UES Opening and Cricopharyngeal Bar in Nondysphagic Elderly and Nonelderly Adults

The intent of the study was to investigate upper esophageal sphincter (UES) opening and cricopharyngeal bar, and their relationship to other swallowing variables, in elderly, nondysphagic subjects. Extent and duration of UES opening, hypopharyngeal transit time, hyoid displacement, hyoid-to-larynx approximation, and incomplete pharyngeal clearing were determined from fluoroscopic swallow studies in 84 nonelderly control subjects and 88 elderly subjects. No differences in these measures were found between elderly subjects with and without medical conditions, and data were subsequently pooled. Mild, moderate, or marked cricopharyngeal bars were identified in more than 30% of elderly subjects, and subsequent analyses were performed on the control group, the elderly group without bars, and the elderly group with bars. Maximum opening of the UES in the elderly bar group was significantly reduced compared with that of the elderly group without bars and the nonelderly control group. However, timing measures did not differentiate elderly subjects with bars from other elderly subjects and they suggest that prolonged transit times in the elderly cannot be explained by the presence of a cricopharyngeal bar. With the exception of hyoid displacement, all variables investigated differed significantly between the nonelderly and one or both of the elderly groups. With the exception of UES opening, variables examined generally did not differentiate the two elderly groups.     

Pharyngeal Constriction in Elderly Dysphagic Patients Compared with Young and Elderly Nondysphagic Controls

This article reports the results of our study to determine the incidence of abnormalities in timing and extent of pharyngeal constriction in an elderly population with complaints of dysphagia. We performed a retrospective analysis of videofluoroscopic studies, i.e., dynamic swallow studies, that were performed between 1996 and 1999. Included in the study were patients over 65 years old without an obvious medical or surgical cause for their dysphagia complaints. The timing of maximum pharyngeal constriction was measured relative to the onset of bolus pharyngeal transit, relative to the arrival of the bolus at the upper esophageal sphincter, and relative to the exit of the tail of the bolus from the upper esophageal sphincter. The extent of maximum pharyngeal constriction was measured from a lateral view. Patient data were compared with data gathered from young (18-62 years old) nondysphagic controls and with data gathered from elderly (67-83 years old) nondysphagic controls. We found that 73% of the patient population demonstrated incomplete pharyngeal constriction relative to controls, although the timing of pharyngeal constriction remained coordinated relative to the position of the bolus in the pharynx. Poor pharyngeal constriction, suggestive of pharyngeal weakness, contributed to 75% of the cases of aspiration.     

Structural Displacements in Normal Swallowing: A Videofluoroscopic Study

Dynamic videofluoroscopic swallow studies were performed on 60 normal adult volunteers to establish normative data for displacement of upper aerodigestive tract structures during deglutition. Variables evaluated included hyoid bone displacement, larynx-to-hyoid bone approximation, pharyngeal constriction, and the extent of pharyngoesophageal sphincter (PES) opening during liquid swallows of 1, 3, and 20 cc. Results showed direct relationships between bolus size and hyoid displacement, between bolus size and PES opening, and between bolus size and pharyngeal constriction. Only hyoid-to-larynx approximation remained unchanged across bolus sizes. Sex differences were noted for all variables except PES opening. Reliability for most measurement variables was excellent. To our knowledge, normative data for pharyngeal constriction and larynx-to-hyoid approximation have not previously been described.     

Hyoid-Bolus Transit Latencies in Normal Swallow

Pharyngeal swallow delay is frequently found in dysphagic patients and is thought to be a factor in a range of swallowing problems, including aspiration. Implicit in notions of swallow “delay” is a temporal interval between two events that is longer than normal. However, there appears to be little agreement about which referent events should be considered in determining delay. A number of pharyngeal bolus transit points and various pharyngeal gestures have been used in delays determined from fluoroscopic evidence, and other referents have been used in electromyographic and manometric studies of swallow. In this study latencies between the first movement of the hyoid and several pharyngeal bolus transit points were calculated from fluoroscopic swallow studies in normal nondysphagic adults. Means and standard deviations of these latencies are provided for a 3-cc and a 20-cc bolus and for both nonelderly and elderly adults. The data may be a useful resource for relating the specific latencies investigated to concepts of pharyngeal swallow delay, in particular, when assessing videofluoroscopic studies using a similar protocol.     

Maximum Hyoid Displacement in Normal Swallowing

Vertical and anterior displacement of the hyoid bone is a critical biomechanical component of normal swallowing function. The purpose of this study was to evaluate the maximal vertical and anterior displacement of the hyoid bone during oropharyngeal swallowing. A retrospective review of video-fluoroscopic swallowing exams in 40 normal subjects varying by age and gender was performed. Means and standard deviations for both vertical and anterior displacement were analyzed on both 5-ml and 10-ml thin liquids using an ImageJ program. Age and gender differences were submitted to a repeated-measures one-way analysis of variance. There was a significant difference between younger and older subjects for anterior displacement of the hyoid bone during the swallow but not for vertical displacement. No significant differences between male and female subjects were observed. Anterior displacement of the hyoid bone decreased with increasing age. This reduction may be related to muscle weakness. However, older people may adapt to preserve airway protection.     

Hyoid Bone and Laryngeal Movement Dependent Upon Presence of a Tracheotomy Tube

The aim of this prospective, consecutive study was to investigate the biomechanical effects, if any, of the presence of a tracheotomy tube and tube cuff status, tube capping status, and aspiration status on movement of the hyoid bone and larynx during normal swallowing. Seven adult patients (5 male, 2 female) with an age range of 46–82 years (mean = 63 years) participated. Criteria for inclusion were no history of cancer of or surgery to the head and neck (except tracheotomy), normal cognition, normal swallowing, and ability to tolerate decannulation. Digital videofluoroscopic swallowing studies were performed at 30 frames/s and with each patient seated upright in the lateral plane. Variables evaluated included maximum hyoid bone displacement and larynx-to-hyoid bone approximation under three randomized conditions: tracheotomy tube in and open with a 5-cc air-inflated cuff; tracheotomy tube in and capped with deflated cuff; and tracheotomy tube out (decannulated). Differences between maximum hyoid bone displacement and larynx-to-hyoid approximation (cm) based on presence/absence of a tracheotomy tube, tube cuff status, and tube capping status were analyzed with the Student’s t test. Reliability testing with a Pearson product moment correlation was performed on 21% of the data. No significant differences (p > 0.05) were found for both maximum hyoid bone displacement and larynx-to-hyoid bone approximation during normal swallowing based on tracheotomy tube presence, tube cuff status, or tube capping status. Intraobserver reliability for combined measurements of maximum hyoid displacement and larynx-to-hyoid approximation was r = 0.97 and interobserver reliability for the absence of aspiration was 100%. For the first time with objective data it was shown that the presence of a tracheotomy tube did not significantly alter two important components of normal pharyngeal swallow biomechanics, i.e., hyoid bone movement and laryngeal excursion. The hypothesis that a tracheotomy tube tethers the larynx thereby preventing hyoid bone and laryngeal movement during normal swallowing is not supported.     

Common Medical Conditions in the Elderly:Impact on Pharyngeal Bolus Transit

Deglutition in the elderly may be impacted by the sequelae of medical diseases. It is unknown if the long-term presence of common medical diseases, such as arthritis and hypertension, leads to changes in neurologic and muscular function and thus swallowing ability. The aim of this project was to determine if the duration of bolus pharyngeal transit in nondysphagic elderly individuals with chronic medical problems is longer than that measured in nondysphagic elderly individuals without medical problems. Videofluoroscopic swallowing studies were performed on 63 elderly subjects with a variety of well-controlled medical problems and on 23 elderly subjects with no medical problems. The mean timing of pharyngeal bolus transit was compared between the two groups. The relationship between the presence of medical problems and the likelihood of transit times prolonged beyond two standard deviations of the mean transit time found in 60 younger normal controls was also analyzed. Findings included significantly prolonged pharyngeal transit time in the group of subjects with medical problems compared with those subjects without medical problems for a small bolus size. Those individuals with hypertension demonstrated the most significant delays in bolus transit. The presence of medical problems did correlate with an increased likelihood of prolonged transit times. This preliminary study indicates that medical problems common in elderly populations are associated with a deterioration of swallowing function and that changes identified in elderly individuals may not be due to aging alone.     

Relation of bolus size and pharyngeal swallow

To study the influence of bolus size on pharyngeal swallow, 20 dysphagic patients and 10 nondysphagic volunteers were examined cineradiographically while swallowing a bolus of 2.5, 5, 10, and 20 ml. Ten patients and 10 volunteers swallowed boluses in increasing volume while 10 patients swallowed boluses of decreasing volume. The movement of the hyoid bone occurred in a two-step fashion irrespective of the bolus size, and in all individuals. The speed of the apex of the bolus through the pharynx, measured by frame counting, increased with increasing size of the bolus. The speed of the peristaltic wave, as measured between vallecula and the PE segment, did not change with bolus size. Boluses of 10 or 20 ml caused penetration of barium into the larynx in 7 of the patients but in none of the volunteers. Our results suggest that pharyngeal constrictor activity, in terms of speed of peristalsis, is constant and not influenced by bolus volume.     

Quantitative aspects of swallowing in an elderly nondysphagic population

The prevalence of swallowing impairment increases with age and is a major health care problem in the elderly. It has been assumed that age-related changes in nerves and muscles hamper muscle strength and coordination of swallowing. However, it is unclear what impairment is related to primary aging and what is the consequence of diseases prevalent in the elderly (secondary aging). In order to quantify swallowing in nondysphagic elderly we used the noninvasive ROSS (Repetitive Oral Suction Swallow) test. A total of 53 individuals aged 76±5 years (mean±SD) were examined. We found that the nondysphagic elderly demonstrated significant differences compared with young individuals in 10 of 17 measured variables, i.e., decreased peak suction pressure, increased frequency of multiple swallows after one ingestion, increased frequency of polyphasic laryngeal movements, increased frequency of inspiration after swallowing, and increased frequency of coughing during or after swallowing. Therefore, primary aging mainly seems to influence coordination of swallowing, but oral and pharyngeal swallow per se seem to be unaffected.     

Maximal Hyoid Excursion in Poststroke Patients

Reduced maximal hyoid excursion has been suspected as one of the primary physiologic causes of aspiration after a stroke. Vertical and anterior displacement of hyoid excursion is critical to epiglottic closure for airway protection and the opening of the upper esophageal sphincter (UES). Without these carefully timed and well-executed components, the bolus cannot pass safely through the pharynx. The purpose of this study was to evaluate vertical and anterior displacement of the hyoid bone during oropharyngeal swallowing in two groups of subjects: (1) 16 stroke patients who aspirate before or during the swallow (aspirators), and (2) 33 stroke patients who do not aspirate (nonaspirators). Means and standard deviations for anterior and vertical displacement were analyzed for 5- and 10-ml thin-liquid boluses using the ImageJ program (136 swallows). A two-way analysis of variance (ANOVA) was run with group and volume as independent variables. There was no significant difference between the two groups for vertical or anterior displacement. Maximal anterior displacement of the hyoid bone was slightly longer in nonaspirators than in aspirators. Aspiration before and during the swallow may be related more to the triggering of pharyngeal swallow than to the maximal extent of hyoid excursion.     

Normal adult swallowing of liquid and viscous material: Scintigraphic data on bolus transit and oropharyngeal residues

Scintigraphic data are provided for 20 normal control subjects, 39–65 years of age. Each subject swallowed 10 cc of water and 10 cc of a more viscous material (1,100 centipoise) consisting of apple juice thickened with Thick-It, a commercial food thickener. The test substances were combined with 2.5 mCi Tc-99m sulfur colloid. Scintigraphic data were acquired in dynamic mode for 10 sec at 25 frames/sec as the subjects swallowed. Time-activity (TA) data were used to compute transit times, percentage residues in the mouth and pharynx, percent ingested, and a derived swallow efficiency score. The liquid was ingested in a single swallow by all subjects, and 9 cc was actually tranferred to the esophagus. In contrast, for the viscous material, 11/20 subjects performed a second clearing swallow within the 10-sec interval. On the first swallow with the viscous substance, an average of 7 cc was transferred to the esophagus. Scintigraphy offers an excellent technique for determining natural and preferred volumes for swallowing a variety of bolus consistencies, since it can quantify the volume of each swallow or partial swallow. In this group of subjects the oral discharge time was shorter with the viscous material than with the water, but the pharyngeal transit times were not significantly different for the two bolus consistencies. Numerical efficiency scores were lower for the viscous material, indicating that such a measure is bolus dependent.     

Bolus Location at the Initiation of the Pharyngeal Stage of Swallowing in Healthy Older Adults

This study characterized the vertical position of the bolus head at the onset of the pharyngeal swallow in healthy older adults. Lateral-view videofluoroscopic (VF) images were obtained from ten healthy volunteers (age-71.6 ± 7.5 years, mean± SD) as they swallowed 5-cc thin liquid barium aliquots. For each swallow, the bolus head and several anatomic landmarks were digitally recorded from the image in which pharyngeal swallow-related hyoid bone elevation began. Vertical distance between the bolus head and the intersection of the tongue base and mandibular ramus (TMI) was computed. Bolus head position at swallow onset ranged from 47.4-mm above to 34.9-mm below the TMI (2.2 ± 14.4-mm, mean ± SD). Although the bolus head was below the level of the TMI for the majority of swallows, neither penetration nor aspiration occurred. For individual subjects, mean bolus head position ranged from 25.8 ± 5.0-mm above to 15.5 ± 6.5-mm below the TMI. Whereas five of ten subjects initiated the pharyngeal swallow with the bolus head consistently above or consistently below the TMI, five subjects initiated swallowing with the bolus head either above or below the TMI across trials. Older adults commonly initiate thin-liquid swallows with the bolus head well below the TMI without associated penetration or aspiration. Thus, bolus position alone does not differentiate between normal and pathologic swallowing within the healthy elderly. Bolus position at pharyngeal swallow onset can vary substantially from trial to trial within an individual, suggesting that the triggering of swallowing depends on multiple influences. This research was supported by NSERC grant No. 0GPO171208 and an Ontario Ministry of Health Career Scientist Award to REM.     

Effect of Posture on Deglutitive Biomechanics in Healthy Individuals

The purpose of this study was to assess displacement of oropharyngeal structures, particularly the hyoid bone and velum, and variations in timing of the pharyngeal stage of swallowing in the upright versus the supine position. Twelve Caucasian adult subjects between 19 and 27 years of age participated. Subjects were recorded swallowing 7 cc of liquid barium in the upright and supine positions. The hyoid bone had a significantly greater amount of anterior displacement while in the supine position compared to that of the upright position (p < 0.01). While in the upright position, the velum comes to a fully elevated position at nearly the same time as the initiation of the pharyngeal swallow (within an average of 27 ms of each other), whereas in the supine position the velum continues to elevate on average 115 ms after the initiation of the pharyngeal swallow. Results indicated a significant difference (p < 0.05) in the amount of velar movement from rest to the fully elevated position between the upright and supine positions for female subjects. The results from the study demonstrate variations in hyoid displacement, velar movement, and bolus movement through the pharynx with respect to the two body positions and the subjects’ gender.     

Ligaments of the larynx and the adjacent pharynx and esophagus

Two ligament systems of the larynx are demonstrated by dissection. The suspensory ligament of the esophagus is attached to the posterior aspect of the cricoid cartilage and is also a part of the fascial sheath which is common to the hyoid, thyroid, and cricoid. The ligaments at the inner margins of the vocal, ventricular, and aryepiglottic folds are distinctive in site and, inferentially, in function. The aryepiglottic ligaments join at the incisura between the arytenoid cartilages and are continued as the corniculopharyngeal ligament which splays into the flexible tissues in the anterior wall of the hypopharynx, posterior to the suspensory ligament of the esophagus. These ligament systems are involved in two different actions in swallow. The gross superior and anterior motions of the larynx are transmitted to the esophagus by the suspensory ligament, so that the esophagus is elevated in relation to the bolus and is also opened. These esophageal displacements resemble, in effect, the swallow displacements of the pharyngoesophageal segment and of the constrictor wall of the hypopharynx. The marginal ligaments of the laryngeal folds help to implement the constriction and closure of the larynx during swallow. By anatomical inference, the corniculopharyngeal ligament effects vertical traction within the flexible tissues of the anterior wall of the hypopharynx.     

Influence of cold stimulation on the normal pharyngeal swallow response

We examined the potential influence of cold stimulation of the anterior tonsillar pillars, before and after topical anesthesia, on the temporal linkage between the oral and pharyngeal components of the swallow. We hypothesized that if elicitation of the pharyngeal swallow were dependent upon stimulation of faucial mucosal receptors this response would be facilitated by cold tactile stimulation and inhibited by topical anesthesia. In 14 healthy volunteers undergoing simultaneous videoradiography and manometry we measured and compared regional transit and clearance times, and the timing of hyoid motion, upper esophageal sphincter relaxation, and opening within the swallow sequence. There was a significant, volume-dependent forward shift in timings of hyoid motion, upper esophageal sphincter (UES) relaxation profile, and opening which were influenced neither by cold stimulation nor topical anesthesia. Regional transit and clearance times and UES coordination were not influenced by cold stimulation. Pharyngeal clearance time was prolonged by tonsillar pillar anesthesia due to earlier arrival of the bolus head at this region (p=0.002). We conclude that the normal pharyngeal swallow response is neither facilitated nor inhibited by prior cold tactile stimulation or topical anesthesia to the tonsillar pillars, respectively. These observations do not support the hypothesis that elicitation of the pharyngeal swallow response is dependent upon stimulation of mucosal receptors in the tonsillar arches.     

Timing of Events in Normal Swallowing: A Videofluoroscopic Study

Dynamic videofluoroscopic swallow studies were performed on 60 normal adult volunteers to establish normative data for clinically useful timing measures. The relation of swallowing gesture timing to the timing of actual bolus transit was of particular interest because it provides insight into the physiology of larger bolus volume accommodation. Parameters evaluated include the timing of bolus pharyngeal transit, soft palate elevation, aryepiglottic fold elevation and supraglottic closure, arrival of the bolus in the vallecula, hyoid bone displacement onset and duration, arrival of the bolus at the pharyngoesophageal sphincter, maximum pharyngeal constriction, and pharyngoesophageal sphincter opening. These parameters represent events required for normal deglutition, can be used to identify abnormalities in dysphagic patients, and provide a basis for comparison of swallowing performance both within and between patients. In addition, our experience has shown them to be reliably obtained. Other investigators have reported some of the measurements. However, to our knowledge, normative data for timing of aryepiglottic fold elevation, soft palate elevation and closure, and maximum pharyngeal constriction have not been described. Other measures included in the present study may provide alternatives when conventional measures cannot be obtained in selected patients. The relevance and clinical utility of new and alternative measures, in particular, are discussed.     

The Effects of Cervical Bracing Upon Swallowing in Young,Normal, Healthy Volunteers

Abstract The purpose of this study was to evaluate radiographically the effects of cervical bracing upon swallowing thin liquids and solid food in normal adults under three cervical bracing conditions. This was a prospective, repeated measures design study. Seventeen healthy adult volunteers between the ages of 30 and 50 were recruited from hospital staff. All subjects reported no previous history of swallowing difficulty or diseases that might affect swallowing. Subjects were radiographically observed swallowing thin liquids and solid food without cervical bracing and with three common cervical orthoses (Philadelphia collar, SOMI, and halo-vest brace). Order of bracing and type of bolus were randomized. Changes in swallowing function (point of initiation of swallow response, presence of pharyngeal residue, airway penetration, hyoid bone movement, diameter of oropharyngeal airway, and durational measurements) were analyzed by two independent raters. Eighty-two percent (14/17) of the subjects demonstrated radiographic changes under one or more of the bracing conditions. Forty-seven percent (8/17) of subjects demonstrated changes with point of initiation of the swallow response, 59% (10/17) demonstrated increased pharyngeal residue, and 23.5% (4/17) demonstrated changes with bolus flow with laryngeal penetration present. Aspiration did not occur under any of the bracing conditions. Changes noted in durational measurements for oral containment and total pharyngeal transit under the bracing conditions were not considered statistically significant. This study shows that cervical bracing does change swallowing physiology in normal healthy adults.     

Timing of Pharyngeal and Upper Esophageal Sphincter Pressures as a Function of Normal and Effortful Swallowing in Young Healthy Adults

The effect of effortful swallow on pharyngeal pressure and UES relaxation onsets and durations was examined. Eighteen adults, nine males and nine females (mean age = 27.9 yr), participated. Timing of pharyngeal pressure and onset and duration of UES relaxation were measured across ten trials of normal and ten trials of effortful swallows. Results revealed that manometric timing measurements are consistent across trials. The first and second statistical analyses investigated the pharyngeal pressure and UES relaxation onsets and durations, respectively. Both analyses identified a significant interaction of swallow type (i.e., effortful vs. normal) by manometric sensor location (p < 0.05). Across normal and effortful swallows, UES relaxation preceded pharyngeal pressure onsets, yet the rate of change (or degree of delay) varied across the sensors. Furthermore, the effortful swallow elicited longer pharyngeal pressure and UES relaxation durations, yet the pressure duration measured in the upper pharynx was significantly longer than that measured lower in the pharynx. These findings offer insight as to the potential positive and negative influence of the effortful swallow on pharyngeal timing.     

Quantitative assessment of swallowing in healthy adults

Swallowing has hitherto been evaluated during physical examination, radiologic barium studies, manometry, and cervical auscultation. Radiography principally demonstrates qualitative aspects of oral and pharyngeal function, whereas quantitative aspects have primarily been documented by manometry. To evaluate swallowing quantitatively, without using invasive methods or radiation, we have applied a combined test of water drinking, i.e., the Repetitive Oral Suction Swallow test (ROSS). The test provides reliable measurements of suction pressure, bolus volume, timing of important events in oral and pharyngeal swallow, and respiration. The test is described and results from 292 healthy, nondysphagic subjects are presented. We found a mean bolus volume of 25.6±8.5 ml during single swallow and 21.1±8.2 ml during stress (forced, repetitive swallow). During forced, repetitive swallow, the bolus volume was more strongly associated with suction time (r²=0.55) than with peak suction pressure (r²=0.04), indicating that suction time is more important than suction pressure in determining the bolus volume. The oral-pharyngeal transit time decreased: single swallow 0.56±0.36 sec, forced repetitive swallow 0.23±0.11 sec, as did the coefficient of variation (48% and 64%, respectively) indicating a more automatic neural process for pharyngeal function in forced, repetitive swallow. The postswallow respiration started with inspiration in 10% of studied individuals, but did not correlate with deviations in other variables in the test. Thus, postswallow inspiration must be considered as normal. The ROSS test offers a rapid and easy quantitative assessment of swallowing.     

Videomanometric Analysis of Supraglottic Swallow, Effortful Swallow, and Chin Tuck in Healthy Volunteers

Simultaneous videoradiography and solid-state manometry (videomanometry) was applied in eight healthy volunteers (four women, four men; age range 25–64 years, mean age 41 years) without swallowing problems. Three different swallowing techniques were tested; supraglottic swallow, effortful swallow, and chin tuck. Seven videoradiographic variables and six manometric variables were analyzed. The supraglottic swallowing technique did not differ significantly from that of the control swallows. The effortful swallow had a significantly (p= 0.0001) reduced hyoid–mandibular distance preswallow due to an elevation of the hyoid and the larynx, which caused a significantly (p= 0.007) reduced maximal hyoid movement and a significantly (p= 0.009) reduced laryngeal elevation during swallow. The chin tuck swallow had a significantly (p= 0.001) reduced laryngohyoid distance and also a significantly (p= 0.004) reduced hyoid–mandibular distance. The chin tuck swallow also displayed significantly (p= 0.003) weaker pharyngeal contractions. Videomanometry allows for analysis of bolus transport, movement of anatomical structures, and measurement of intraluminal pressures. These variables are important when evaluating swallowing techniques. In the present study, we made a few observations that never have been reported before. When healthy volunteers performed supraglottic swallow, they performed the technique somewhat differently. Therefore, we assume dysphagic patients would need a substantial period of training to perform a technique efficiently. Chin tuck could impair protection of the airways in dysphagic patients with weak pharyngeal constrictor muscles.