Effortful Swallow Research Articles

Effect of the combination of Mendelsohn maneuver and effortful swallowing on aspiration in patients with dysphagia after stroke.

[Purpose] This study investigated the effect of a combined method incorporating the Mendelsohn maneuver and effortful swallowing on aspiration in patients with dysphagia after stroke. [Subjects and Methods] Three patients with dysphagia were recruited. All patients were treated with a combined method consisting of the Mendelsohn maneuver and effortful swallowing. The intervention period was total 20 sessions. Evaluation was based on videofluoroscopic swallowing study and the degree of aspiration was assessed using penetration-aspiration scale. [Results] Before and after intervention, all participants showed a decrease in aspiration with liquid type and semisolid type food. [Conclusion] This study confirms that the combined method of the Mendelsohn maneuver and effortful swallowing has a positive effect on aspiration in patients with dysphagia after stroke.

Effects of bedside self-exercise on oropharyngeal swallowing function in stroke patients with dysphagia: a pilot study.

[Purpose] The purpose of this study was to investigate the effect of self-exercise on oropharyngeal swallowing function in patients with dysphagia. [Subjects and Methods] Nine patients with dysphagia after stroke were recruited. Self-exercise including effortful swallowing, tongue strengthening, and shaker exercise was performed 5 times a week for 4 weeks. Swallowing function was evaluated using the videofluoroscopic dysphagia scale (VDS) based on a videofluoroscopic swallowing study. [Results] There were significant differences in both the oral and pharyngeal phases of the VDS before and after the intervention. [Conclusion] This study demonstrated that bedside self-exercise is a positive method to improve oropharyngeal swallowing function in patients with dysphagia after stroke.

혀-입천장을 강조한 노력삼킴과 억제한 노력삼킴 간의 목뿔위, 목뿔아래, 깨물근 활성 비교

혀-입천장을 강조한 노력삼킴과 억제한 노력삼킴 간의 목뿔위, 목뿔아래, 깨물근 활성 비교

Impact of Swallowing on Doses Delivered to Spinal Cord in Cervical Spine Radiosurgery—Dynamic Volume Helical Shuttle Imaging Analysis

Spinal cord displacement happens when ever patient swallows in treatment position for head and neck cancers. Because of momentary breath hold during swallowing 4-D imaging is not ideal as it leads to sorting errors and image artifacts. Dynamic volume Helical shuttle (DVHS) imaging is continuous bidirectional scan with extended Z coverage, which enables us to delineate structures properly without any artifacts. The present study aims at evaluating the subtle dose deformations of spinal cord consequent to swallowing for patients undergoing cervical spine radiosurgery. Forty-two cervical spine metastases following rigid immobilization with S-Board underwent thin slice CT imaging on 128 slice CT scanner and post-contrast myelographic MR imaging (Axial T2 FSE, FS, and CISS sequence). With regards to CT imaging, all patients underwent a 10 second static CT scan (no swallowing) and 3 mts - DVHS imaging (with effortful swallowing). For DVHS, image data for single patient was acquired during voluntary effortful swallowing act (once in 20 sec) at 2 alternating table positions with the table shuttling back and forth. Nearly 2,000 images/per pt. were reformatted using Dynamic Pitch Cone Beam Reconstruction for 15 passes @ 2.5 mm thickness and cine looped to quantify the range of motion. Following target and thecal sac localization on fused CT-MR scan, a median dose of 18 Gy was planned using single VMAT arc on static scan dataset, which is then deformably dose warped on the extreme passes of DVHS deglutition dataset. The registration accuracy was quality assured using reg-refine and reg-reveal tools using alignment locks. Deglutition-induced GTV and Spinal cord displacements were quantified based on position change during deglutition relative to pre-swallow structure location in S-I, A-P, and lateral directions. The dose variations consequent to deglutition were analyzed and changes greater than 0.5 Gy reported as percent change (normalized to prescription dose) were considered potentially significant. Deglutition-induced maximal PTV displacements ranged from 2 mm to 5 mm with mean and standard deviation of 1.5 +/- 2, 1.70 +/- 1.51, 2.25 +/- 1.2, and 2.2 +/- 1.7 mm in the A, P, I, and S directions, respectively. The SC displacement ranged from 2.8 mm +/- 0.1 mm, 2.2 mm +/- 1.4 mm in A-P direction. Upon dosimetric analysis on extreme passes of DVHS dataset 35 of 42 patients showed that 96% of the prescribed dose would still be delivered to the tumor even if the tumor partly vacated the PTV during the act of swallowing. For the remaining 7 patients (frequent swallowers), the target coverage reached to around 92%. For non-spinous process target, a 2 mm shift increased thecal dose up to 100 cGy. The median accumulated doses delivered in spinal cord were high in frequent swallowers. This is the first study reported in literature using DHVS to analyze motion in cervical spine radiosurgery. FFF technology with actual BOT around 2 mts would be preferred as it mitigates impact of swallowing on dose deformations.

A Pilot Study of the Head Extension Swallowing Exercise: New Method for Strengthening Swallowing-Related Muscle Activity.

This pilot study examined the effect of a new head extension swallowing exercise (HESE) on submental muscle activity and tongue strength in healthy volunteers. Fifteen young adults (10 females and 5 males) were instructed to extend their head backwards as much as possible, and while watching the ceiling, swallowed their saliva every 10s for a duration of 20min. Twenty-four treatments were performed over 8weeks. The outcome variables evaluated at baseline, 4 and 8weeks of training, and 12-week follow-up included mean and peak submental muscle activation amplitudes during normal and effortful swallowing measured via surface electromyography, and anterior and posterior isometric tongue pressures were measured with the Iowa Oral Performance Instrument. Results indicated that the muscle activation amplitudes during effortful swallowing increased significantly at 4 and 8weeks compared to baseline (p<0.025). However, the increases in amplitudes during normal swallowing were minor (nonsignificant) after 8weeks compared to baseline. The isometric pressures of the tongue tip and the posterior part of the oral tongue were significantly higher at 8weeks compared to baseline (p<0.025). Thus, the 8-week HESE protocol significantly improved suprahyoid muscle activity during effortful swallowing as well as the isometric tongue pressures. The HESE appears effective in exercising and strengthening the suprahyoid muscles and tongue muscles in healthy participants. Although encouraging, these results need to be replicated in clinical trials for testing the therapeutic effects of the HESE in older adults and patients with dysphagia who present with decreased hyolaryngeal elevation.

Effects of tongue pressing effortful swallow in older healthy individuals

IntroductionThe risk of swallowing disorders is increased for older individuals due to weak tongue and pharyngeal muscle strength. This study was appraised the value of a preventative approach by developing the tongue pressing effortful swallow (TPES) applied using a home-based and self-administered procedure. The TPES was developed by combining two swallowing exercises: tongue strengthening exercise and the effortful swallow. The purpose of this study was to examine the effects of the TPES on maximum tongue pressure and peak amplitude of submental muscle activity in older individuals. Material and methods27 older individuals (mean 73 years) performed a 4-week TPES. The exercise program was adapted to a home-based and self-administered procedure. The maximum tongue pressure was measured by the Iowa Oral Performance Instrument and peak amplitude of submental muscle activity by surface electromyography (sEMG). Statistical comparisons were made by a matched pairs t-test (p<0.05). ResultsThe results of this study showed that the TPES had statistically significant and positive effects on increasing maximum tongue pressure, but the peak amplitude of the submental sEMG did not differ between before and after exercises. ConclusionsThe TPES had a positive impact in older individuals. The TPES, a combining exercise, was possible because two exercises had common physiological events. The TPES was a more innovative and efficient approach than the tongue strengthening exercise alone. In addition, older individuals were able to perform the swallowing exercise at home and by themselves with little assistance. Future research needs to refine the TPES and apply it to patients with dysphagia.

Effects of neuromuscular electrical stimulation combined with effortful swallowing on post‐stroke oropharyngeal dysphagia: a randomised controlled trial

Neuromuscular electrical stimulation (NMES) has been used as a therapeutic intervention for dysphagia. However, the therapeutic effects of NMES lack supporting evidence. In recent years, NMES combined with traditional swallowing therapy has been used to improve functional recovery in patients with post-stroke dysphagia. This study aimed to investigate the effects of effortful swallowing combined with neuromuscular electrical stimulation on hyoid bone movement and swallowing function in stroke patients. Fifty stroke patients with mild dysphagia who were able to swallow against the resistance applied by using NMES and cooperate actively in training were included. This study was designed as a 6-week single-blind, randomised, controlled study. In the experimental group, two pairs of electrodes were placed horizontally in the infrahyoid region to depress the hyoid bone. The NMES intensity was increased gradually until the participants felt a grabbing sensation in their neck and performed an effortful swallow during the stimulation. In the placebo group, the same procedure was followed except for the intensity, which was increased gradually until the participants felt an electrical sensation. All participants underwent this intervention for 30 min per session, 5 sessions per week, for 6 weeks. Videofluoroscopic swallowing studies (VFSS) were carried out before and after the intervention and kinematics of the hyoid bone and swallowing function were analysed based on the VFSS. The experimental group revealed a significant increase in anterior and superior hyoid bone movement and the pharyngeal phase of the swallowing function. This intervention can be used as a novel remedial approach in dysphagic stroke patients.

A Pilot Study of the Tongue Pull-Back Exercise for Improving Tongue-Base Retraction and Two Novel Methods to Add Resistance to the Tongue Pull-Back.

This pilot study investigated the tongue pull-back (TPB) exercise to improve tongue-base retraction as well as two methods to add resistance to the TPB. Surface electromyography (sEMG) to the submental triangle was used as an indication of tongue-base activity on 13 healthy adults during: (1) saliva swallow, (2) 15mL water swallow, (3) effortful swallow, (4) unassisted TPB, (5) TPB with added resistance by holding the tongue with gauze (finger-resisted TPB), and (6) TPB with the tongue clipped to a spring-loaded tension resistance device (device-resisted TPB). Order of the exercises was randomized. The exercises fell into two groups-weak and intense. Weak exercises included saliva swallow, water swallow, and unassisted TPB (mean sEMG=19.07μV, p=.593). Intense exercises included effortful swallow, finger-resisted TPB, and device-resisted TPB (mean sEMG=36.44μV, p=.315). Each intense exercise resulted in significantly higher mean sEMG peak amplitude than each weak exercise (p<.05), with one exception; the effortful swallow was not significantly different than the unassisted TPB (p=.171). This study provides preliminary evidence that the unassisted TPB may not be any more helpful for improving tongue-base retraction than normal swallowing. Adding resistance to the TPB by holding the tongue with gauze may be an effective alternative. This study also demonstrates proof-of-concept for creating a device to attach to the tongue and provide tension resistance during the TPB exercise. Further research with a more sophisticated design is needed before such a device can be fully developed and implemented clinically.

Pressure topography metrics for high-resolution pharyngeal-esophageal manofluorography-a normative study of younger and older adults.

We aimed to define normative values for novel pressure topography metrics for high-resolution pharyngeal-esophageal manofluorography. The effects of age, gender, and bolus properties were examined. Concurrent high-resolution manometry (HRM) and videofluoroscopy data were collected from 22 younger (aged 21-40) and 22 older (aged 60-80) healthy subjects. Pressure topography was analyzed by correlating pressure domains with videofluoroscopic events. Nine pressure topography metrics of the pharyngeal and proximal esophageal swallow were extracted; four of these were also compared with previously obtained esophageal HRM studies to assess the effects of catheter diameter. Older individuals exhibited more vigorous contractility in the pharynx than did younger subjects with all bolus types, but the greatest values for both groups were with effortful swallow and on that measure the age groups were similar. Upper esophageal sphincter (UES) intrabolus pressure during sphincter opening was also greater in the older subjects. Some gender differences were observed, particularly related to proximal esophageal contractile vigor. Bolus consistency had no consistent effect. Studies using the larger catheter diameter resulted in significantly greater contractile vigor in the UES and proximal esophagus. Older adults exhibited more vigorous pharyngeal contractions than young adults, albeit within a similar range of capacity, perhaps reflecting a compensatory response to other age-related physiological changes. Greater UES intrabolus pressures observed during bolus transit in the older group likely reflect reduced UES compliance with age. Normative data on novel HRM metrics collected in this study can serve as a reference for future clinical studies.

Effects of Effortful Swallow on Cardiac Autonomic Regulation.

Swallowing-induced changes in heart rate have been recently reported. However, it is not apparent the responses of heart rate variability (HRV) elicited by effortful swallow maneuver. We investigated the acute effects of effortful swallowing maneuver on HRV. This study was performed on 34 healthy women between 18 and 35years old. We assessed heart rate variability in the time (SDNN, RMSSD, and pNN50) and frequency (HF, LF, and LF/HF ratio) domains and, visual analysis through the Poincaré plot. The subjects remained at rest for 5min during spontaneous swallowing and then performed effortful swallowing for 5min. HRV was analyzed during spontaneous and effortful swallowing. We found no significant differences for SDNN, pNN50, RMSSD, HF in absolute units (ms(2)). There is a trend for increase of LF in absolute (p=0.05) and normalized (p=0.08) units during effortful swallowing. HF in normalized units reduced (p=0.02) during effortful swallowing and LF/HF ratio (p=0.03) increased during effortful swallowing. In conclusion effortful swallow maneuver in healthy women increased sympathetic cardiac modulation, indicating a cardiac overload.

Effortful swallow enhances vertical hyolaryngeal movement and prolongs duration after maximal excursion.

Effortful swallowing (EFS) is a common compensatory swallowing manoeuver for dysphagia patients. We investigated the influence of EFS on temporal and spatial characteristics of the movements of the hyoid bone, larynx and epiglottis in healthy subjects. A total of 41 volunteers swallowed 10 mL of diluted barium solution using two swallowing strategies: usual and effortful swallowing (USS and EFS). The motions of the hyoid bone, larynx and epiglottis were tracked using frame-by-frame kinematic motion analysis of videofluoroscopic images. Maximal velocities and maximal displacements of hyoid and larynx, the maximal angle of the epiglottic tilt, and the durations of hyoid excursion, laryngeal elevation and epiglottic tilt were measured. Compared to USS, EFS was associated with significantly greater vertical displacement of the hyoid (P < 0.001), vertical and horizontal displacement of the larynx (P = 0.003, P = 0.019), and maximal angle of the epiglottic tilt (P = 0.001). In addition, the durations of the vertical and horizontal excursions of the hyoid, vertical excursion of the larynx and the epiglottic tilt were greater in EFS, compared with USS. Effortful swallowing was also associated with significantly greater maximum velocities of the hyoid and larynx during swallowing. In conclusion, the EFS manoeuver facilitates vertical speed and distance of hyolaryngeal excursion and epiglottic tilt and extends the duration of excursion and the epiglottic tilt, especially after reaching maximal excursion in healthy subjects. These results confirm the temporal and kinematic benefits of airway protection induced by the EFS manoeuver.

Effects of Tongue Strength Training and Detraining on Tongue Pressures in Healthy Adults.

This study examined the effect of tongue strengthening training and long-term detraining on tongue tip pressure, tongue base pressure, and tongue pressure during effortful swallowing. Ten young healthy volunteers (21-35 years) were participated in this study. Participants received 8-week tongue strengthening exercise 3 days a week with each session lasting 30 min. Measurement of tongue pressure and tongue strengthening exercise were administrated using Iowa Oral Performance Instrument (IOPI). Training intensity was applied at 60 and 80% of maximal tongue pressure for the first week and the remainder, respectively. Following completion of 8-week training, 28 weeks of detraining period was continued. Training increased tongue tip pressure, tongue base pressure, and tongue pressure during effortful swallowing above pre-training values (p < 0.05). After 28-week detraining, all tongue variables were significantly lower than after 8-week training (p < 0.05) but remained significantly higher than pre-training levels (p < 0.05). These findings demonstrate that high-intensity tongue strengthening exercise can improve tongue pressures. However, training effects were diminished gradually during detraining period. Thus, maintenance programs after strengthening exercise would be required for prolonging training effects.

Immediate effects of transcutaneous electrical stimulation on physiological swallowing effort in older versus young adults.

This study compared the immediate impact of different transcutaneous electrical stimulation (TES) amplitudes on physiological swallowing effort in healthy older adults versus young adults. Swallowing physiology changes with age. Reduced physiological swallowing effort in older adults including lower lingua-palatal and pharyngeal pressures may increase risk for swallowing dysfunction (i.e. dysphagia). Transcutaneous electrical stimulation (TES) has been advocated as an adjunctive modality to enhance outcomes in exercise-based therapy for individuals with dysphagia. However, significant variation in how TES is applied during therapy remains and the physiological swallowing response to TES is poorly studied, especially in older adults. Physiological change in swallowing associated with no stimulation, sensory stimulation and motor stimulation was compared in 20 young adults versus 14 older adults. Lingua-palatal and pharyngeal manometric pressures assessed physiological swallowing effort. Multivariate analyses identified interactions between age and stimulation amplitude on lingual and pharyngeal functions. Motor stimulation reduced anterior tongue pressure in both age groups but selectively reduced posterior lingua-palatal pressures in young adults only. Sensory stimulation increased base of tongue (BOT) pressures in older adults but decreased BOT pressures in young adults. Motor stimulation increased hypopharyngeal pressures in both groups. Age and TES level interact in determining immediate physiological responses on swallow performance. A one-size-fit-all approach to TES in dysphagia rehabilitation may be misdirected.

Dysphagia Management in Acute and Sub-acute Stroke.

Swallowing dysfunction is common after stroke. More than 50% of the 665 thousand stroke survivors will experience dysphagia acutely of which approximately 80 thousand will experience persistent dysphagia at 6 months. The physiologic impairments that result in post-stroke dysphagia are varied. This review focuses primarily on well-established dysphagia treatments in the context of the physiologic impairments they treat. Traditional dysphagia therapies including volume and texture modifications, strategies such as chin tuck, head tilt, head turn, effortful swallow, supraglottic swallow, super-supraglottic swallow, Mendelsohn maneuver and exercises such as the Shaker exercise and Masako (tongue hold) maneuver are discussed. Other more recent treatment interventions are discussed in the context of the evidence available.

Effects of Effortful Swallow on Esophageal Function in Patients with Presumed Esophageal Motility Disorders

Objectives: (1) Describe the changes in esophageal amplitude and swallow duration during an effortful swallow in patients with esophageal pathology. (2) Understand the utility of the effortful swallow in rehabilitation of esophageal dysmotility disorders. Methods: Prospective case control study in which 10 patients referred for esophageal manometry were enrolled. Each participant performed 20 swallow trials (10 effortful and 10 normal) where amplitude and duration of swallow were measured at 4 different sensors (1 striated, 1 mixed, and 2 smooth muscle sites). The effects of the swallow condition (effortful vs noneffortful), sensor site, and sex on esophageal peak pressure and swallow duration were examined. Results: The study included 10 participants (8 females, 2 males). There were several patients in whom the effortful swallow showed a statistically significant increase in peak swallow pressure or duration of the measured swallow at a particular sensor. This was not consistent across all patients nor across a particular sensor. There were more statistically significant changes in males compared with females. Conclusions: Despite clear evidence in previous studies demonstrating that volitional manipulation of the oropharyngeal phase of swallowing affects esophageal physiology in healthy individuals, a small study of patients with esophageal pathology is unable to demonstrate similar results. In future studies, we will aim to include a greater number of patients with diagnosed esophageal dysmotility.

노인요양시설 뇌졸중 노인을 위한 운동중심 연하훈련 프로그램의 효과

Purpose: The purpose of this study was to develop a training program for swallowing and to test its effect on swallowing capacity and nutritional status among nursing home residents with stroke. Methods: A swallowing training program was developed by literature review, expert validation and a pilot test. A pretest and posttest quasi-experimental study design with nonequivalent control group was used to evaluate the effectiveness of the program. Swallowing training was conducted for thirty minutes, three times a week for 8 weeks. Swallowing capacity including dysphagia screening score, swallowing symptom questionnaire and tongue pressure, and nutritional status including body mass index and mid arm muscle circumference were measured at the baseline and at 8 weeks. Results: The exercised-based swallowing training program consisted of oromotor exercise, expiratory muscle strength exercise and effortful swallow. The participants were 77.2 years old on average. At the completion of 8-week program, the experimental group showed better scores in dysphagia screening (p=.039) and swallowing symptom questionnaire (p=.004) and a significant increase in tongue pressure (p=.003). Conclusion: The exercised-based swallowing training program was safely applied to nursing home residents with stroke and showed a significant improvement of swallowing capacity. Further studies are needed to identify its effect on the nutritional status.

Pharyngeal transit in patients with chronic progressive external ophthalmoplegia

Purpose: A common presentation of mitochondrial myopathies is chronic progressive external ophthalmoplegia (CPEO). Dysphagia is a complaint in about 50% of cases.Method: This investigation evaluated pharyngeal transit in patients with CPEO. Videofluoroscopic swallowing evaluation was performed with paste, liquid and solid boluses in 14 patients with CPEO and in 16 normal volunteers.Result: There was no difference between patients and volunteers in the duration of pharyngeal swallowing events with the liquid bolus. Compared to control participants, patients with CPEO had significantly shorter duration of pharyngeal transit for paste and solid boluses, of pharyngeal clearance for paste bolus, and of upper oesophageal sphincter transit for paste and solid boluses. Spontaneous multiple swallows and effortful swallows were performed by patients but not by the volunteers.Conclusion: It was concluded that patients with CPEO have shorter pharyngeal transit duration of paste and solid boluses than normal volunteers, which may be a consequence of a spontaneous smaller bolus volume in each swallow and/or effortful swallows.

Normative data for pharyngeal pressure generation during saliva, bolus, and effortful saliva swallowing across age and gender

Pharyngeal manometry provides information on both temporal and amplitude aspects of pressure generation during swallowing. This report provides normative data for three channel pharyngeal manometry on these parameters of pressure generation, providing the normal range of swallowing pressure against which impaired swallowing pressures can be compared. Participants were equally divided into four groups according to age and sex: young females (n = 20), young males (n = 20), older females (n = 20), and older males (n = 20). A discrete-sensor 3-channel manometric catheter measured pharyngeal pressure during three swallowing conditions: saliva swallowing, 10 ml bolus swallowing, and effortful saliva swallowing. Amplitude of peak pressure (mmHg) was recorded for each sensor during the swallow. The latency (ms) between peak pressure at Sensor 1 (approximately BOT) and Sensor 2 (approximately laryngeal additus) and total duration of upper esophageal sphincter relaxation were recorded. Additionally, a pharyngeal composite measure, consisting of an average of the peak amplitude of the two sensors in the pharyngeal segment, was generated to compensate for potential imprecision in recording due to intra-swallow catheter movement. Statistical analyses included derivation of means and 95% confidence intervals across swallowing conditions and participant groups. Clinically, these data provide a comparative database for identification of pathologic pharyngeal functioning in patients with swallowing impairment, and may aid in future studies of swallowing biomechanics.

Magnetic resonance imaging of the effortful swallow.

The effortful swallow was designed to improve posterior mobility of the tongue base and increase intraoral pressures. We characterized the effects of this maneuver via dynamic magnetic resonance imaging (dMRI) in healthy patients. A 3-T scanner was used to obtain dMRI images of patients swallowing pudding using normal as well as effortful swallows. Ninety sequential images were acquired at the level of the oropharynx in the axial plane for each swallow; 3 series were obtained for each swallow type for each patient. Images were acquired every 113 ms during swallowing. The images were analyzed with respect to oropharyngeal closure duration, anteroposterior and transverse distance between the oropharyngeal walls, and oropharyngeal area before and after closure. Preswallow reduced pharyngeal area was observed (P = .02; mean = 212.61 mm² for effortful, mean = 261.92 mm² for normal) as well as prolonged pharyngeal closure during the swallow (P < .0001; mean = 742.18 ms for effortful, mean = 437.31 ms for normal). No other differences were noted between swallow types. Interrater and intrarater reliability of all measurements was excellent. This preliminary investigation is the first to evaluate the effects of effortful swallows via dMRI. In our cohort, consistent physiologic changes were elicited, consistent with clinical dogma regarding this maneuver.

Tu2004 Therapy of Zenker's Diverticulum With Flexible Endoscopy Versus a Rigid Endoscopic Approach: a Matched Cohort Study

Introduction The effortful swallow (ES) is designed to increase tongue base to posterior wall contact in patients with reduced oropharyngeal pressure, hereby improving bolus clearance. However, the effect of bolus volume and consistency on swallowing during this maneuver is unclear. Hence, we aim to quantify the effect of ES on pressure flow metrics and its interaction with bolus volume and consistency in healthy subjects. Material and Methods 12 healthy controls (6M, 6F, mean age 32 years, 21-53 years) swallowed 3 bolus consistencies (liquid, semisolid, and solid) in 2 bolus volumes (small [5ml-2cm2] or large [10ml-4cm2]). All swallows were recorded with combined high resolution manometryimpedance (36P12Z catheter) and analyzed using AIMplot software, deriving swallowmetrics for the pharynx and upper esophageal sphincter (UES). Different mixed models were estimated with each AIM metric as dependent variable, and volume, consistency and head posture as within-subject independent variables. Pairwise differences were tested using posthoc t-tests corrected for multiple comparisons. Results No significant effect of ES on pharyngeal peak pressure was found (p=0.4) (Figure 1). ES significantly increased time from nadir impedance to pharyngeal peak pressure (p<0.0001) (Figure 2), indicating improved bolus propulsion compared to the head neutral position. Discussion This study shows that ES does not increase the strength of the pharyngeal contraction, but rather influences its timing with bolus flow. We believe this observation may be clinically relevant as ES is often the maneuver of choice in patients with pharyngeal hypocontractility. Our finding may contribute to the understanding of inconsistent treatment success while using this swallow maneuver.