The Influence of Orolingual Pressure on the Timing of Pharyngeal Pressure Events

This study explored the influence of two methods of effortful swallow execution on the timing of pharyngeal pressure events. Participants were asked to either emphasize or minimize tongue-to-palate contact during performance of the maneuver. Twenty healthy participants were evaluated using concurrent submental surface electromyography (sEMG), orolingual manometry, and pharyngeal manometry. Each subject performed three repetitions of three counterbalanced tasks (noneffortful dry swallows, effortful dry swallows with tongue-to-palate emphasis, and effortful dry swallows with tongue-to-palate de-emphasis). Four variables were measured: Onset Lag vs. sEMG Peak, Peak Lag vs. sEMG Peak, Total Duration, and Percent Rise Time to Peak. Compared to noneffortful swallows, the effortful swallow task elicited significantly earlier onsets and peaks of pharyngeal pressures relative to the submental sEMG peak. Total pressure event durations were greater and rise times were significantly shorter. When comparing the two methods of effortful swallow execution, a longer latency to peak proximal pharyngeal pressure was found in the tongue-to-palate emphasis condition. These results support the interpretation that the effortful swallow maneuver involves generation of higher velocity bolus driving forces that propel the bolus into and through the pharynx with greater efficiency and that pressure is then sustained to facilitate more complete bolus clearance. Work performed at the Van der Veer Institute for Parkinson’s and Brain Research, Christchurch, New Zealand     

Laryngeal Paralysis: Distinguishing Xth Nerve from Recurrent Nerve Paralysis Through Videoendoscopic Swallowing Study (VESS)

Distinction between unilateral recurrent laryngeal nerve paralysis and Xth nerve paralysis is a rarely addressed issue in the literature. However, it may be crucial to examine the cause of the paralysis and to perform the appropriate investigation. The videoendoscopic swallowing study has been demonstrated to be a useful tool in assessing pharyngeal function. Since in unilateral Xth nerve paralysis the pharynx is impaired on the same side as the vocal fold immobility, it may be easily detected by videoendoscopic swallowing study. The rotation of the posterolateral pharyngeal wall toward the opposite side during swallowing is a sign of impaired motor pharyngeal branches. To demonstrate the usefulness of the videoendoscopic swallowing study in distinguishing unilateral Xth nerve from isolated recurrent nerve paralysis, a series of six patients were studied prospectively. Diagnosis of Xth nerve paralysis focused the investigation toward the high neck or the skull base area. Paralysis of the Xth nerve was suspected in all cases and diagnosis was achieved in five cases by the workup performed. Videoendoscopic swallowing study is a cost-effective and easily available tool which should be performed in all cases of vocal fold paralysis.     

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.     

Morphologic Characteristics of the Superior Pharyngeal Constrictor Muscle in Relation to the Function During Swallowing

To clarify the morphologic characteristics of the superior pharyngeal constrictor muscle, which plays an important role in swallowing, the gross anatomy of the pterygopharyngeal, buccopharyngeal, mylopharyngeal, and glossopharyngeal parts of the muscle was examined. Morphology of the origin of the muscle at the buccopharyngeal part could be divided into three types: type A, membranous morphology from superior to inferior areas; type B, membranous only in superior area; and type C, complete lack of membrane. In all three types, the muscle at the buccopharyngeal part transitionally originated from the buccinator muscle. Morphology of the origin of the muscle at the mylopharyngeal part could be divided into two types: type A, tip of the origin on the mylohyoid line; and type B, tip of the origin away from the mylohyoid line. The present study found that the superior pharyngeal constrictor muscle is attached to the buccinator muscle (which plays an important role in mastication) with mucosa and originates from the mandible and root of the tongue. These findings suggest that the superior pharyngeal constrictor muscle may also play an important role in the expression of smooth coordinated movements associated with ingestion, from mastication to swallowing.     

Swallowing performance in patients with vocal fold motion impairment

Twenty-seven patients with vocal fold motion impairment underwent detailed pharyngoesophagel manometry with a strain gauge assembly linked to a computer recorder. Nine were known to have lesions of the central vagal trunk or nucleus, 9 had recurrent laryngeal nerve (RLN) palsy, and the remainder were idiopathic. The site of the lesion was a more important determinant of subjective swallowing performance than the position of the involved cord at laryngoscopy. Patients with cental lesions had lower tonic and contraction upper esophageal sphincter (UES) pressures than 25 age-matched controls, suggesting that high cervical branches of the lower cranial nerves are important in UES excitatory innervation. RLN palsy patients showed significantly increased pharyngeal contraction amplitude and reduced pharyngoesophageal wave durations. The results suggest that the dysphagia associated with vocal fold motion impairment is not simply due to the disruption of laryngeal deglutitive kinetics, but to independent effects on pharyngeal function.     

The role of cricopharyngeus muscle in pharyngoesophageal disorders

The cricopharyngeus muscle is generally thought to be responsible for the high pressure zone of the pharyngoesophageal (upper esophageal) sphincter. In this review we critically examined the evidence for the role of the cricopharyngeus muscle in the manometric pharyngoesophageal sphincter. The available studies show disparities between the anatomic location of the cricopharyngeus muscle and the manometric high pressure zone of the pharyngoesophageal sphincter. The cricopharyngeus muscle seems to correspond to the distal 1/3 of the sphineteric high pressure zone and the peak high pressure zone appears to be located proximal to the cricopharyngeus muscle. The discrepancy between the upper high pressure zone and the anatomic cricopharyngeus is important in understanding the role of the cricopharyngeus muscle in the pathophysiology and treatment of clinical disorders of the pharyngoesophageal sphincter.This work was supported by National Institute of Diabetes and Digestive and Kidney Diseases Grant DK-31092     

Repetitive contractions of the upper esophageal body and sphincter in achalasia

This report describes repetitive contractions in the upper esophageal sphincter (UES) and the repetitive upper esophageal spontaneous contractions (RUESCs) of patients with achalasia and relates this activity to repetitive contractile activity (RCA) recorded in the more distal esophageal body, to intraesophageal pressure (IEP), and to lower esophageal sphincter (LES) pressure. Two hundred and sixteen consecutive esophageal motility studies from 156 achalasia patients were retrospectively assessed. RUESCs were found in 105 patients (67%) and 125 of 216 studies (58%). General features of the RUESC were (1) coincidence with simultaneous repetitive increases in pressure throughout the entire esophageal body; (2) amplitude of pressure increases tended to be higher in the proximal esophagus; (3) RUESC frequency was different than respiration, except for 6 cases where continuous, RUESC and RCA were synchronized with inspiration; and (4) RUESCs were positively associated with increased IEP, and with increased LES pressure (>40 mmHg). RCA in the esophageal body was uncommon without RUESC. It is concluded that (1) RUESCs are common in achalasia and appear to be closely linked to contractile activity in the upper esophageal body; (2) the close relationship of RUESC and RCA in the esophageal body to increased IEP and elevated LES pressure suggests that esophageal tone is high in these subjects; and (3) these findings indicate a potential mechanism for localization of some of the clinical symptoms to the retrosternal and suprasternal areas, for the inability to readily belch, and for the development of structural features such as a prominent cricopharyngeal bar.