopenia. Findings in the current study revealed physiological differences among healthy young, healthy older, and dysphagic adults. They also helped lay the groundwork for future AI-assisted dysphagia assessment and outcome measures using POCUSs. Arguably, the proposed conceptualization and analyses are also modality-independent measures that can potentially be generalized for other instrumental swallowing assessment modalities.

Exposure to Canadian French Cued Speech Improves Consonant Articulation in Children With Cochlear Implants: Acoustic and Articulatory Data

PURPOSE

One of the strategies that can be used to support speech communication in deaf children is cued speech, a visual code in which manual gestures are used as additional phonological information to supplement the acoustic and labial speech information. Cued speech has been shown to improve speech perception and phonological skills. This exploratory study aims to assess whether and how cued speech reading proficiency may also have a beneficial effect on the acoustic and articulatory correlates of consonant production in children.

METHOD

Eight children with cochlear implants (from 5 to 11 years of age) and with different receptive proficiency in Canadian French Cued Speech (three children with low receptive proficiency vs. five children with high receptive proficiency) are compared to 10 children with typical hearing (from 4 to 11 years of age) on their production of stop and fricative consonants. Articulation was assessed with ultrasound measurements.

RESULTS

The preliminary results reveal that cued speech proficiency seems to sustain the development of speech production in children with cochlear implants and to improve their articulatory gestures, particularly for the place contrast in stops as well as fricatives.

CONCLUSION

This work highlights the importance of studying objective data and comparing acoustic and articulatory measurements to better characterize speech production in children.

Bedside Ultrasound to Identify and Predict Severity of Dysphagia Following Ischemic Stroke: Human Versus Artificial Intelligence

OBJECTIVE

Dysphagia is a significant ischemic stroke complication that can lead to aspiration. Identification of at-risk patients can be logistically difficult and costly. Researchers investigated whether quantitative ultrasound assessment of hyoid bone movement during induced swallowing would predict failure of videofluoroscopy (VFS) or fiberoptic endoscopic evaluation of swallowing (FEES), as determined by a penetration-aspiration scale (PAS) score. Additionally, ability of a machine learning (ML) algorithm to predict PAS success or failure from real-time ultrasound video recordings was assessed.

METHODS

A prospective, single-blinded, observational pilot study was conducted from June 2019 through March 2020 at a comprehensive stroke center on a convenience sample of patients admitted with diagnosis of acute ischemic stroke undergoing VFS or FEES as part of dysphagia assessment. Researchers performed a midsagittal airway ultrasound during swallowing in patients receiving an objective swallowing assessment by speech language pathologists who were blinded to ultrasound results. Sonologists measured hyoid bone movement, and researchers then constructed an ML algorithm designed for real-time video analysis using a long short-term memory network with an embedded VGG16 convolutional neural network.

RESULTS

Videos from 69 patients were obtained with their respective PAS results. In total, 90% of available videos were used for algorithm training. After training, the ML algorithm was challenged with the 10% previously unseen videos and then compared with PAS outcomes. Statistical analysis included logistic regression and correlation matrix testing on human ultrasound measurements. Cohen's κ was calculated to compare deep learning algorithm prediction with PAS results. Measurement of hyoid bone elevation, forward displacement, total displacement and mandible length was unable to predict PAS assessment outcome (p values = 0.36, 0.13, 0.11 and 0.32, respectively). The ML algorithm showed substantial agreement with PAS testing results for predicting test outcome (κ = 0.79; 95% confidence interval: 0.52-1.0) CONCLUSION: Manual ultrasound measurement of hyoid movement during swallowing in stroke patients failed to predict PAS swallowing results. However, an ML algorithm showed substantial agreement with PAS results despite a small data set, which could greatly improve access to dysphagia assessment in the future.

Is it possible to reveal a typical swallowing pattern for specific skeletal malocclusion types using M-mode sonographic imaging of tongue movements?

PURPOSE

The present study aims to compare the M‑mode ultrasound findings of different skeletal malocclusions and to evaluate whether sonographic parameters can be used for the diagnosis of malocclusions.

METHODS

Tongue movements of 36 adolescents aged between 10.37 and 17.29 years (mean 14.25 ± 1.78 years) were assessed using simultaneous two-dimensional real-time B‑mode and M‑mode sonography. The swallowing patterns of the subjects were visualized recording the motion of the tongue surface in the ultrasound images utilizing a fixed scan line through the middle of the tongue. M‑mode scans of tongue motion during empty deglutition were recorded. The parameters range, duration, and speed were computed for the entirety of the swallowing process using M‑mode examination. Findings were evaluated and statistically analyzed.

RESULTS

No clear intraindividual repeatability in the M‑mode imaging of the subjects' swallowing process could be observed. Considering the setup used in the study, it was not always possible to distinguish individual swallowing stages in the M‑mode images with regard to the chosen reference points. The average duration, range of motion, and speed of swallowing were found to be 2.43 s, 24.06 mm, and 10.34 mm/s, respectively. The findings showed both intra- and intersubject variability during empty swallowing.

CONCLUSION

With the help of the metrics that could be calculated based on the M‑mode images, it was not possible to differentiate the swallowing acts of different skeletal malocclusion types. It remains unclear whether M‑mode imaging can accurately visualize the swallowing pattern. Therefore, further progress in technology and multidisciplinary work is needed in order to establish diagnostic references regarding swallowing.

Ultrasonography for Eating and Swallowing Assessment: A Narrative Review of Integrated Insights for Noninvasive Clinical Practice

Dysphagia is a syndrome of abnormal eating function resulting from a variety of causative diseases, and is associated with malnutrition. To date, the swallowing function has been difficult to examine without the use of invasive and expensive methods, such as the videofluorographic swallowing study or fiberoptic endoscopic evaluation of swallowing. In recent years, progress has been made in the clinical application of ultrasound equipment for the evaluation of body compositions near the body surface, including the assessment of nutritional status. Ultrasound examination is a noninvasive procedure and relatively inexpensive, and the equipment required is highly portable thanks to innovations such as wireless probes and tablet monitoring devices. The process of using ultrasound to visualize the geniohyoid muscle, digastric muscle, mylohyoid muscle, hyoid bone, tongue, masseter muscle, genioglossus muscle, orbicularis oris muscle, temporalis muscle, pharynx, esophagus, and larynx, and the methods used for evaluating these structures, are provided in this study in detail. This study also aims to propose a protocol for the assessment of swallowing-related muscles that can be applied in real-world clinical practice for the diagnosis of sarcopenic dysphagia, which can occur in elderly patients with sarcopenia, and has received much attention in recent years.

Overview of Ultrasound in Dentistry for Advancing Research Methodology and Patient Care Quality with Emphasis on Periodontal/Peri-implant Applications

BACKGROUND

Ultrasound is a non-invasive, cross-sectional imaging technique emerging in dentistry. It is an adjunct tool for diagnosing pathologies in the oral cavity that overcomes some limitations of current methodologies, including direct clinical examination, 2D radiographs, and cone beam computerized tomography. Increasing demand for soft tissue imaging has led to continuous improvements on transducer miniaturization and spatial resolution. The aims of this study are (1) to create a comprehensive overview of the current literature of ultrasonic imaging relating to dentistry, and (2) to provide a view onto investigations with immediate, intermediate, and long-term impact in periodontology and implantology.

METHODS

A rapid literature review was performed using two broad searches conducted in the PubMed database, yielding 576 and 757 citations, respectively. A rating was established within a citation software (EndNote) using a 5-star classification. The broad search with 757 citations allowed for high sensitivity whereas the subsequent rating added specificity.

RESULTS

A critical review of the clinical applications of ultrasound in dentistry was provided with a focus on applications in periodontology and implantology. The role of ultrasound as a developing dental diagnostic tool was reviewed. Specific uses such as soft and hard tissue imaging, longitudinal monitoring, as well as anatomic and physiological evaluation were discussed.

CONCLUSIONS

Future efforts should be directed towards the transition of ultrasonography from a research tool to a clinical tool. Moreover, a dedicated effort is needed to introduce ultrasonic imaging to dental education and the dental community to ultimately improve the quality of patient care.

Application of Ultrasonography in Neurogenic Dysphagia: A Systematic Review

Swallowing disorders are common in neurological diseases, with dysphagia representing one of the most prevalent complications that may cause poor quality of life, reduce independence, and increase mortality. Rapid identification of dysphagia is necessary to reduce the risk of penetration and aspiration, and to early start rehabilitation protocols. Among the methods that can be used to evaluate dysphagia and its components, ultrasound imaging has been suggested to support the evaluation of dysphagia by providing measures of both static and dynamic anatomical components. The aim of this systematic review is to evaluate the usefulness of ultrasonography in neurogenic dysphagia according to current literature. From 2000 to 2020, 633 studies with the appropriate search terms for ultrasound and dysphagia were identified. After screening them, 10 studies were included in the qualitative analysis. Patients with the following neurologic conditions were studied with ultrasonography for dysphagia: Parkinson's disease, muscle dystrophy, amyotrophic lateral sclerosis, and stroke. The main outcomes of ultrasonography were swallowing muscles thickness (e.g., tongue), and dynamic measures such as hyoid displacement. The different protocols used in the studies, as well as their outcomes, did not allow to provide standard procedures and normative or cut-off values in the presented diseases. Because there are a variety of tools, methods, and techniques that have been used in the studies that were reviewed, it is difficult to evaluate them using established standards. However, ultrasonography correlates well with clinical evaluation of dysphagia and therefore has prognostic and rehabilitation potential. Future studies should aim to develop and utilize a common interdisciplinary protocol that includes standard procedures and outcomes to define normative values applicable in the different conditions.

Reliability of Ultrasound Examination of Hyoid Bone Displacement Amplitude: A Systematic Review and Meta-Analysis

In swallowing, the hyoid bone moves up and forward in response to the activation of suprahyoid muscles, opening the upper esophageal sphincter and aiding the airway protection mechanism. This displacement measure has been analyzed with ultrasound images because this method does not expose the patient to radiation, has a good cost-benefit ratio, and is safe for the patient. However, there is no consensus on the reliability of this ultrasound measure. The objective of this study was to analyze the reliability of measuring hyoid bone displacement amplitude in swallowing with ultrasound. The systematic review encompassed five databases (MEDLINE, Scopus, EMBASE, Web of Science, Cochrane Library) and gray literature. There was no limitation of language or year of publication. The search/selection/extraction methodology was conducted by two authors blindly and independently, and differences were solved by a third rater. Three studies met the eligibility criteria: two of them analyzed the reliability in non-dysphagic populations and the other, in dysphagic patients. The transducer was positioned in the submandibular region in all studies. The authors were not clear about the training time to acquire and analyze ultrasound images. The meta-analysis had an interrater reliability of 0.858 (95% CI: 0.744-0.924) and intrarater reliability of 0.968 (95% CI: 0.903-0.990). There was, however, heterogeneity of p = 0.005 for intrarater reliability. Despite good reliability, the heterogeneity reinforces the importance of training and protocol standardization for image acquisition and analysis.

Tongue Contour Tracking and Segmentation in Lingual Ultrasound for Speech Recognition: A Review

Lingual ultrasound imaging is essential in linguistic research and speech recognition. It has been used widely in different applications as visual feedback to enhance language learning for non-native speakers, study speech-related disorders and remediation, articulation research and analysis, swallowing study, tongue 3D modelling, and silent speech interface. This article provides a comparative analysis and review based on quantitative and qualitative criteria of the two main streams of tongue contour segmentation from ultrasound images. The first stream utilizes traditional computer vision and image processing algorithms for tongue segmentation. The second stream uses machine and deep learning algorithms for tongue segmentation. The results show that tongue tracking using machine learning-based techniques is superior to traditional techniques, considering the performance and algorithm generalization ability. Meanwhile, traditional techniques are helpful for implementing interactive image segmentation to extract valuable features during training and postprocessing. We recommend using a hybrid approach to combine machine learning and traditional techniques to implement a real-time tongue segmentation tool.

Regional Variation in Contractile Patterns and Muscle Activity in Infant Pig Feeding

At the level of the whole muscle, contractile patterns during activity are a critical and necessary source of variation in function. Understanding if a muscle is actively lengthening, shorting, or remaining isometric has implications for how it is working to power a given behavior. When feeding, the muscles associated with the tongue, jaws, pharynx, and hyoid act together to transport food through the oral cavity and into the esophagus. These muscles have highly coordinated firing patterns, yet also exhibit high levels of regional heterogeneity in both their timing of activity and their contractile characteristics when active. These high levels of variation make investigations into function challenging, especially in systems where muscles power multiple behaviors. We used infant pigs as a model system to systematically evaluate variation in muscle firing patterns in two muscles (mylohyoid and genioglossus) during two activities (sucking and swallowing). We also evaluated the contractile characteristics of mylohyoid during activity in the anterior and posterior regions of the muscle. We found that the posterior regions of both muscles had different patterns of activity during sucking versus swallowing, whereas the anterior regions of the muscles did not. Furthermore, the anterior portion of mylohyoid exhibited concentric contractions when active during sucking, whereas the posterior portion was isometric during sucking and swallowing. This difference suggests that the anterior portion of mylohyoid in infant pigs is functioning in concert with the tongue and jaws to generate suction, whereas the posterior portion is likely acting as a hyoid stabilizer during sucking and swallowing. Our results demonstrate the need to evaluate both the contractile characteristics and activity patterns of a muscle in order to understand its function, especially in cases where there is potential for variation in either factor within a single muscle.