Analysis of the suprahyoid muscles during tongue elevation: High-density surface electromyography as a novel tool for swallowing-related muscle assessment.

BACKGROUND: High-density surface electromyography (HD-sEMG) has enabled non-invasive analysis of motor unit (MU) activity and recruitment, but its application to swallowing-related muscles is limited. OBJECTIVE: We aimed to investigate the utility of HD-sEMG for quantitatively evaluating the MU recruitment characteristics of the suprahyoid muscles during tongue elevation. METHODS: We measured the sEMG activity of the suprahyoid muscles of healthy participants during tongue elevation using HD-sEMG. Maximum voluntary contraction (MVC) was measured, followed by data collection during sustained and ramp-up tasks to capture suprahyoid muscle activity. Changes in the temporal/spatial MU recruitment patterns within individual suprahyoid muscles were analysed. RESULTS: This study enrolled 16 healthy young adults (mean age: 27.8 ± 5.3 years; eight males and eight females). Increasing muscle force corresponded to a decrease in modified entropy and correlation coefficient and an increase in the coefficient of variation. No significant differences were observed between male and female participants. CONCLUSION: The results of this study, consistent with those observed in other muscles, such as the vastus lateralis muscle, suggest that HD-sEMG is a valuable and reliable tool for quantitatively evaluating MU recruitment in the suprahyoid muscles. This measurement technique holds promise for novel assessments of swallowing function.

Association of Baseline Skeletal Muscle Mass Index With Adverse Events and Rehabilitation Outcomes in Patients Admitted for Rehabilitation.

Objective: To assess the associations of baseline skeletal muscle mass index (SMI) with adverse events and rehabilitation outcomes in patients admitted for rehabilitation. Design: A retrospective cohort study. Participants: The subjects were 409 patients (mean age, 79 years; men, 167 [41%]) undergoing rehabilitation because of neurologic disease, musculoskeletal disorders, or hospital-associated deconditioning. Patients were divided into 2 groups according to the definition of sarcopenia by the Asian Working Group for Sarcopenia: those with low SMI (<7.0 kg/m2 in men and <5.7 kg/m2 in women) and those with high SMI (≥7.0 kg/m2 in men and ≥5.7 kg/m2 in women). Interventions: Not applicable. Main Outcome Measures: The primary outcomes were adverse events including death and acute illness requiring transfer to other hospitals for specialized treatments. The secondary outcomes were rehabilitation outcomes including the efficiency scores (changes in functional independence measure [FIM] score divided by length of stay) of FIM for motor function (FIM-M) and FIM for cognitive function (FIM-C). Results: Of the 409 patients, 299 (73%) had a low SMI. The adjusted hazard ratio (95% confidence interval) of the low SMI group relative to the high SMI group for adverse events was 2.79 (1.06-7.34). There were no significant differences between the 2 groups in FIM-M efficiency scores [mean ± SD, low SMI group: 0.4 (0.58) vs high SMI group: 0.47 (0.54), P=.3] and FIM-C efficiency scores [mean ± SD, 0.05 (0.14) vs 0.06 (0.2), P=.4]. Multiple linear regression models did not show significant associations between the low SMI group and FIM-M efficiency or FIM-C efficiency scores (ß=0.064, P=.3; ß=-0.05, P=.4, respectively). Conclusion: Low baseline SMI was significantly associated with adverse events but not with rehabilitation outcomes in patients undergoing rehabilitation.

Quantitative evaluation of swallowing function in Parkinson's disease using tongue pressure measurement: a mini-review.

Dysphagia is a common symptom of Parkinson's disease (PD) associated with aspiration pneumonia, choking, malnutrition, and a decreased quality of life, and is a leading cause of death among patients with PD. Tongue dysfunction in patients with PD affects the oral phase of swallowing, including the formation and propulsion of a bolus into the pharynx. Assessing tongue pressure, generated between the tongue and palate, is a method that quantitatively measures tongue function and is related to dysphagia in PD. Two assessment methods are used to measure tongue pressure: tongue strength and tongue pressure during swallowing. Previous studies measuring tongue pressure in PD have reported decreased tongue strength and pressure during swallowing, as well as a prolonged tongue pressure rise time, which are symptoms associated with PD severity and dysphagia. In this mini-review, we present a method for measuring tongue pressure and discuss its relationship with dysphagia in PD. We also describe limitations and future perspectives in tongue pressure measurement research.

Effects of Tongue-Strengthening Exercise on Tongue Strength and Effortful Swallowing Pressure in Young Healthy Adults: A Pilot Study.

PURPOSE: The purpose of this study was to investigate the effects of tongue-strengthening exercise (TSE) on tongue strength and effortful swallowing pressure in young healthy adults. METHOD: Thirteen young healthy volunteers (six men, seven women; M age = 20.5 ± 0.5 years) performed 8 weeks of isometric TSE 3 days per week. A tongue pressure measurement device was used to measure maximum isometric tongue pressure (MITP) and conduct the TSE, and a tactile sensor system attached to the hard palate was used to measure effortful swallowing pressure. MITP and effortful swallowing pressure were measured at baseline, after 4 and 8 weeks of training, and at 4 and 8 weeks after the last training session to examine the detraining effects. RESULTS: The results indicated that both MITP and effortful swallowing pressure increased significantly from baseline to 8 weeks after training. Although the improved MITP significantly decreased at 4 and 8 weeks after training cessation, no detraining effect was observed for effortful swallowing pressure. CONCLUSIONS: TSE is an effective method for increasing tongue pressure in wide tongue-palate contact areas during effortful swallow. The effortful swallowing pressure gained with TSE appears to be maintained for at least eight nontraining weeks.

Comparison of the Iowa Oral Performance Instrument and JMS tongue pressure measurement device.

BACKGROUND/PURPOSE: Tongue pressure measurement conveys important information about eating and swallowing function. The Iowa Oral Performance Instrument® (IOPI) and KAY Swallowing Workstation® are internationally used for tongue pressure measurement, but for legal reasons cannot be used in Japan; rather the JMS tongue pressure measurement device® has been approved for use in Japan. However, it is not clear whether measurement obtained with these devices are directly comparable. MATERIALS AND METHODS: This study investigated the correlation between the maximum tongue pressure data measured by the IOPI and the JMS tongue pressure measurement device in young healthy participants (34 males; 23.2 ±â€¯2.0 years old, and 40 females; 21.4 ±â€¯1.3 years old). RESULTS: Measurements obtained with these two devices showed significant correlations in the total cohort, and in male and female participants, separately (P < 0.05). CONCLUSION: These findings demonstrate that the measurements obtained with the JMS device is comparable to those obtained with the IOPI. In Japan, JMS tongue pressure measurement device is used not only in dysphagia research field, but also geriatrics field, and extensive and detailed investigations has been carried out.

Association Between Active Gait Training for Severely Disabled Patients with Nasogastric Tube Feeding or Gastrostoma and Recovery of Oral Feeding: A Retrospective Cohort Study.

PURPOSE: This study evaluates the effect of introducing active gait training (AGT) to patients who are severely disabled with nasogastric tube feeding or gastrostoma on the recovery of oral feeding. PATIENTS AND METHODS: We conducted a historical cohort study at a single rehabilitation center in Japan between January 2013 and December 2019. In this study, 154 severely disabled patients with nasogastric tube feeding or gastrostoma due to neurological diseases or disuse syndrome admitted in a rehabilitation ward were included, and their median age was 84 years. AGT was systematically implemented in August 2016, which consisted of using orthosis or assistance from physical therapists. We compared the recovery of oral feeding between periods before (Pre-AGT) and after (Post-AGT) the introduction of AGT. RESULTS: Among the 154 severely disabled patients included, 59 (38%) were admitted in the Post-AGT period. Twenty-eight (30%) and 54 patients (92%) started gait training in the Pre-AGT and Post-AGT periods, respectively (p < 0.001). Significantly more patients recovered oral feeding in the Post-AGT than in the Pre-AGT periods (49% vs 19%, respectively; p < 0.001). After the introduction of AGT, the adjusted hazard ratio for the recovery of oral feeding was 4.0 (95% confidence interval, 1.9-8.3; p < 0.001). CONCLUSION: After the introduction of AGT to patients, increased recovery of oral feeding was observed in this retrospective evaluation. AGT should be considered for patients with tube feeding to help them recover oral feeding even if patients were severely disabled and required full assistance during gait training.

Tongue Pressure Measurement and Videofluoroscopic Study of Swallowing in Patients with Parkinson's Disease.

This study investigated the relationship between tongue pressure during swallowing and dysphagia in patients with Parkinson's disease (PD). A total of 24 patients with PD (12 men and 12 women, mean age 70.4 years) were studied. Their mean Hoehn and Yahr scale was 3.0 ± 1.3 (range 1-5). All participants underwent tongue pressure measurement and videofluorography during swallowing. Tongue pressure when swallowing 5 mL of barium on videofluorography was measured using a sensor sheet with five sensors. Based on the findings of videofluorography, the patients were divided into two groups: dysphagic PD group (n = 9) and non-dysphagic PD group (n = 15). The maximal magnitude (kPa), duration (s), time to peak pressure (s), and pressure gradient (kPa/s) of tongue pressure were analyzed for each part. For duration, time to peak pressure, and pressure gradient, similar values were calculated from the total waveform. There was no significant difference in maximal tongue pressure between the groups. The dysphagic PD group had prolonged duration of tongue pressure and time to peak pressure and a reduced pressure gradient compared with the non-dysphagic PD group. These results indicate that there is a clear difference in the temporal aspects of tongue pressure between the non-dysphagic and dysphagic PD patients. These differences provide the characteristics of tongue movement during swallowing in PD patients with dysphagia, which may be useful for the diagnosis and treatment of dysphagia.

Secondary Mania after Cerebral Infarction in the Recovery Phase: Case Report.

INTRODUCTION: Although patients commonly experience psychological disorders such as depression following cerebrovascular events, mania is extremely rare. Here we present a patient who experienced secondary mania while being hospitalized in a convalescent rehabilitation ward following cerebral infarction. CASE: The patient was a 70-year-old man who was hospitalized at our hospital for convalescent rehabilitation after suffering mild right hemiplegia and higher brain dysfunction following cerebral infarction. During hospitalization, the patient experienced a progression-free course. Upon awakening on day 26 after hospitalization, the patient suddenly showed signs of mania. The symptoms included elevated mood, pressured speech, hyperactivity, insomnia, and agitation; these symptoms caused problems in his daily life at the hospital. On day 29 after hospitalization, the patient was referred to a psychiatric hospital as an outpatient. He was diagnosed with organic manic disorder and was hospitalized. The patient was administered lithium carbonate (Limas®; 400 mg daily) and risperidone (Risperdal®; 2 mg daily). Because the mania persisted for more than 1 week, he was diagnosed with secondary mania. His manic state gradually improved, and he was transferred to our hospital. He was able to undergo rehabilitation without any problem and with no exacerbation of mania. The patient was discharged on day 139 after readmission. DISCUSSION: In cases where patients with cerebrovascular disorders display abnormal behavior, it becomes necessary to differentiate between secondary mania and social behavior disorder. Because mania has a negative impact on the patient's hospitalization and convalescence, if secondary mania is suspected, early consideration of psychiatric treatment is required.

Change in tongue pressure in patients with head and neck cancer after surgical resection.

Tongue pressure is reportedly associated with dysphagia. This study investigated relationships among characteristics of head and neck cancer, tongue pressure and dysphagia screening tests performed in patients with head and neck cancer during the acute phase after surgical resection. Fifty-seven patients (36 men, 21 women; age range 26-95 years) underwent surgical resection and dysphagia screening tests (Repetitive Saliva Swallowing Test, Water Swallowing Test, Modified Water Swallowing Test and Food Test) and pre- and postoperative measurement of tongue pressure at 5 time points (preoperatively, and 1-2 weeks and 1, 2, and 3 months postoperatively). Progression of cancer (stage), tracheotomy, surgical reconstruction, chemotherapy, radiotherapy and neck dissection were factors associated with postoperative tongue pressure. Data were analyzed by linear mixed-effect model, Spearman correlation coefficient and receiver operating characteristic (ROC) curve. Tongue pressure was significantly reduced 1-2 weeks after surgery, and recovered over time. Changes in tongue pressure were significantly associated with stage, radiotherapy and reconstruction. All screening tests showed a significant relationship with tongue pressure. Analysis of ROC and area under the effect curve suggested that a tongue pressure of 15 kPa can be used as a cut-off value to detect dysphagia after surgery for head and neck cancer. Our results suggest that tongue pressure evaluation might offer a safe, useful and objective tool to assess dysphagia immediately postoperatively in patients with head and neck cancer.

Effect of the effortful swallow and the Mendelsohn maneuver on tongue pressure production against the hard palate.

Although effortful swallow and the Mendelsohn maneuver are commonly used in dysphagia rehabilitation, little is known about their effects on tongue-palate pressure production. The purpose of this study was to investigate the effects of effortful swallow and the Mendelsohn maneuver on tongue pressure production. Fourteen healthy volunteers (10 men, 4 women; age range = 21-41 years) participated. Tongue pressures during dry swallow, water swallow, effortful swallow, and the Mendelsohn maneuver were measured using a sensor sheet system with five measurement points on the hard palate. Sequential order, duration, maximal magnitude, and the integrated value of tongue pressure at each measurement point were compared among the four tasks. Onset of tongue pressure at the posterior-circumferential parts occurred first in the Mendelsohn maneuver; that at the anterior-median part was earlier than at other parts in the effortful swallow. At all measurement points, tongue pressure duration was significantly longer in the Mendelsohn maneuver than in other tasks. Effortful swallow was most effective in increasing tongue pressure. The integrated value of tongue pressure at the posterior-circumferential parts in the Mendelsohn maneuver and at the median parts in the effortful swallow showed a tendency to increase. These results suggest that tongue pressure increases along a wide part of the hard palate in effortful swallow because the anchor of tongue movement is emphasized at the anterior part of the hard palate. The Mendelsohn maneuver provides prolonged and accentuated tongue-palate contact at the posterior-circumferential parts, which might be important for hyoid-laryngeal elevation during swallowing.