Liquid Swallows Research Articles

Relevance of ineffective esophageal motility to striated esophageal muscle contraction: Studies with high-resolution manometry.

Striated esophageal muscle contraction (SEC) is important for pharyngeal swallowing and deglutition augmentation against aspiration. Its clinical relevance is unclear in patients with ineffective esophageal motility (IEM). In this study, we aimed to characterize and compare SEC in consecutive patients with and without IEM. All eligible patients were evaluated for SEC, primary and secondary peristalsis using high-resolution manometry (HRM) with one mid-esophageal injection port. Primary peristalsis was assessed with 10 5-mL liquid swallows and multiple rapid swallows (MRS), while secondary peristalsis was performed with rapid air injections of 20 mL. All peristatic parameters of HRM were measured, and SEC and its contractile integral (SECI) were evaluated. One hundred and forty patients (59.3% women, mean age 46.1 ± 13.1 years) were included. There was no difference in SECI between patients with and without IEM (p = 0.91). SECI was also similar between patients with and without secondary peristalsis for IEM (p = 0.63) or normal motility (p = 0.80). No difference in SECI was seen between patients with and without MRS for IEM (p = 0.55) or normal motility (p = 0.88). SECI was significantly higher in male patients than female patients in IEM patients (p = 0.01). SECI significantly correlated with age in patients with normal motility (r = -0.31, p = 0.01). Aging may have a negative impact on SEC in patients with normal motility, while gender difference in SECI occurs in IEM patients. Neither secondary peristalsis nor MRS influences SECI.

Association between swallowing dynamics, tongue pressure and pulmonary function in patients with idiopathic pulmonary fibrosis

BackgroundSwallowing is a complex process that requires the coordination of muscles in the mouth, pharynx, larynx, and esophagus. Dysphagia occurs when a person has difficulty swallowing. In the case of subjects with respiratory diseases, the presence of oropharyngeal dysphagia potentially increases lung disease exacerbations, which can lead to a rapid decline in lung function. This study aimed to analyze the swallowing of patients with idiopathic pulmonary fibrosis (IPF).MethodsPatients with IPF were evaluated using the Eating Assessment Tool (EAT-10), tongue pressure, the Timed Water Swallow Test (TWST), and the Test of Mastication and Swallowing Solids (TOMASS). The findings were related to dyspnea severity assessed by the modified Medical Research Counsil (mMRC) score; the nutritional status screened with Mini Nutritional Assessment (MNA) tool; and pulmonary function tests, specifically spirometry and measurement of the diffusing capacity for carbon monoxide (DLCO), the maximal inspiratory pressure (PImax), and the maximal expiratory pressure (PEmax).ResultsThe sample consisted of 34 individuals with IPF. Those who exhibited swallowing modifications scored lower on the MNA than those who did not (9.6 ± 0.76 vs. 11.64 ± 0.41 points; mean difference 1.98 ± 0.81 points; p = 0.02). They also showed poorer lung function when considering the predicted force vital capacity (FVC; 81.5% ± 4.61% vs. 61.87% ± 8.48%; mean difference 19.63% ± 9.02%; p = 0.03). The speed of liquid swallowing was altered in 31of 34 of the evaluated subjects (91.1%). The number of liquid swallows correlated significantly with the forced expiratory volume in 1 s (FEV1)/FVC ratio (r = 0.3; p = 0.02). Solid eating and swallowing assessed with the TOMASS score correlated with lung function. The number of chewing cycles correlated negatively with PImax% predicted (r = -0.4; p = 0.0008) and PEmax% predicted (r = -0.3; p = 0.02). FVC% predicted correlated with increased solid swallowing time (r = -0.3; p = 0.02; power = 0.6). Swallowing solids was also impacted by dyspnea.ConclusionPatients with mild-to-moderate IPF can present feeding adaptations, which can be related to the nutritional status, lung function, and the severity of dyspnea.

Esophago-gastric junction findings on high resolution impedance manometry in children with esophageal atresia.

Using high resolution impedance manometry (HRIM), this study characterized the esophago-gastric junction (EGJ) dynamics in children with esophageal atresia (EA). Esophageal HRIM was performed in patients with EA aged less than 18 years. Objective motility patterns were analyzed, and EGJ data reported. Controls were pediatric patients without EA undergoing investigations for consideration of fundoplication surgery. Seventy-five patients (M:F = 43:32, median age 1 year 3 months [3 months-17 years 4 months]) completed 133 HRIM studies. The majority (64/75, 85.3%) had EA with distal tracheo-esophageal fistula. Compared with controls, liquid swallows were poorer in patients with EA, as evident by significant differences in distension pressure emptying and bolus flow time (BFT). The integrated relaxation pressure for thin liquid swallows was significantly different between EA types, as well as when comparing patients with EA with and without previous esophageal dilatations. The BFT for solid swallows was significantly different when compared with EA types. We have utilized HRIM in patients with EA to demonstrate abnormalities in their long-term EGJ function. These abnormalities correlate with poorer esophageal compliance and reduced esophageal peristalsis across the EGJ. Understanding the EGJ function in patients with EA will allow us to tailor long-term management to specific patients.

Sliced Jelly Whole Swallowing Reduces Deglutition Risk: A Novel Feeding Method for Patients with Dysphagia.

Texture modification in the form of gels or jellies is used for patients with dysphagia. For over 20 years, our group has been using gelatin jellies, a type of gel, as a starting diet for patients with dysphagia. Gelatin jellies are served in a small-sliced form and swallowed whole. In sliced jelly whole swallowing (SJWS), sliced gelatin jelly (SGJ) passes through the pharynx in one lump without collapsing. This study aimed to examine the usefulness of SJWS. We analyzed the images of videofluoroscopic swallowing studies performed using the normalized residue ratio scale (NRRSv: vallecula, NRRSp: pyriform sinus), the penetration-aspiration scale (PAS), and pharyngeal transit time (PTT) in 50 patients with dysphagia and compared the results in a prospective study. SJWS had significantly less residue in both NRRSv and NRRSp than in moderately thickened liquid swallowing. No significant differences in PAS scores were found between SGJ and moderately thickened liquid. Additionally, no significant differences in PTT scores were noted between the two. This study demonstrated the usefulness of SJWS in improving swallowing safety in patients with dysphagia. Further studies are needed to evaluate the reproducibility of the test, the comparison of SGJ with other thickened liquids, and the safety of SJWS for different diseases.

Dysphagia in Open Partial Horizontal Laryngectomy Type IIa: Quantitative Analysis of Videofluoroscopy using the ASPEKT Method.

Open Partial Horizontal Laryngectomy (OPHL) Type IIa surgery is a conservative surgical technique used in the treatment of laryngeal carcinomas. In this pilot study, we aimed to characterize swallowing function and physiology in a series of patients after OPHL Type IIa surgery through comparison to healthy reference values for quantitative measures for videofluoroscopy. We performed retrospective quantitative analysis of videofluoroscopy recordings of thin liquid swallows for a preliminary sample of 10 male patients. Each videofluoroscopy clip was rated in triplicate by trained blinded raters according to the ASPEKT Method (Analysis of Swallowing Physiology: Events, Kinematics and Timing). This preliminary sample of patients with previous OPHL surgery showed functional airway protection, with only 2 patients showing incomplete laryngeal vestibule closure (LVC) and associated airway invasion. However, the majority of patients (90%) showed prolonged latencies to LVC and upper esophageal sphincter (UES) opening. Prolonged durations of LVC and UES opening were also noted, but these were in the direction of compensation rather than impairment. Reduced pharyngeal area at rest was seen in 70% of the sample, and all patients showed poor pharyngeal constriction. Post-swallow residue was a prominent finding in ≥ 75% of these patients. In particular, reduced or absent constriction of the hypopharynx in the region of the pyriform sinuses was noted as a characteristic of swallowing in this sample. The data from these patients suggest that despite functional airway protection, severe swallowing dysfunction involving poor pharyngeal constriction and bolus clearance may be likely after OPHL surgery.

Dysphagia Pattern in Early to Moderate Parkinson's Disease Caused by Abnormal Pharyngeal Kinematic Function.

Airway invasion is common in patients with Parkinson's disease (PD) and can cause serious complications. However, a PD-related dysphagic pattern has not been clearly elucidated. In this study, 53 patients with early to moderate PD were enrolled to undergo a videofluoroscopic study of swallowing evaluation (VFSS) and a battery of neuropsychological assessments. A set of VFSS variables (three visuoperceptual, nine temporal, and six spatial) were measured. The main effects of bolus viscosity and volume on airway invasion were calculated. Statistical analyses were performed to determine key kinematic factors of airway invasion for swallowing each bolus type. Airway invasion frequency was significantly higher for liquid boluses (liquid vs. pudding P < 0.001; liquid vs. honey P = 0.006). Laryngeal vestibule closure reaction time (LVCrt) was the key kinematic factor of airway invasion for 3ml liquid swallow (P = 0.040), anterior displacement of hyoid bone was the key kinematic factor for both 5ml and 10ml liquid swallows (P = 0.010, 0.034, respectively). Male sex and advanced Hoehn and Yahr stage were significantly related to reduced anterior displacement of hyoid bone. These results reveal the dysphagic pattern related to PD, demonstrating that prolonged LVCrt and reduced anterior displacement of hyoid bone are two crucial kinematic factors contributing to airway invasion during the liquid swallow. In addition, hyoid bone dysfunction was correlated with disease severity and male sex. Our findings warrant further investigation of the pathophysiological mechanism of dysphagia in PD and would guide clinical intervention.

Normative High-Resolution Pharyngeal Manometry: Impact of Age, Size of System, and Sex on Primary Metrics and Pressure Stability.

There have been many reports of normative pharyngeal swallowing pressures using high-resolution pharyngeal manometry, but there is a fair amount of between-subject variance in reported pressure parameters. The purpose of this study was to put forward normative pharyngeal high-resolution manometry measures across the lifespan and investigate the effects of age, size of system, and sex. High-resolution pharyngeal manometry was performed on 98 healthy adults (43 males) between the ages 21 and 89. Pressure duration, maxima, integral, and within-individual variability metrics were averaged over 10 swallows of 10-ml thin liquid. Multiple linear and logistic regressions with model fitting were used to examine how pharyngeal pressures relate to age, pharyngeal size, and sex. Age was associated with tongue base maximum pressure, tongue base maximum variability, and upper esophageal sphincter-integrated relaxation pressure (F3,92 = 6.69; p < 0.001; adjusted R2 = 0.15). Pharyngeal area during bolus hold was associated with velopharynx integral (F1,89 = 5.362; p = 0.02; adjusted R2 = 0.05), and there was no significant model relating pharyngeal pressures to C2-C4 length (p < 0.05). Sex differences were best described by tongue base integral and hypopharynx maximum variability (χ2 = 10.27; p = 0.006; pseudo R2 = 0.14). Normative data reveal the distribution of swallow pressure metrics which need to be accounted for when addressing dysphagia patients, the importance of pressure interactions in normal swallow, and address the relative stability of swallow metrics with normal aging.

Delineation of the healthy rabbit tongue by immunohistochemistry – A technical note

In the oral cavity the tongue is an important muscular organ that supports the swallowing of food and liquids. It is responsible for the sense of taste, based on the many different taste buds it contains. Research in the field of tongue diseases demands for suitable preclinical models. The healthy rabbit tongue may therefore serve as baseline and reference for the pathological situation. With this consideration, we covered the fixation and histological stainings as well as the immunohistochemical labelling of the healthy rabbit tongue. In this technical note, initial choice of the fixative is discussed, with a comparison of formalin fixation and subsequent paraffin embedding versus cryopreservation. Moreover, we delineate the effect of an antigen retrieval step for formalin fixation by several examples. Finally, we provide ECM markers collagen I, collagen III, fibronectin, α-SMA and elastin staining as well as ki67 for proliferative status and PAR-2 protein expression as a marker for inflammatory status and nociception in tongue sections, mainly from the tongue body. Technically, we found superiority of paraffin sections for collagen I, collagen III, fibronectin, ki67 and α-SMA labelling, for selected detections systems. As for ECM components, the lamina propria was very rich in collagen and fibronectin, while the muscular body of the tongue showed only collagen and fibronectin positive areas between the muscle fibers. Moreover, α-SMA was clearly expressed in the walls of arteries and veins. The inflammatory marker PAR-2 on the other hand was prominently expressed in the salivary glands and to some extent in the walls of the vessels. Particular PAR-2 expression was found in the excretory ducts of the tongue. This technical note has the aim to provide baseline images that can be used to compare the pathological state of the diseased rabbit tongue as well as for inter-species comparison, such as mouse or rat tongue. Finally, it can be used for the comparison with the human situation.

Normal Variations in Upper Esophageal Sphincter Function During Deglutition: A Secondary Analysis of Videofluoroscopic Data.

Cricopharyngeal dysfunction is a common potential cause of pharyngoesophageal dysphagia. Contextual factors (i.e., personal demographics and bolus properties) appear to impact upper esophageal sphincter (UES) function but have yet to be assessed collectively in a large-scale study using psychometrically sound swallow task procedures. Using a standardized and validated videofluoroscopic approach, we investigated the collective effects of age, sex, and swallow task on UES opening duration (UESOdur) and UES maximum distension (UESmax) in a large sample of healthy adults. UESOdur and UESmax data were analyzed from existing videofluoroscopic images of 195 healthy adults (21-89 years old) across seven swallow tasks (thin liquid to viscous liquids, puree, and a solid). Generalized estimating equation modeling captured the effects of the aforementioned contextual factors (α = 0.05). UESOdur significantly increased with age, while UESmax had an inverse relationship. Females had significantly wider UESmax. UESOdur of 5 mL thin liquid was significantly shorter than all other liquid swallow tasks, while solid had an inverse effect. Compared to 5 mL thin liquid, all other swallow tasks resulted in significantly wider UESmax. Mildly and moderately thick liquid significantly increased UESOdur when isolating viscosity. UESmax was significantly wider with mildly and moderately thick liquid and puree than thin liquid. When isolating volume, cup sip thin liquid increased both measures significantly relative to 5 mL. Age, sex, and swallow task can influence the normal timing and extent of UES movement. These collective effects contribute to normal variability in UES function and should be considered for clinical decision-making. 4 Laryngoscope, 134:2306-2315, 2024.

Patterns of Esophageal Motility and Bolus Transit in Children With Repaired Esophageal Atresia

Background: Esophageal dysmotility is common after esophageal atresia (EA) repair. Esophageal manometry (HRM) is the gold standard to investigate motility. We aim to characterize esophageal dysmotility and bolus transit for liquid and solids in children with repaired EA. Method: Retrospective analysis of HRM from children with repaired EA. Five liquid and 5 solid swallows per child were assessed for the standard manometric measurement and peristalsis pattern. Impedance tracings were used to assess bolus transit. Results: Ninety measurements were assessed from 9 patients, 44% Females. Mean age was 10.5 (±4.6) years. All children had dysphagia and anastomotic strictures were excluded. None of the children had intact peristalsis, 44.4% of the liquid swallows were failed, 33.3% fragmented and 22.2% ineffective. 44.4% of the solid swallows were failed, 44.4% fragmented and 11.1% ineffective. 33.3% had incomplete bolus transit in the whole esophagus, 44.4% in the upper and 11% in the lower esophagus. Mean peristalsis break for liquid was 7 cm (±2.1) and for solid was 5.9 cm (±3.2) P .025. Conclusion: Impaired esophageal motility is universal post EA repair. Failed and ineffective peristalsis predominate with incomplete bolus transit and large peristalsis breaks after liquid and solid swallows. HRM can provide clinical guidance, diagnostic and prognostic information post EA repair.

Pressure dynamics of the esophagogastric junction at rest and during inspiratory maneuvers after Nissen fundoplication.

Low sphincter pressure and inability of the crural diaphragm to elevate it at the esophagogastric junction are important pathophysiological mechanisms of gastroesophageal reflux disease (GERD). The object of this study was to depict how Nissen fundoplication changed the resting and inspiratory pressures of the anti-reflux barrier. We selected 14 patients (eight males; mean age 42.7years; mean body mass index 27.8) for surgery. They answered symptoms questionnaires and underwent high-resolution manometry (HRM) before and 6months after Nissen fundoplication. We used a standard manometric protocol (resting and liquid swallows) and assessment of esophagogastric junction (EGJ) pressure metrics during standardized forced inspiratory maneuvers against increasing loads (Threshold Maneuvers). We used the Wilcoxon test for comparison of pre and postoperative data. After fundoplication, heartburn and regurgitation scores diminished remarkably (from 4.5 and 2, respectively, to zero; P = 0.002 and P = 0.0005, respective medians). Also, the median expiratory EGJ pressure had a significant increase from 8.1 to 18.1mmHg (P = 0.002), while mean respiratory pressure and EGJ contractility integral (EGJ-CI) increased without statistical significance (P = 0.064 and P = 0.06, respectively). Axial EGJ displacement was lower after fundoplication. The EGJ relaxation pressure (P = 0.001), the mean distal esophageal intrabolus pressure (P = 0.01) and the distal latency (P = 0.017) increased after fundoplication. There was a reduction in the contraction front velocity (P = 0.043). During evaluation with standardized inspiratory maneuvers, the inspiratory EGJ pressures (under loads of 12, 24, 36 and 48 cmH2O) were lower after surgery for all loads (median for load 12 cmH2O: 145.6 vs. 102.7mmHg; P = 0.004). Fundoplication and hiatal closure increased the expiratory EGJ pressure and promoted a great GERD symptom relief. The surgery seemed to overcompensate a reduced EGJ mobility and inspiratory pressure.

Clinical utility of the solid meal test during high-resolution esophageal manometry. A study in a Latin American population

Introduction and aimsThe solid test meal (STM) is a challenge test that is done during esophageal manometry and appears to increase the diagnostic yield of the study. The aim of our analysis was to establish the normal values for STM and evaluate its clinical utility in a group of Latin American patients with esophageal disorders versus healthy controls. Material and methodsA cross-sectional study was conducted on a group of healthy controls and consecutive patients that underwent high-resolution esophageal manometry, in which STM was done at the final part of the study and consisted of asking the subjects to eat 200 g of precooked rice. The results were compared during the conventional protocol and the STM. ResultsTwenty-five controls and 93 patients were evaluated. The majority of the controls (92%) completed the test in under 8 min. The STM changed the manometric diagnosis in 38% of the cases. The STM diagnosed 21% more major motor disorders than the conventional protocol; it doubled the cases of esophageal spasm and quadrupled the cases of jackhammer esophagus, whereas it demonstrated normal esophageal peristalsis in 43% of the cases with a previous diagnosis of ineffective esophageal motility. ConclusionsOur study confirms the fact that complementary STM during esophageal manometry adds information and enables a more physiologic assessment of esophageal motor function to be made, compared with liquid swallows, in patients with esophageal motor disorders.

Utilidad clínica de la prueba de comida sólida durante la realización de manometría esofágica de alta resolución. Un estudio en población latinoamericana

Introduction and aimsThe solid test meal (STM) is a challenge test that is done during esophageal manometry and appears to increase the diagnostic yield of the study. The aim of our analysis was to establish the normal values for STM and evaluate its clinical utility in a group of Latin American patients with esophageal disorders versus healthy controls. Material and methodsA cross-sectional study was conducted on a group of healthy controls and consecutive patients that underwent high-resolution esophageal manometry, in which STM was done at the final part of the study and consisted of asking the subjects to eat 200g of precooked rice. The results were compared during the conventional protocol and the STM. ResultsTwenty-five controls and 93 patients were evaluated. The majority of the controls (92%) completed the test in under 8min. The STM changed the manometric diagnosis in 38% of the cases. The STM diagnosed 21% more major motor disorders than the conventional protocol; it doubled the cases of esophageal spasm and quadrupled the cases of jackhammer esophagus, whereas it demonstrated normal esophageal peristalsis in 43% of the cases with a previous diagnosis of ineffective esophageal motility. ConclusionsOur study confirms the fact that complementary STM during esophageal manometry adds information and enables a more physiologic assessment of esophageal motor function to be made, compared with liquid swallows, in patients with esophageal motor disorders.

Swallow Reaction Time in Healthy Adults

Purpose: Swallow onset is commonly characterized by bolus location. Quantifying this swallow event using swallow reaction time (SRT) may further inform swallow assessment, but few studies have established normative reference values for SRT using a large sample size and well-tested, standardized, and validated videofluoroscopic swallow study (VFSS) approach. The purpose of this study was to investigate SRT in a large cohort of healthy adults and the effects of demographic (age, sex) and bolus (viscosity, volume) characteristics on SRT using the Modified Barium Swallow Impairment Profile approach. Method: Archival VFSSs of 195 healthy adults (21–89 years) were analyzed to obtain SRT across seven standardized swallow tasks ranging from thin to extremely thick liquid and a solid. Descriptive statistics were generated for age, sex, viscosity, and volume. Generalized estimating equation models were computed to explore the effects of demographic and bolus characteristics on SRT. Results: Variability in SRT was observed among healthy adults across all swallow tasks. Only viscosity significantly influenced SRT. Specifically, thicker viscosities resulted in longer SRT. Conclusions: Wide variability in SRT was observed in this large cohort of healthy adults across various liquid swallow tasks and a solid task. Thicker viscosities, in particular, yielded longer SRT and should be considered a normal variant. This study further provides normative SRT data related to a commonly used VFSS approach, which clinicians can use as reference values for their patient data.

Defining Normal Sequential Swallowing Biomechanics.

Little is known about the physiology of a common fluid ingestion pattern-sequential swallowing. This study investigated sequential swallowing biomechanics in healthy adults. Archival normative videofluoroscopic swallow studies were analyzed for hyolaryngeal complex (HLC) patterning and biomechanical measures from the first 2 swallows of a 90-mL thin liquid sequential swallow task. The effects of age, sex, HLC type, and swallow order were explored. Eighty-eight participants were included in the primary analyses as they performed sequential swallows. HLC Type I (airway opens, epiglottis approaches baseline) and Type II (airway remains closed, epiglottis remains inverted) most commonly occurred (47% each), followed by Type III (mixed, 6%). Age was significantly associated with Type II and longer hypopharyngeal transit, total pharyngeal transit (TPT), swallow reaction time (SRT), and duration to maximum hyoid elevation. Males demonstrated significantly greater maximum hyoid displacement (Hmax) and longer duration of maximum hyoid displacement. Significantly larger maximum hyoid-to-larynx approximation was linked to the first swallow, while the subsequent swallow had significantly longer oropharyngeal transit, TPT, and SRT. Secondary analyses included an additional 91 participants who performed a series of discrete swallows for the same swallow task. Type II had significantly greater Hmax than Type I and series of discrete swallows. Sequential swallowing biomechanics differ from discrete swallows, and normal variance exists among healthy adults. In vulnerable populations, sequential swallowing may challenge swallow coordination and airway protection. Normative data allow comparison to dysphagic populations. Systematic efforts are needed to further standardize a definition for sequential swallowing.

Delayed Gastric Emptying After Sleeve Gastrectomy Is Associated with Poor Weight Loss

BackgroundIntermediate to long-term weight regain is a major challenge following sleeve gastrectomy (SG). Physiological changes that mediate the extent of weight loss remain unclear. We aimed to determine if there were specific esophago-gastric transit and emptying alterations associated with weight regain.Material and MethodsParticipants greater than 12 months post-SG were categorized into optimal (n = 29) and poor weight loss (PWL) (n = 72). All patients underwent a liquid contrast barium swallow demonstrating normal post-surgical anatomy and a protocolized nuclear scintigraphy designed specifically to characterize gastric emptying following SG.ResultsThe %total weight loss in the optimal group was 26.2 ± 10.5 vs. 14.3 ± 8.8% in the PWL group (p = 0.001). Scintigraphy showed PWL had relatively increased gastric emptying half-time (GE 1/2t) 35 (IQR 23) min vs 19 (IQR 5.5) min (p = 0.001). The multivariate regressions delineated GE 1/2t as the best diagnostic measure for PWL (OR 1.16; CI 1.04–1.29, p-value 0.021). The probability of PWL increased by 16% for every 1-min increase above 21 min of GE 1/2t. A threshold of 21 min was found to have 88% sensitivity and 69% specificity predicting poor weight loss.ConclusionGastric emptying half-times greater than 21 min appear to reliably correlate with poor weight loss following SG. Additionally, further elevations above 21 min in emptying half-time increase the risk of poor weight loss. We have shown nuclear scintigraphy represents a simple and accurate diagnostic tool in patients who experience poor weight loss after SG, provided substantially altered reporting references in interpreting nuclear scintigraphy are applied.Graphical abstract

Effects of the GABA(B) agonist baclofen on volitional swallowing in normal subjects.

The GABA(B) receptor agonist baclofen is known to suppress the rate of spontaneous swallowing but not pharyngeal muscle contraction. The extent to which baclofen may alter volitional swallowing is not currently known. We investigated the effects of baclofen in healthy subjects, hypothesizing that baclofen exposure would alter volume-regulation and/or piecemeal deglutition behaviors during volitional swallowing attempts. Pharyngeal high-resolution manometry impedance (P-HRM-I) protocol was used to assess swallowing function of 22 healthy adult volunteers (median 29 years) who were investigated on two occasions, receiving 40 mg baclofen (oral) 1 h before study, or placebo (randomized). Standard swallow function variables recommended by the pharyngeal HRM Working Group were derived for 5ml, 10ml, and 20 ml volumes of thin and extremely thick liquid challenges. Multiple swallow behaviors, comprising two swallows <5s apart, were characterized. The spontaneous swallow rate was also determined. Baclofen exposure had no overall significant effect on swallow variables. Upper esophageal sphincter pressure was weaker during exposure to baclofen, during both the pre-deglutitive and post-deglutitive phases of the swallow (p < 0.05 during thick liquid swallows). Piecemeal swallows, where the bolus is separated in two potions, were significantly more common during 20 ml boluses (p=0.002). Baclofen decreased the frequency of piecemeal deglutition overall. Baclofen has limited to no effect on volitional swallowing measures, however, does reduce the likelihood of initiation of piecemeal deglutition to large volume challenges.

S2419 A Motility Study in a Patient With Isolated Diaphragmatic Agenesis: An Interesting Study in a Very Rare Entity!

Introduction: Diaphragmatic agenesis is a very rare congenital defect. Diagnosis is typically made in infancy and it is commonly associated with other congenital malformations and high mortality. However, it has also been described in the literature as a distinct clinical entity with potentially later in life diagnosis, as in the case reported here. Case Description/Methods: Our subject is a 57-year-old male who was diagnosed to have diaphragmatic agenesis at the age of 45 during a thoracotomy for a suspected diaphragmatic hernia. He presented to the gastroenterology clinic with a chief complaint of life-long intermittent but progressive dysphagia to both solids and liquids. Chest x-ray showed bowel loops and air-fluid level in the left-side of the chest with a cardiac and a mediastinal shift to the right side. Barium swallow was done and was negative for any abnormalities. A motility study was also done and with details showing in Tables 1-4 (Figure). Findings of the motility study are summarized as the following: 1) Normal resting pressure at lower esophageal sphincter with incomplete relaxation during swallows (high IRP), 2) Normal amplitude peristaltic contractions in esophageal body (Normal DCI), 3) Complete bolus transition, 4) Esophagogastric morphology I, and 5) Normal upper esophageal sphincter resting pressure. A chest X-ray obtained and attached in figure A shows the position of the probe used in the esophageal manometry with the gastroesophageal junction in the thoracic cavity. Figure B shows our patient's manometric study evaluating pressure changes that occurred during liquid swallowing. The diagnosis of esophagogastric junction (EGJ) outflow obstruction was made based on study results. Discussion: Esophagogastric junction outflow obstruction is a major motility disorder based on the Chicago Classification of esophageal motility disorders. This entity involves a heterogenous group of underlying etiologies with diaphragmatic agenesis being one potential but rare cause evidenced by our reported case. Management of (EGJ) outflow obstruction is dependent on the underlying etiology.Figure 1.: (Top) Motility study details. A) Chest Xray showing the position of the probe used in the esophageal manometry. B) Patient's manometric study evaluating pressure changes that occurred during liquid swallowing.

Using high resolution manometry impedance to diagnose upper esophageal sphincter and pharyngeal motor disorders.

Oro-pharyngeal pathophysiology, including upper esophageal sphincter (UES) and pharyngeal disorders, can be assessed by pharyngeal high-resolution manometry impedance (P-HRM-I). We aimed to establish methodology to diagnose disorders utilizing P-HRM-I, hypothesizing that the objective measures could be used to diagnose disordered deglutition evidenced by greater aspiration scores. Patients (n=509, 18-91 years) were compared to controls (n=120, 20-94 years). Variables measuring UES relaxation, UES opening extent, intrabolus pressure, and pharyngeal contractile strength were derived for 10ml liquid swallows. Three associated pharyngeal pressurization patterns, which may be indicative of obstructed flow, were characterized: pan-pressurization (Type 1), distal compartmentalized pressurization (Type 2), and transient pressurization (Type 3). Deglutitive aspiration was determined from video fluoroscopy. UES relaxation pressure was best able to differentiate patients from controls (T 6.528, p < 0.0001). Patients with abnormal relaxation pressure (>8 mmHg) more frequently exhibited pharyngeal pressurization patterns and had adjunct evidence of reduced luminal distensibility (high intrabolus pressure and/or reduced UES opening). Utilizing this information, a diagnostic scheme was devised identifying 138 patients with UES disorder. A further 96 patients without evidence of UES disorder had abnormally weak pharyngeal pressures, confirming propulsive disorder. Amongst a sub-sample of 320 patients undergoing video fluoroscopy, those with pharyngeal pressurizations and adjunct evidence of reduced UES relaxation and/or distensibility had higher aspiration scores (Chi-square 60.169, p < 0.0001). P-HRM-I can provide evidence for UES disorder based on pharyngeal pressurization patterns and abnormal findings for UES relaxation pressure, UES opening, and intrabolus pressure. Measuring pharyngeal contractility requires further optimization.

Relationship Between Pharyngeal Residues Assessed by Bolus Residue Scale or Normalized Residue Ratio SCALE and Risk of Aspiration in Head and Neck Cancer Who Underwent Videofluoroscopy.

Dysphagia affects 60-75% of patients treated for head and neck cancer (HNC). We aimed to evaluate the association between residue severity and airway invasion severity using a videofluoroscopic swallowing study and identify risk factors for poor penetration-aspiration outcomes in patients with dysphagia treated for HNC. Penetration-Aspiration Scale (PAS) was used to assess airway invasion severity, while residue severity was assessed using both the Bolus Residue Scale (BRS) for residue location and the Normalized Residue Ratio Scale (NRRS) for residue amount. Relevant covariates were adjusted in the logistic regression models to account for potential confounding. Significantly higher abnormal PAS was reported for increased piriform sinus NRRS (NRRSp) [odds ratio (OR), 4.81; p = 0.042] with liquid swallowing and increased BRS value (OR, 1.52; p = 0.014) for semi-liquid swallowing in multivariate analysis. Tumor location, older age, and poorer Functional Oral Intake Scale (FOIS) were significant factors for abnormal PAS in both texture swallowings. After adjusting for confounding factors (sex, age, and FOIS score), NRRS model in liquid swallowing (area under the curve [AUC], 0.83; standard error = 0.04, 95% confidence interval [CI]: 0.75, 0.91) and BRS in semi-liquid swallowing (AUC, 0.83; SE = 0.04; 95% CI: 0.76, 0.91) predicted abnormal PAS. The results indicate that while assessing residue and swallowing aspiration in patients with HNC, it is important to consider age, tumor location, and functional swallowing status. The good predictability of abnormal PAS with BRS and NRRS indicated that residue location and amount were both related to the aspiration event in patients with HNC.