Effects of body position and bolus consistency on the manometric parameters and coordination of the upper esophageal sphincter and pharynx

The development of a solid-state intraluminal sphincter transducer has alleviated many of the problems associated with manometric studies of the upper esophageal sphincter (UES) and pharynx (P). We used this technology to study the effect of position (upright vs. supine) on resting UES pressures and the pressure dynamics of the UES/P complex during both wet and dry swallows in 11 normal volunteers and the effects of foods of different consistencies on the UES/P swallow dynamics in 10 normal volunteers. The UES/P coordination parameters were defined as the 15 time intervals that can be measured between any 2 of 6 pertinent points: the beginning, peak, and end of the pharyngeal contraction and the beginning, nadir, and end of the UES relaxation. Data from both the circumferential transducer used to measure sphincter pressures and a standard microtransducer used to measure pharyngeal pressures were collected on-line by an Apple IIe microcomputer and analyzed by programs written in our laboratory. Significant changes in swallow coordination were measured between upright and supine swallows of the same bolus size, between wet and dry swallows in the same position, and among foods of varying consistencies. Resting UES pressure was unchanged by position and pharyngeal contraction pressure was unchanged by bolus size or consistency.     

Acute thermal injury of the esophagus

Acute thermal injury to the esophagus has not been reported previously in the radiographic literature. We present a case of a young adult who developed an intramura blister that ultimately communicated with the esophageal lumen. A double-contrast esophagogram outlined the resulting mucosal flap. A brief review of other injuries to the esophagus is included.     

Aging and the esophagus: Common pathologic conditions and their effect upon swallowing in the geriatric population

Dysphagia in the elderly is most often oropharyngeal or hypopharyngeal in location and neuropathologic in etiology. Aging itself, although causing demonstrable structural and functional changes in the esophagus, does not cause any clinically relevant esophageal dysphagia. A variety of pathologic conditions seen in the geriatric population affect the esophagus and can alter esophageal function, resulting in symptomatic dysphagia. Accurate diagnosis requires a thorough evaluation performed in an unhurried fashion, often with the assistance of ancillary personnel. Treatment of these esophageal disorders is multidisciplinary and may involve dietary manipulations, the administration of medications, therapeutic endoscopic procedures, and occasionally surgery.     

Effect of head position on the dynamics of the upper esophageal sphincter and pharynx

Due to limitations in available technology it has been difficult to obtain data on upper esophageal sphincter (UES) and pharyngeal (P) function under varying physiologic conditions. We used a manometry system with solid-state intraluminal transducers, including a circumferential sphincter transducer, and computer analysis to measure pressure changes in UES and P during wet (5 ml H₂O) swallows as the head was moved through a 75 degree arc in nine normal volunteers. UES residual pressure increased markedly and duration of UES relaxation decreased with increasing head extension. Similar decreases were also seen with time between P peak and both UES nadir and UES end. There were no changes in either pharyngeal peak pressures or the duration of the pharyngeal contraction. Head extension produces major changes in UES relaxation and UES/P coordination. These effects may be clinically important when feeding neurologically impaired patients.     

Squamous cell carcinoma of the esophagus after partial gastrectomy

Twelve patients (10.4%) had a history of partial gastrectomy among the 115 patients with squamous cell carcinoma of the esophagus. The clinical characteristics, nutritional parameters, and incidences of esophagitis of the resected specimens were investigated between 11 patients with esophageal carcinoma who had partial gastrectomy for peptic ulcer diseases (Group A) and 103 patients with esophageal carcinoma without any previous history of gastrectomy (Group B). Age, sex, tumor location, clinical stages, and cigarette and alcohol consumption were not different between the two groups. Hemoglobin, mean corpuscular volume, and mean corpuscular hemoglobin level in Group A were lower than those in Group B (p<0.05). Serum zinc level in Group A was lower than that in Group B, but this difference was not significant. There was no difference in the incidences of esophagitis between the two groups. In conclusion, there is an association between partial gastrectomy and later development of squamous esophageal carcinoma. The role of malnutritional factors and gastroesophageal reflux, however, remain unclear. The long-term follow-up of patients after partial gastrectomy is warranted.     

The radiological features of primary small-cell carcinoma of the esophagus

Primary small cell carcinoma of the esophagus is a rare neoplasm. The incidence was 2% in our series. A primary lung tumor must be excluded before the diagnosis can be made. Two cases of primary small-cell carcinoma of the esophagus are presented. The radiological features of this tumor are nonspecific. Its unusual histological appearance is described. One patient had received radiotherapy for breast carcinoma 21 years earlier and the possible relationship of this type of cancer to radiotherapy has not been previously described in the literature. Each patient had a short-term response to therapy.     

Coordination of peristalsis in pharynx and esophagus

When a swallowed liquid bolus is followed from mouth to stomach in man by contrast studies or manometry, it traverses its course without hesitation even though the bolus is propelled by striated muscle contraction in the first part of its journey and smooth muscle in the latter part. The striated muscle is innervated by excitatory cholinergic nicotinic cranial nerves whereas the smooth muscle of the esophagus is innervated by the enteric nervous system (ENS) through excitatory and inhibitory nerves. These differences can be demonstrated by observing the inhibitory effects of curare and atropine, the first blocking nicotinic receptors and the second muscarinic receptors. Early students of esophageal motility recognized that peristalsis could be initiated in two ways. The first is initiated by a swallow and is called primary peristalsis and the second called secondary peristalsis is initiated by distension of the esophagus. It was proposed that primary peristalsis was initiated by a single sensory input activated by the bolus entering the pharynx which in turn activated a motor program in the brain stem. Secondary peristalsis was believed to be stimulated by multiple afferent impulses arriving from the esophagus as the bolus passed down the esophagus. More recent studies using manometric techniques have suggested that the only difference between primary and secondary peristalsis is the afferent stimuli and the effector mechanism is the same. Subsequent studies of carefully timed, paired swallows, transection of vagus nerves and esophagus, and single nerve recordings suggest that the answer lies between the two extremes noted above. Primary peristalsis is initiated by afferent stimuli from the oropharyngeal junction that triggers a stereotyped motor output from swallowing center in the brain stem to both striated and smooth muscle segments of the esophagus. If motor nerves to the striated muscle segment are interrupted no peristalsis can be generated. Severing the central nervous system (CNS) input to the smooth muscle segment does not abolish the ability of local distension to elicit a peristaltic response. Thus the CNS provides direct stimulation to the striated muscles involved in swallowing and command signals to the ENS innervating the smooth muscle. The ENS generates the final peristaltic program for the smooth muscle segment. This program may be initiated by commands from the CNS and afferent stimuli from stretch receptors in the smooth muscle segment of the esophagus.     

Distribution and origin of the peripheral innervation of rat cervical esophagus

Several neurotransmitters, neuropeptide Y (NPY), vasoactive intestinal peptide (VIP), galanin, enkephalin, calcitonin-gene related peptide (GGRP), substance P, as well as nitric oxide synthase (NOS), and the noradrenergic marker tyrosine-hydroxylase (TH) were localized by immunocytochemistry in the cervical esophagus of rat. Nerve fibers containing the neuropeptides, NOS, and TH were distributed in the myenteric plexus, around muscle bundles and small blood vessels. Injection of the retrograde tracer True Blue (TB) into the cervical esophagus resulted in the appearance of labeled nerve cell bodies in the superior cervical, the stellate, the nodose, the sphenopalatine, the dorsal root ganglia at levels C₂–C₇, and in local ganglia close to the thyroid. Most of the TB-labeled nerve cell bodies in the superior cervical ganglia contained NPY. In the stellate ganglion, a few labeled nerve cell bodies contained VIP whereas an additional few cell bodies stored NPY. In local ganglia, the majority of labeled cell bodies contained VIP. In the nodose ganglion and cervical dorsal root ganglia, the majority of the labeled nerve cell bodies stored CGRP. The results indicate that the cervical esophagus has a dense innervation with multiple neurotransmitters emanating from several ganglia. As judged by the pattern of nerve fiber distribution, they may regulate esophageal peristalsis and blood flow, some of them possibly in a cooperative manner.     

Manometric evaluation of the pharynx

Summary Over the past few years, studies of manometric techniques have improved our ability to accurately assess pharyngeal pressure events during swallowing. Solid-state transducers, circumferentially recording transducers, and on-line computer interpretation allow quantitative measurements. Studies in normal subjects will permit better recognition of pathologic states.     

The innervation of the human upper esophageal sphincter

The neuroanatomy and physiology of the human upper esophageal sphincter (UES) has long been controversial. As a result, there has been little progress in diagnosing and treating dysphagias involving this area. In this study, three specimens of the UES obtained from human autopsies were examined by Sihler's stain. This stain clears soft tissue while counterstaining the nerves, thereby allowing nerve supply to each muscle of the UES to be demonstrated. It was found that the nerve supply to each component of the UES is substantially different. The inferior pharyngeal constrictor (IPC) is supplied by a dense linear plexus which is about 1.0–1.5 cm wide and 10 cm long and located about 1.5 cm lateral to the attachment of the IPC on the thyroid lamina. The cricopharyngeal (CP) muscle receives its innervation from below via the recurrent laryngeal nerve (RLN) and from above via the pharyngeal plexus. Neural connections between the RLN and the pharyngeal plexus were observed. Finally, the upper esophagus (UE) is innervated by the RLN. The innervation pattern of each component of the UES suggests functional differences between these muscles. These observations help clarify the innervation of the UES. Accurate knowledge of the neuroanatomy of the UES is necessary for advances in diagnosis and treatment of pharyngeal dysphagia.     

Inflammatory fibroid polyp of the esophagus in an HIV-infected individual: Case study

We report an unusual case of a large esophegeal inflammatory fibroid polyp in a man infected with the human immunodeficiency virus complaining of dysphagia. Barium studies and computed tomography demonstrated a long, submucosal-appearing, distal esophageal mass which extended into a hiatal hernia. Inflammatory fibroid polyps should be considered in the differential diagnosis of submucosal and polypoid esophageal masses, although distinctive radiographic features are not found.     

Limb girdle muscular dystrophy: A radiologic and manometric study of the pharynx and esophagus

Limb girdle muscular dystrophy (LGMD) is not a recognized cause of dysphagia. However, a systematic study of pharyngoesophageal function in LGMD has not been performed or reported. We determined whether the dystrophic process involves the pharyngoesophageal musculature in 20 LGMD patients with and without complaints of deglutition. Pharyngeal and esophageal function was evaluated by conventional cineradiography and manometry. Abnormalities were demonstrated in 30% (6/20) of patients: dysphagia in 10% (2/20), an abnormal radiologic study in 30% (6/20), and an abnormal manometric study in 20% (4/20). Mean manometric pressures were not significantly different when patients were compared with a healthy, age-and sex-matched volunteer group. In 2 patients, dysfunction of the pharyngeal striated muscle was likely, or possibly, due to dystrophic affection of the upper alimentary tract. Significant upper alimentary tract dysfunction in LGMD is not common. The cause-effect relationship between the dystrophic process and the nonspecific pharyngoesophageal motility disorders is unclear and requires pathologic study.     

Prevalence of Perceived Dysphagia and Quality-of-Life Impairment in a Geriatric Population

Dysphagia is an important problem for the elderly. While well characterized in acutely ill populations, the prevalence and quality-of-life changes associated with dysphagia remain poorly defined in the community geriatric population. This study recruited individuals 65 years and older from an independent-living facility. Two validated questionnaires were used: the M.D. Anderson Dysphagia Inventory (MDADI) and the general health Short Form-12 survey (SF-12v2^TM). Each participant also answered two questions: “Do you have difficulties with swallowing?” and “Do you think that swallowing difficulties are a natural part of aging?” Fifteen percent of subjects reported difficulties with swallowing. Of these, over half suffered substantial quality-of-life impairment in one or more domains of the MDADI. With respect to the second question, 23.4% of subjects believed dysphagia to be a normal part of aging, 37.4% did not. The SF-12v2 only weakly correlated with the MDADI in this population. In conclusion, there is a relatively high prevalence of dysphagia in the community-based geriatric population; significant quality-of-life impairment is a frequent finding. General health measures do not appear to be sensitive to swallowing-related quality of life. Finally, individuals may inaccurately ascribe swallowing problems to normal aging, supporting the role of community education about dysphagia in the elderly.     

Foreign body entrapment in the esophagus of healthy subjects—A manometric and scintigraphic study

Foreign body entrapment and mucosal injury caused by oral medications are increasingly reported to occur in the upper esophagus in apparently normal subjects. We performed esophageal manometry in 40 normal volunteers to determine whether a unique motility pattern in the upper third of the esophagus predisposes to entrapment of foreign bodies at this site; 18 normal volunteers also had transit scintigraphy of a gelatine capsule filled with a radionuclide. The esophageal body was divided into five consecutive segments starting proximally, with each segment corresponding to 20% of the total length. Amplitude, slope, and velocity of the esophageal contraction were markedly decreased in the second segment compared with the other segments. Entrapment and dissolution of a gelatine capsule occurred in 39% of volunteers in the proximal eosphagus correlating to the second segment, i.e., the segment with the lowest amplitude, slope, and velocity of esophageal contractions. The observation that wet swallows have greater amplitudes (P<0.01) and steeper slopes (P<0.05) than dry swallows explains why the occurrence of pill entrapment was reduced when taken with sufficient water. However, even with a water chaser of 120 mL, pill entrapment occurred at the second segment of the esophagus in 1 of 18 volunteers. The observed motility pattern in the proximal eosphagus provides a better explanation for the entrapment of foreign bodies at this site than compression of the esophagus by the left main stem bronchus, aortic arch, or left atrium as suggested by other investigators.     

Manometric characteristics of the pharynx,upper esophageal sphincter,esophagus, and lower esophageal sphincter in patients with oculopharyngeal muscular dystrophy

Improved techniques in esophageal manometry have made this test an attractive option for investigating pharyngeal or esophageal disorders in patients with dysphagia. We studied esophageal as well as upper esophageal sphincter/pharyngeal (UES/P) pressure dynamics in 11 patients with an established diagnosis of oculopharyngeal muscular dystrophy with modern solidstate manometric techniques and then compared manometric and clinical findings. Esophageal manometric abnormalities were found in 10/11 patients, with the most common being simultaneous contractions and incomplete lower esophageal relaxation. 9/11 patients showed abnormal UES/P manometrics, with the most common abnormalities found in the pharynx. The presence of manometric abnormalities closely paralleled clinical assessment of degree of disease severity. Modern manometric techniques offer an opportunity for a quantitative assessment of swallow abnormalities.     

Viscosity measurements of barium sulfate mixtures for use in motility studies of the pharynx and esophagus

Detailed viscosity measurements have been made of barium sulfate mixtures over a wide range of viscosities for use in radiography of the esophagus, stomach, and duodenum. A new methodology was developed for more accurate estimation of viscosity in non-Newtonian fluids in conventional cylinder-type viscometers. As base cases, the variation of viscosity with shear rate was measured for standard commercial mixes of e·z·hd (250% w/v) and a diluted mixture of liquid e·z·paque (40% w/v). These suspensions are strongly shear thinning at low shear rates. Above about 3s⁻¹ the viscosity is nearly constant, but relatively low. To increase the viscosity of the barium sulfate mixture, Knott's strawberry syrup was mixed to different proportions with e·z·hd powder. In this way viscosity was systematically increased to values 130,000 times that of water. For these mixtures the variation of viscosity with temperature, and the change in mixture density with powder-syrup ratio are documented. From least-square fits through the data, simple mathematical formulas are derived for approximate calculation of viscosity as a function of mixture ratio and temperature. These empirical formulas should be useful in the design of “test kits” for systematic study for pharyngeal and esophageal motility, and clinical analysis of motility disorders as they relate to bolus consistency.     

Specializations of the human upper respiratory and upper digestive systems as seen through comparative and developmental anatomy

The human upper respiratory, or aerodigestive, tract serves as the crossroads of our breathing, swallowing and vocalizing pathways. Accordingly, developmental or evolutionary change in any of these functions will, of necessity, affect the others. Our studies have shown that the position in the neck of the mammalian larynx is a major factor in determining function in this region. Most mammals, such as our closest relatives the nonhuman primates, exhibit a larynx positioned high in the neck. This permits an intranarial larynx to be present and creates largely separate respiratory and digestive routes. While infant humans retain this basic mammalian pattern, developmental descent of the larynx considerably alters this configuration. Adult humans have, accordingly, lost separation of the respiratory and digestive routes, but have gained an increased supralaryngeal region of the pharynx which allows for the production of the varied sounds of human speech. How this region has changed during human evolution has been difficult to assess due to the absence of preserved soft-tissue structures. Our studies have shown that the relationship between basicranial shape and laryngeal position in living mammals can be a valuable guide to reconstruct the region in ancestral humans. Based on these findings we have examined the basicrania of fossil ancestors—from over two million years ago to near recent times—and have reconstructed the position of the larynx and pharyngeal region in these early forms. This has allowed us insight into how our ancestors may have breathed and swallowed, and when the anatomy necessary for human speech evolved.