1Department of Medicine, Keimyung University School of Medicine, Daegu, Korea
2Department of Rehabilitation Medicine, Keimyung University Dongsan Hospital, Keimyung University School of Medicine, Daegu, Korea
Correspondence: Kyoung Tae Kim Department of Rehabilitation Medicine, Keimyung University Dongsan Hospital, Keimyung University School of Medicine, 1035 Dalgubeol-daero, Dalseo-gu, Daegu 42601, Korea. Tel: +82-53-258-7692 Fax: +82-53-258-4803 E-mail: zealot42@dsmc.or.kr
*These authors contributed equally to this work.
• Received: September 29, 2025 • Revised: January 2, 2026 • Accepted: January 22, 2026
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (https://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
To explore whether ultrasonographic measurements of tongue thickness are associated with swallowing function and related clinical domains in patients with amyotrophic lateral sclerosis (ALS), this feasibility study was conducted. Few studies have examined the usefulness of ultrasonographic tongue thickness measurement in patients with ALS, but its association with physiological measures remains unclear.
Methods
Ten patients with ALS underwent tongue thickness measurement using ultrasonography. Clinical assessments including the Korean version of the ALS Functional Rating Scale-Revised (K-ALSFRS-R), Functional Oral Intake Scale (FOIS), Eating Assessment Tool-10 (EAT-10), Dysphagia Handicap Index, Korean version of the Swallowing Quality of Life Questionnaire, Mini Nutritional Assessment–Short Form (MNA-SF), handgrip strength, and bioelectrical impedance analysis for skeletal muscle index (SMI) were performed. Swallowing physiology was evaluated using the Modified Barium Swallow Impairment Profile (MBSImP), Penetration-Aspiration Scale. Simple and partial Pearson’s correlation analyses as well as univariate regression were performed with adjustments for age, sex, and body mass index (BMI).
Results
Tongue thickness showed significant associations with multiple functional and systemic measures in the unadjusted analyses, including FOIS, EAT-10, MNA-SF, BMI, SMI, K-ALSFRS-R. After adjustment, the most consistent associations were observed with the MBSImP oral, pharyngeal, and combined phase scores.
Conclusion
Tongue ultrasonography may serve as a radiation-free method to preliminarily assess bulbar involvement in ALS. Tongue thickness was most specifically associated with dysphagia outcomes, particularly MBSImP. Given the feasibility design and small sample size, larger longitudinal studies are warranted to confirm its clinical utility in monitoring the progression of dysphagia in patients with ALS.
Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder characterized by the degeneration of upper and lower motor neurons, resulting in muscle weakness, dysphagia, and respiratory failure [1]. Among these clinical manifestations, dysphagia represents a major complication that affects disease progression and lowers quality of life. It also increases the risk of aspiration pneumonia, which is a leading cause of mortality in patients with ALS [2].
ALS is characterized by progressive atrophy of skeletal muscles [3], including the tongue, which commonly leads to tongue atrophy and dysfunction [4]. Dysphagia in ALS is predominantly neurogenic in origin. Progressive degeneration of upper and lower motor neurons disrupts innervation of oropharyngeal and tongue musculature, leading to denervation-induced muscle atrophy, motor unit loss, fasciculations, and impaired coordination of swallowing muscles [5]. Tongue atrophy leads to swallowing difficulties that cause subsequent nutritional decline, making the patient population more vulnerable [6]. Thus, reduced tongue thickness might be a non-invasive indicator of dysphagia; however, this requires further validation.
The ultrasonographic measurement of tongue thickness is being increasingly used in dysphagia evaluation by quantifying both static and dynamic anatomical features of the tongue, and prior studies have indicated its utility in identifying swallowing dysfunction caused by tongue atrophy [7]. In their systematic review, Potente et al. [7] emphasized that ultrasonography can provide valuable quantitative and qualitative information for assessing neurogenic dysphagia.
To date, limited studies have systematically examined the relationship between ultrasonographic tongue thickness and a broad range of swallowing assessments in patients with ALS. Furthermore, its association with physiological measures such as the Modified Barium Swallow Impairment Profile (MBSImP), nutritional indices, pulmonary function, and patient-reported outcomes remains unclear. Therefore, the present feasibility study aimed to assess the relationship between ultrasonographic tongue thickness and complementary clinical and functional measures of swallowing impairment in patients with ALS.
METHODS
Study design and participants
This cross-sectional observational study was conducted at a tertiary hospital between December 24, 2021, and December 23, 2022. Patients clinically diagnosed with ALS who visited the outpatient clinic during the study period were screened for eligibility. The inclusion criteria were as follows: (1) diagnosis of ALS according to the revised El Escorial criteria from the World Federation of Neurology; (2) presence of clinical symptoms of dysphagia; (3) age≥19 years; and (4) the ability to provide informed consent. The exclusion criteria were as follows: (1) severe cognitive impairment precluding participation in the modified barium swallowing study (MBSS) and patient report outcome measurement; (2) inability to maintain a seated posture; (3) uncontrolled systemic illnesses or significant comorbidities; and (4) neurological or structural disorders independently responsible for dysphagia.
The study protocol was approved by the local Institutional Review Board of Keimyung University Dongsan Medical Center (IRB No. 2021-12-025), and all the procedures were conducted in accordance with the Declaration of Helsinki. Written informed consent was obtained from all participants or their caregivers before enrollment.
Clinical assessment and outcome measurement
Baseline demographics, including age, sex, height, weight, body mass index (BMI), and the Korean version of the ALS Functional Rating Scale-Revised (K-ALSFRS-R), were collected prior to study enrollment. The K-ALSFRS-R is a validated tool that assesses functional status across the bulbar, motor, and respiratory domains in patients with ALS, with total scores ranging from 0 to 48 [8].
Ultrasonographic measurement of tongue thickness
Ultrasound sonographic evaluation was performed using a C5-1 convex array transducer with Affiniti 70 ultrasound system (Philips Healthcare) operating at a central frequency range of 1–5 MHz. The participants were seated comfortably with their heads in a neutral position and slightly leaned backward at approximately 30° to standardize the imaging angle. To ensure relaxation and minimize measurement variability, the participants were instructed to keep their neck muscles relaxed, maintain the tongue in a resting position without pressing it against the palate, and avoid any voluntary tongue movement during the scan. For consistent imaging, the transducer was placed perpendicular to the Frankfurt horizontal plane (Fig. 1). Tongue thickness was measured in coronal and midsagittal views, which allowed clear visualization of the anatomical landmarks, including the mandible, hyoid bone, mylohyoid muscle, geniohyoid muscle, and tongue dorsum.
Ultrasonography was first performed in the midsagittal plane, enabling simultaneous visualization of the mandibular symphysis anteriorly and the hyoid bone posteriorly to confirm proper midline alignment. After positioning the probe at the midpoint of an imaginary line connecting the mandible and the hyoid bone, the probe was rotated 90° to obtain a coronal view (Fig. 2A). This measurement protocol was adapted from previously published ultrasonographic studies in patients with ALS that employed a midline approach using the mandible and hyoid bone as anatomical landmarks [9]. The ultrasound images were transferred to ImageJ software (National Institutes of Health) for quantitative measurements. The tongue thickness was defined as the perpendicular distance from the surface of the mylohyoid muscle to the dorsum of the tongue (Fig. 2B). Representative ultrasonographic images of patients with varying degrees of tongue atrophy are shown in Fig. 2C (mild) and 2D (severe).
Quantitative assessment of dysphagia severity
Swallowing function was primarily assessed using the MBSImP, a validated and standardized scoring protocol that evaluates 17 physiological components across the oral, pharyngeal, and esophageal domains [10]. To obtain the MBSImP scores, all participants underwent the MBSS, which provided dynamic fluoroscopic visualization of bolus transit and structural movement during swallowing. Standardized boluses of varying consistency and volume, including thin liquid, nectar-thick, honey-thick liquids, and pureed and solid textures, each mixed with barium sulfate, were administered following a predetermined sequence designed to simulate typical eating and drinking tasks [11]. Swallows were observed in both the lateral and anterior–posterior views, and the worst observed performance for each component was scored using the MBSImP ordinal scale (0–2, 3, or 4, depending on the parameter). Composite scores were then calculated as the Oral Total Score (maximum=22), Pharyngeal Total Score (maximum=29), and Esophageal Score (maximum=4). Moreover, aspiration risk was assessed using the Penetration-Aspiration Scale (PAS) during the swallowing study [12].
Clinical and functional outcome measures
To comprehensively evaluate the oral intake status, dysphagia severity, swallowing-related quality of life, nutritional status, muscle strength, and pulmonary function, a series of validated clinical assessments was performed. All the questionnaires were administered face-to-face by a trained assessor. When patients were unable to complete the questionnaires owing to physical limitations, responses were obtained from their primary caregivers.
The oral intake status was evaluated using the Functional Oral Intake Scale (FOIS), a 7-point ordinal scale ranging from level 1 (nothing by mouth) to level 7 (total oral intake without restrictions). The severity of dysphagia was assessed using two validated self-report tools [13]. The Dysphagia Handicap Index comprises 25 items evaluating the physical, emotional, and functional impact of dysphagia, with scores ranging from 0 (never) to 4 (always), with higher scores indicating a greater handicap [14]. The Eating Assessment Tool-10 (EAT-10) is a 10-item questionnaire with total scores ranging from 0 to 40, and a score of 3 or higher indicates clinically significant dysphagia [15]. Swallowing-related quality of life was assessed using the Korean version of the Swallowing Quality of Life Questionnaire (K-SWAL-QOL), a 44-item instrument covering 11 domains. Items were rated on a 5-point Likert scale, and normalized scores were calculated using the original scoring algorithm [16]. Nutritional status was assessed using the Mini Nutritional Assessment–Short Form (MNA-SF), which evaluates recent dietary intake, weight loss, mobility, psychological stress, neuropsychological issues, and BMI. The total score ranges from 0 to 14, with scores below 8 indicating malnutrition [17].
Body composition, including skeletal muscle index (SMI), was measured using a multifrequency bioelectrical impedance analyzer (InBody BWA 2.0; InBody Co.). Because some patients were unable to stand unassisted due to weakness, the supine mode of the device was used to allow measurements in the lying position. SMI was derived as appendicular lean mass divided by the square of height (ALM/height2, kg/m2). Pulmonary function was assessed with standard spirometry, and forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1) were recorded.
Two independent assessors participated in this study: one clinician certified in the MBSImP scoring through Northern Speech Services [10], and a second assessor responsible for ultrasonographic acquisition and quantitative analysis. The ultrasonography assessor was blinded to all swallowing parameters, clinical information, and MBSImP results. Conversely, the MBSImP-certified assessor was blinded to the ultrasonographic measurements.
Statistical analysis
Descriptive statistics were used to summarize the demographic and clinical characteristics. Continuous variables are presented as mean±standard deviation, and categorical variables as frequencies and percentages. Pearson correlation analyses were performed to assess the relationship between tongue thickness and clinical variables related to functional status, swallowing, pulmonary function, and SMI. Both simple and partial Pearson’s correlations (controlling for age, sex, and BMI) were calculated.
Additionally, univariate regression analyses were performed to further examine the independent associations between tongue thickness and the clinical variables that showed the strongest correlations in previous analyses. In these models, tongue thickness was entered as the dependent variable, whereas each selected clinical measure was analyzed separately as an independent variable, with adjustments for age, sex, and BMI. The regression coefficients were calculated with 95% confidence intervals (CIs). Statistical significance was set at p<0.05. All statistical analyses were performed using IBM Statistical Package for the Social Sciences Statistics (version 21.0; IBM Corp.).
RESULTS
In total, 10 patients with ALS with a mean age of 66.70±9.41 (three females and seven males) were enrolled (Table 1). The cohort was predominantly limb-onset (8 out of 10), whereas only two had bulbar-onset disease. Mean ALSFRS-R score (28.80±8.63) indicated mild to moderate functional impairment. Pulmonary function was also reduced, with average FVC and FEV1 values corresponding to the mild-to-moderate impairment. At baseline, the PAS scores ranged from 1 to 8, with a mean±standard deviation of 3.1±2.2. The distribution of PAS scores was as follows: PAS score 1 in one patient; 2 in six patients; and 4, 6, and 8 in three patients each.
Compared with the published normative data from healthy older adults (mean tongue thickness, 4.48±0.30 cm) [9], our ALS cohort had a lower mean thickness (4.04±0.40 cm) (Table 2). Although our study lacked a control group, this difference—using age- and ethnicity-comparable reference values—suggests that reduced tongue thickness in these patients may reflect tongue atrophy associated with ALS. Patients reported swallowing difficulties with a mean EAT-10 score of 20.20, whereas oral intake was relatively preserved (FOIS 5.50±0.85). The mean K-SWAL-QOL score was 60.47, indicating a measurable impact of dysphagia on the quality of life, and the MNA-SF score averaged 8.60, suggesting a reduced nutritional status in this cohort.
On MBSImP evaluation, dysphagia was more severe in the oral phase (9.60±2.67) than in the pharyngeal phase (7.50±3.66), indicating prominent oral phase involvement. Significant associations were observed between tongue thickness and several functional and nutritional parameters (Table 3). Regarding dysphagia severity, tongue thickness was negatively correlated with oral phase score (r=-0.649, 95% CI=-0.908 to -0.033, p=0.042) and oral+pharyngeal phase score (r=-0.827, 95% CI=-0.958 to -0.412, p=0.003). After adjusting for age, sex, and BMI, functional indices, including the FOIS and SMI, showed only trend-level associations (p=0.06) and were not statistically significant. However, tongue thickness showed significant associations with the MBSImP oral phase score (r=-0.816, 95% CI=-0.955 to -0.383, p=0.025), oral+pharyngeal phase score (r=-0.933, 95% CI=-0.984 to -0.735, p=0.002). Notably, the pharyngeal phase score, which was not significant in the unadjusted analysis (r=-0.368, 95% CI=-0.810 to -0.341, p=0.296), became highly significant after adjustment (r=-0.891, 95% CI -0.974 to -0.595, p=0.007).
In simple regression analysis, significant associations were consistently observed with swallowing impairment scores (Table 4) . Tongue thickness showed a significant negative relationship with the MBSImP oral phase score (B=-0.119, 95% CI=-0.216 to -0.022, p=0.025). Additionally, a strong negative association was observed with the combined oral and pharyngeal phase score (B=-0.075, 95% CI=-0.108 to -0.042, p=0.002), indicating robust associations with swallowing dysfunction severity.
DISCUSSION
Our findings suggest that ultrasonographic tongue thickness is associated with several clinical and functional measures in patients with ALS. Higher tongue thickness was associated with a more favorable patient-reported swallowing status (lower EAT-10 and higher FOIS), higher nutritional indices (MNA-SF and BMI), higher SMI, ALSFRS-R, and enhanced pulmonary function in unadjusted analyses. However, after adjusting for age, sex, and BMI, these associations were attenuated, and the MBSImP scores remained the most consistent correlates.
The MBSS is the gold standard for evaluating dysphagia and is widely performed in patients [18,19]. However, its reliance on fluoroscopy and radiation exposure is a concern for repeated monitoring [20]. Because ALS is characterized by the rapid progression of bulbar and swallowing dysfunction, evaluations are often needed at shorter intervals compared to other dysphagic populations. Consequently, the potential risks of cumulative radiation exposure and aspiration during fluoroscopy may be of particular concern for patients with ALS.
Ultrasonographic measurement of tongue thickness has emerged as a noninvasive and reliable method for assessing the structural and functional status of the tongue musculature [21]. Ultrasonography has its own advantages, allowing real-time visualization of tongue morphology and providing objective quantitative data that can be easily obtained even at the bedside without radiation exposure. Tongue thickness measured using ultrasonography correlates well with swallowing function in healthy older adults [22], patients with sarcopenia, and individuals with neuromuscular disorders, such as Parkinson’s disease or stroke [7]. Similarly, our study showed that tongue thickness was strongly associated with MBSImP oral phase scores, suggesting a potential relationship with oral phase dysfunction, which is particularly relevant in ALS, where bolus manipulation and propulsion are often compromised [9].
Tongue thickness is correlated with the FOIS, indicating that greater tongue muscle bulk may be related to safer and more efficient oral intake. The correlation with FOIS did not persist after adjusting for age, sex, and BMI, suggesting confounding by age and nutritional status. Thus, FOIS likely reflects influences beyond bulbar morphology. Older patients with ALS are more likely to experience reduced oral intake from bulbar weakness and age-related sarcopenia, frailty, and comorbidities, which negatively affect swallowing outcomes [23]. Moreover, nutritional status is a key determinant of FOIS in individuals with dysphagia, with malnutrition and low muscle mass strongly linked to reduced oral intake [24]. Collectively, these findings suggest that the FOIS is influenced by a combination of bulbar morphology, aging, and nutritional status rather than by tongue thickness alone.
In our cohort, tongue thickness positively correlated with pulmonary function parameters, including FVC and FEV1. This finding supports a clinical association between respiratory capacity and swallowing function, as both domains are commonly impaired in ALS [25]. Notably, FVC has been associated with voluntary cough effectiveness and airway protection in patients with ALS, and diminished expiratory metrics have been observed in those demonstrating unsafe swallowing [26]. These observations are consistent with the broader finding that bulbar motor deterioration in ALS significantly impairs speech and swallowing. Nevertheless, these associations were attenuated in the adjusted analyses, underscoring that bulbar muscle integrity appears to be the most specific contributor to swallowing impairment.
The relationship between tongue thickness and swallowing impairment, particularly MBSImP oral and pharyngeal phase scores, remained robust even after adjustment. In the regression models, MBSImP was the only measure that consistently demonstrated a strong independent association with tongue thickness. This indicates that tongue ultrasonography may reflect broader clinical associations at an unadjusted level; however, the most consistent and specific correlate in this study was swallowing physiology itself [9].
We observed that thinner tongues in patients with ALS were associated with a lower SMI and poorer nutritional indices. This suggests that tongue thickness may be related to systemic muscle status in ALS. Although individuals with ALS may exhibit generalized muscle loss with disease progression, the structural changes observed in the tongue are primarily a consequence of impaired neural input. Denervation, rather than age-related sarcopenic mechanisms, is the primary driver of tongue atrophy in ALS. Thus, even when tongue thickness appears to be related to systemic muscle parameters, its underlying biology represents neurogenic degeneration secondary to motor neuron loss rather than age-associated muscular decline. Consistent with these findings, Maeda et al. [27] reported that reduced tongue thickness and tongue pressure are associated with malnutrition and impaired oral intake in frail older adults, as well as with systemic muscle loss in neuromuscular disorders.
Nakamori et al. [9] demonstrated that ultrasonographically measured tongue thickness was significantly reduced in patients with ALS compared with healthy controls and was associated with both swallowing impairment and nutritional status. Specifically, reduced tongue thickness was associated with oral preparatory and oral transit times on videofluoroscopic swallowing studies, indicating a predominant association with oral phase dysfunction. In agreement with these findings, the present study demonstrated that reduced tongue thickness was consistently associated with greater oral-phase impairment, as reflected by higher MBSImP oral-phase scores. Cumulatively, these findings support the notion that ultrasonographically measured tongue thickness reflects lingual dysfunction related to bulbar involvement in ALS, particularly affecting oral phase swallowing physiology.
However, notable differences exist between the results of the present study and those reported by Nakamori et al. [9]. While Nakamori et al. [9] did not identify a significant association between tongue thickness and pharyngeal transit time, our study demonstrated significant associations between reduced tongue thickness and both oral and pharyngeal phase impairment scores on the MBSImP after adjustment for age, sex, and BMI. This discrepancy may be explained by differences in the swallowing assessment methodology. Nakamori et al. [9] relied on temporal measures of bolus transit, which primarily capture timing aspects of swallowing, whereas the MBSImP provides a component-based evaluation of swallowing physiology, including structural movement and coordination during the pharyngeal phase. Resultantly, the present study may have been more sensitive to detecting subtle pharyngeal dysfunction associated with lingual weakness. Additionally, differences in sample size, disease stage distribution, and analytical approaches may have contributed to variations in observed associations.
This study had several limitations. First, the sample size was small (n=10), which inherently limited the statistical power and generalizability. Adjusting for multiple covariates in such a small sample carries a substantial risk of statistical overfitting; therefore, any significant associations should be regarded as exploratory. For this reason, we limited the number of covariates in the regression model to minimize overfitting. Moreover, the limited number of participants made it difficult to apply regression analyses to reliably determine the causal relationships between the variables. Second, longitudinal follow-up could not be conducted, largely because of the rapid progression and poor prognosis of ALS, which makes sustained participation difficult as patients frequently experience clinical deterioration, loss to follow-up, or death. Third, in our study, tongue thickness was assessed only at rest. Although resting measurements are commonly used and allow standardized acquisition, dynamic assessments during swallowing or maximal voluntary contraction may provide additional information regarding functional tongue reserve and coordination, and should be explored in future studies. Moreover, tongue fasciculations, a key ultrasonographic indicator of neurogenic atrophy in ALS, were not evaluated, representing a methodological limitation. Furthermore, inter-rater or intra-rater reliability was not assessed for ultrasonographic measurements, which may affect the consistency of our findings. Finally, the absence of a healthy, age-matched control group precluded direct comparison with normative tongue thickness values and limited interpretation of whether the observed measurements reflect true atrophy relative to baseline population data.
In conclusion, this study suggests that the ultrasonographic measurement of tongue thickness may provide preliminary insight into bulbar dysfunction in ALS. This feasibility study indicates that tongue ultrasonography could be explored further as a non-invasive, radiation-free tool for evaluating dysphagia in patients with ALS. Larger sample size studies with appropriate comparison groups will be necessary to determine whether tongue ultrasonography has meaningful clinical value in ALS dysphagia assessment.
CONFLICTS OF INTEREST
No potential conflict of interest relevant to this article was reported.
FUNDING INFORMATION
None.
AUTHOR CONTRIBUTION
Conceptualization: Kim MS, Nam Y, Kim KT. Data curation: Nam Y. Investigation: Kim KT. Methodology: Kim MS, Kim KT. Formal analysis: Nam Y. Project Administration: Kim KT. Resources: Kim KT. Visualization: Kim MS, Nam Y. Supervision: Kim KT. Writing – original draft: Kim MS, Nam Y. Writing – review and editing: Kim KT. Approval of final manuscript: all authors.
Fig. 1.
Protocol of ultrasonographic tongue thickness measurement. Probe is positioned between mandible and hyoid bone, perpendicular to the Frankfurt horizontal line.
Fig. 2.
Ultrasound imaging of the tongue thickness measurement. (A) Midsagittal long axis view of tongue. (B) Tongue thickness was measured from the mylohyoid muscle to the tongue dorsum in short axis view. (C) Mild tongue atrophy. (D) Severe tongue atrophy.
Table 1.
Baseline characteristics of patients with ALS
Patient characteristic
ALS (N=10)
Age (yr)
66.70±9.41
Sex
Female
3
Male
7
Body mass index (kg/m2)
21.26±4.73
Duration from onset (mo)
29.10±17.73
ALSFRS-R
28.80±8.63
Onset site
Bulbar
2
Limb
8
PFT
FEV1
74.70±25.63
FVC
63.80±27.12
BMD (T-score)
-2.30±1.59
SMI
5.07±1.31
PAS
3.1±2.2
Values are presented as mean±standard deviation or number only.
ALS, amyotrophic lateral sclerosis; ALSFRS-R, ALS Functional Rating Scale-Revised; PFT, pulmonary function test; FEV1, forced expiratory volume in 1 second; FVC, forced vital capacity; BMD, bone mineral density; SMI, skeletal muscle index; PAS, Penetration-Aspiration Scale.
Table 2.
Ultrasonography and clinical assessments
ALS (N=10)
Tongue thickness (cm)
4.04±0.40
EAT-10
20.20±10.53
FOIS
5.50±0.85
K-SWAL-QOL
60.47±13.66
MNA-SF
8.60±3.50
DHI
40.60±19.96
MBSImP score
Oral phase
9.60±2.67
Pharyngeal phase
7.50±3.66
Oral+pharyngeal phase
17.1±3.73
Values are presented as mean±standard deviation.
ALS, amyotrophic lateral sclerosis; EAT-10, Eating Assessment Tool-10; FOIS, Functional Oral Intake Scale; K-SWAL-QOL, Korean version of the Swallowing Quality of Life Questionnaire; MNA-SF, Mini Nutritional Assessment–Short Form; DHI, Dysphagia Handicap Index; MBSImP, Modified Barium Swallow Impairment Profile.
Table 3.
Correlation between tongue thickness and clinical variables (simple and adjusted analyses)
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Ultrasonographic Measurements of Tongue Thickness and Swallowing Dysfunction in Amyotrophic Lateral Sclerosis: A Feasibility Study
Fig. 1. Protocol of ultrasonographic tongue thickness measurement. Probe is positioned between mandible and hyoid bone, perpendicular to the Frankfurt horizontal line.
Fig. 2. Ultrasound imaging of the tongue thickness measurement. (A) Midsagittal long axis view of tongue. (B) Tongue thickness was measured from the mylohyoid muscle to the tongue dorsum in short axis view. (C) Mild tongue atrophy. (D) Severe tongue atrophy.
Graphical abstract
Fig. 1.
Fig. 2.
Graphical abstract
Ultrasonographic Measurements of Tongue Thickness and Swallowing Dysfunction in Amyotrophic Lateral Sclerosis: A Feasibility Study
Patient characteristic
ALS (N=10)
Age (yr)
66.70±9.41
Sex
Female
3
Male
7
Body mass index (kg/m2)
21.26±4.73
Duration from onset (mo)
29.10±17.73
ALSFRS-R
28.80±8.63
Onset site
Bulbar
2
Limb
8
PFT
FEV1
74.70±25.63
FVC
63.80±27.12
BMD (T-score)
-2.30±1.59
SMI
5.07±1.31
PAS
3.1±2.2
ALS (N=10)
Tongue thickness (cm)
4.04±0.40
EAT-10
20.20±10.53
FOIS
5.50±0.85
K-SWAL-QOL
60.47±13.66
MNA-SF
8.60±3.50
DHI
40.60±19.96
MBSImP score
Oral phase
9.60±2.67
Pharyngeal phase
7.50±3.66
Oral+pharyngeal phase
17.1±3.73
Variable
Simple correlation (r, 95% CI)
p-value
Adjusted correlationa) (r, 95% CI)
p-value
ALSFRS-R
0.691 (0.109 to 0.920)
0.027*
0.167 (-0.517 to 0.721)
0.721
FOIS
0.645 (0.026 to 0.906)
0.044*
0.732 (0.190 to 0.932)
0.061
ASHA NOMS
0.637 (0.012 to 0.904)
0.048*
0.557 (-0.112 to 0.879)
0.194
FVC
0.747 (0.222 to 0.936)
0.013*
0.323 (-0.385 to 0.792)
0.48
FEV1
0.701 (0.128 to 0.923)
0.024*
0.064 (-0.589 to 0.667)
0.892
SMI
0.729 (0.184 to 0.931)
0.017*
0.735 (0.196 to 0.933)
0.060
MBSImP score
Oral phase
-0.649 (-0.908 to -0.033)
0.042*
-0.816 (-0.955 to -0.383)
0.025*
Pharyngeal phase
-0.368 (-0.810 to -0.341)
0.296
-0.891 (-0.974 to -0.595)
0.007**
Oral+pharyngeal phase
-0.827 (-0.958 to -0.412)
0.003**
-0.933 (-0.984 to -0.735)
0.002**
Variable
B
95% CI
p-value
MBSImP
Oral phase
-0.119
-0.216 to -0.022
0.025*
Oral+pharyngeal phase
-0.075
-0.108 to -0.042
0.002**
Table 1. Baseline characteristics of patients with ALS
Values are presented as mean±standard deviation or number only.
ALS, amyotrophic lateral sclerosis; ALSFRS-R, ALS Functional Rating Scale-Revised; PFT, pulmonary function test; FEV1, forced expiratory volume in 1 second; FVC, forced vital capacity; BMD, bone mineral density; SMI, skeletal muscle index; PAS, Penetration-Aspiration Scale.
Table 2. Ultrasonography and clinical assessments
Values are presented as mean±standard deviation.
ALS, amyotrophic lateral sclerosis; EAT-10, Eating Assessment Tool-10; FOIS, Functional Oral Intake Scale; K-SWAL-QOL, Korean version of the Swallowing Quality of Life Questionnaire; MNA-SF, Mini Nutritional Assessment–Short Form; DHI, Dysphagia Handicap Index; MBSImP, Modified Barium Swallow Impairment Profile.
Table 3. Correlation between tongue thickness and clinical variables (simple and adjusted analyses)
Values are presented as Pearson correlation coefficients (r) with 95% confidence intervals (CIs).
ALSFRS-R, Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised; FOIS, Functional Oral Intake Scale; ASHA NOMS, American Speech-Language-Hearing Association National Outcome Measurement System; FVC, forced vital capacity; FEV1, forced expiratory volume in 1 second; SMI, skeletal muscle index; MBSImP, Modified Barium Swallow Impairment Profile; BMI, body mass index.
Adjusted for age, sex, and BMI.
p<0.05 and
p<0.01.
Table 4. Univariate regression analysis
Regression coefficients (B) were obtained from linear regression models adjusted for age, sex, and BMI.
CI, confidence interval; MBSImP, Modified Barium Swallow Impairment Profile; BMI, body mass index.
