Biomedical subjects

I J Cook

Publications and source records attributed to I J Cook.

At least 19 recordsLinked to original sources

PubMed1997

Predictors of outcome following cricopharyngeal disruption for pharyngeal dysphagia.

The indications for, and predictors of outcome following cricopharyngeal disruption in pharyngeal dysphagia are not clearly defined. Our purpose was to examine the symptomatic response to cricopharyngeal disruption, by either myotomy or dilatation, in patients with oral-pharyngeal dysphagia and to determine pre-treatment manometric or radiographic predictors of outcome. Using simultaneous pharyngeal videoradiography and manometry, we studied 20 patients with pharyngeal dysphagia prior to cricopharyngeal dilatation (n = 11) or myotomy (n = 8), and 23 healthy controls. We measured peak pharyngeal pressure, hypopharyngeal intrabolus pressure, upper esophageal sphincter diameter, and coordination. Response rate to sphincter disruption was 65%. The extent of sphincter opening was significantly reduced in patients compared with controls (p = 0.004), but impaired sphincter opening was not a predictor of outcome. Increased hypopharyngeal intrabolus pressures (> 19 mmHg for 10 ml bolus; > 31 mmHg for 20 ml bolus) was a significant predictor of outcome (p = 0.01). Neither peak pharyngeal pressure nor incoordination were predictors of outcome. In pharyngeal dysphagia, hypopharyngeal intrabolus pressure, and not peak pharyngeal pressure, is a predictor of response to cricopharyngeal disruption. The relationship between intrabolus pressure and impaired sphincter opening is an indirect measure of sphincter compliance which helps predict therapeutic response.

Aged↗

PubMed1997

Influence of altered tongue contour and position on deglutitive pharyngeal and UES function.

The potential influence of altered lingual position and contour during the bolus loading phase of the swallow in mediating the swallowed bolus volume-dependent regulation of upper esophageal sphincter (UES) relaxation and opening was studied in 15 healthy volunteers using simultaneous videoradiography and manometry. A maxillary dental splint modulated tongue deformity during the early oral phase of deglutition. We examined the effect of the splint and swallowed bolus density on bolus volume-dependent changes in the timing of events in the swallow sequence and on hypopharyngeal intrabolus and midpharyngeal pressures. Peak mid-pharyngeal pressure (P = 0.001) and hypopharyngeal intrabolus pressure (P = 0.04) were significantly reduced by the splint. The normal volume-dependent earlier onset of sphincter relaxation and opening was preserved with the splint in situ. The splint significantly delayed the onset of hyoid motion and UES relaxation and opening without influencing transit times or total swallow duration. Alterations in tongue contour and position reduce intrabolus pressure and pharyngeal contraction without influencing normal bolus volume-dependent regulation of timing of UES relaxation and opening.

Adult↗

PubMed1996

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.

Adenoids↗

PubMed1996

Mechanisms of oral-pharyngeal dysphagia in patients with Parkinson's disease.

BACKGROUND & AIMS: Oral-pharyngeal dysphagia in Parkinson's disease is well recognized. The aim of this study was to establish the mechanisms of oral-pharyngeal dysphagia in these patients. METHODS: Using simultaneous videoradiography and pharyngeal manometry, we studied 19 patients with Parkinson's disease (12 with oral-pharyngeal dysphagia and 7 without oral-pharyngeal dysphagia) and compared them with 23 healthy controls. RESULTS: the clinical severity of Parkinson's disease predicted neither the presence nor the severity of dysphagia. Minor alterations in oral function were common in controls and patients, but pharyngeal dysfunction was significantly more prevalent in patients. Incomplete upper esophageal sphincter (UES) relaxation was present in 4 patients (21%), all of whom showed increased hypopharyngeal intrabolus pressure, but not all of whom had a diminished UES opening. The patients had a reduced UES diameter (P = 0.004) and a higher intrabolus pressure compared with the controls (P = 0.007). Pharyngeal contraction pressures were lower in patients, but 6 patients with dysphagia and an abnormal pharyngeal wall motion had normal peak pressures. CONCLUSIONS: An incomplete UES relaxation and a reduced UES opening, both associated with high intrabolus pressure, are prevalent in Parkinson's disease. Oral-pharyngeal dysphagia in Parkinson's disease is multifactorial, with the majority of patients showing oral and pharyngeal dysfunction, even before the clinical expression of dysphagia. Impaired pharyngeal bolus transport is the major determinant of dysphagia.

Aged↗

PubMed1996

Influence of surgery on deglutitive upper oesophageal sphincter mechanics in Zenker's diverticulum.

BACKGROUND/AIMS: To evaluate the role of upper oesophageal sphincter (UOS) compliance in dysphagia, the functional consequences of surgery were evaluated in eight patients with pharyngeal diverticula. The study examined the hypotheses that hypopharyngeal intrabolus pressure is an indicator of UOS compliance and that UOS opening and intrabolus pressure are normalised by surgery. METHODS: In eight patients and nine healthy controls, we measured the timing of swallow events, UOS relaxation, maximal UOS dimensions, intrabolus pressure, and trans-sphincteric bolus flow rates by simultaneous videoradiography and pharyngeal manometry. RESULTS: Bolus flow rates were not changed by surgery. Surgery significantly increased UOS opening (p = 0.0001) and reduced hypopharyngeal intrabolus pressure (p = 0.0001). The slope of the relation between sphincter area and intrabolus pressure was steeper in patients than controls and was normalised by surgery. Surgery had minor effects on basal UOS tone and timing of swallow events. CONCLUSIONS: Upper oesophageal sphincter compliance is poor in Zenker's diverticulum and is normalised by surgery. Hypopharyngeal intrabolus pressure, which correlates with resistance to trans-sphincteric bolus flow, is a useful indicator of UOS compliance. Intrabolus pressure may be a predictor of outcome after myotomy in pharyngeal dysphagia. Cricopharyngeal myotomy is a mandatory component of surgery for Zenker's diverticulum.

Aged↗

PubMed1996

Spontaneous intramural haematoma of the oesophagus: radiologic recognition.

Spontaneous intramural haematoma of the oesophagus (SIHO) is an uncommon disorder. It presents usually with acute chest pain followed by dysphagia. This condition may mimic spontaneous rupture of the oesophagus (Boerhaave Syndrome), dissection of the thoracic aorta or acute myocardial infarction. Hence early accurate confirmation of the diagnosis by radiology is vital for the appropriate acute management. The condition is frequently mistaken for acute myocardial infarction which may prompt inappropriate thrombolytic therapy. The appearances on contrast studies of oesophagus and on CT scanning are characteristic. Despite this, the diagnosis may easily be missed, if appropriate careful radiological technique is not used. This paper reports three consecutive cases of SIHO managed in one institution. These cases illustrate that early gastrografin contrast radiology followed by barium contrast radiology and if necessary by thoracic CT is diagnostic in all cases of this condition.

Aged↗

PubMed1995

Esophageal achalasia and coexistent upper esophageal sphincter relaxation disorder presenting with airway obstruction.

Acute airway obstruction associated with esophageal achalasia is an uncommon but life-threatening complication. The pathophysiology of this phenomenon has not been fully defined. A fully documented case of coexistent esophageal achalasia and upper esophageal sphincter relaxation abnormality presenting with airway obstruction is reported. The patient was initially treated with Heller's myotomy but had a recurrence of respiratory distress. She was successfully treated by cricopharyngeal myotomy. The causes of gas entrapment and respiratory distress are likely to be due to failure of both swallow- and distention-induced upper esophageal sphincter relaxation. Cricopharyngeal myotomy is an effective treatment for this complication, probably by facilitating esophagopharyngeal gas venting.

Aged↗

PubMed1995

Influence of normal aging on oral-pharyngeal and upper esophageal sphincter function during swallowing.

The influence of aging on oral-pharyngeal swallowing was assessed by simultaneous manometry and videoradiography in 14 nondysphagic elderly individuals (mean age 76 yr) and 11 healthy, young controls (mean age 21 yr). Sphincter opening was diminished significantly in the elderly (P = 0.0001), but trans-sphincteric bolus flow rates were preserved. The increased impedance to trans-sphincteric bolus flow from reduced sphincter opening in the aged was reflected in a significant increase in hypopharyngeal intrabolus pressure (P = 0.003). Oral transit time was significantly prolonged in the aged (P = 0.01). The timing of upper esophageal sphincter (UES) manometric relaxation and of opening was significantly delayed in the aged (P = 0.0001), and this delay was comparable in magnitude to the prolongation in oral transit. Coordination of UES relaxation and opening with midpharyngeal contraction was not significantly affected by age. Deglutitive hyolaryngeal motion was not affected by age but was delayed by a duration equivalent to the prolongation in oral transit. We conclude that normal aging prolongs the oral-pharyngeal swallow that impairs UES opening but does not influence pharyngo-sphincteric coordination.

Adolescent↗

PubMed1994

Relationship between sleep patterns and human colonic motor patterns.

BACKGROUND/AIMS: The precise relationships among colonic motor patterns, depth of sleep, and awakening are incompletely understood. The aim of this study was to correlate human colonic motor patterns with sleep stage, nocturnal arousals, and waking. METHODS: We monitored sleep and correlated sleep stage, arousals, and waking with pressures (area under curve and propagating contractions) recorded from the entire colon in 11 healthy volunteers. RESULTS: Propagating contraction frequency (P = 0.01) and area under the curve (P = 0.001) were significantly reduced at night. There was a highly significant correlation between depth of sleep and suppression of area under curve (P = 0.001) and propagating contraction frequency (P = 0.0001). Propagating contractions were eliminated during slow-wave sleep. During rapid eye movement sleep, colonic pressure and propagating contraction frequency increased sharply to levels comparable with those found in stage 2 sleep. Transient arousal from stable sleep, with or without waking, was a potent and immediate stimulus for colonic propagating contractions. CONCLUSIONS: Sleep per se has a profound inhibitory effect on propagating and nonpropagating activity and is the major determinant of diurnal variation of colonic motility. Propagating contractions are eliminated in slow-wave sleep. Rapid eye movement sleep, arousals, and waking have immediate stimulatory effects on colonic motility.

Adolescent↗

PubMed1994

Influence of aging on oral-pharyngeal bolus transit and clearance during swallowing: scintigraphic study.

The aim of the study was to determine the influence of normal aging on regional transit and the efficiency of bolus clearance during the oral and pharyngeal phases of swallowing. We compared scintigraphically derived oral-pharyngeal transit times and isotope clearance during swallowing in 21 healthy aged volunteers (mean age 68 +/- 8 yr) and 9 young controls (mean age 28 +/- 7.5 yr). Subjects swallowed 5- and 10-ml water boluses mixed with 30 MBq 99mtechnetium tin colloid. Oral and pharyngeal transit times, pharyngeal clearance time, and postswallow residual counts in each region were derived from time-activity curves. Pharyngeal residual counts were significantly greater in the aged than in controls (P = 0.0008), but age did not influence oral residual. Aging significantly prolonged oral transit time (P = 0.02), pharyngeal transit time (P = 0.0004), and pharyngeal clearance time (P = 0.0001). We conclude that normal impairs the efficiency of pharyngeal clearance during swallowing, prolongs scintigraphic measures of oral-pharyngeal transit, and increases the exposure time of the glottis to the swallowed bolus.

Adult↗

PubMed1994

Influence of mucosal receptors on deglutitive regulation of pharyngeal and upper esophageal sphincter function.

The potential influence of mucosal sensory receptors on the regulation of oral-pharyngeal swallow events was studied in 15 healthy volunteers using simultaneous videoradiography and manometry. We determined the effects of selective pharyngeal and oral plus pharyngeal anesthesia on the following temporal and manometric measures in response to liquid and viscous swallows: regional transit and clearance times; motion of hyoid and larynx; upper esophageal sphincter relaxation, opening, and closure; and pharyngeal contraction wave characteristics. Under the influence of mucosal anesthesia no subjects demonstrated aspiration during deglutition. Neither regional transit and clearance times nor pharyngosphincteric coordination was influenced significantly by pharyngeal mucosal anesthesia or oral plus pharyngeal anesthesia. Although midpharyngeal and distal pharyngeal contraction amplitudes were not influenced by mucosal anesthesia, midpharyngeal contraction wave duration was reduced significantly by both pharyngeal (P = 0.02) and oral plus pharyngeal anesthesia (P = 0.0005). We conclude that 1) neither elicitation of the pharyngeal swallow response nor temporal regulation among swallow events is dependent on mucosal sensory receptors and 2) duration of the pharyngeal contraction is influenced by sensory input from the oral-pharyngeal mucosa.

Adolescent↗

PubMed1993

Cricopharyngeal function and dysfunction.

The cricopharyngeus is a narrow band of muscle strategically placed between the pharynx and esophagus. Its normal function is vital to the efficient transfer of foodstuffs to the esophagus. Cine- and videoradiography are the major methods of studying the pharyngo-esophageal segment. More recently, refinements in manometric methods have complemented radiology, and have enabled us to achieve a better understanding of cricopharyngeal function in health and disease. Such an understanding of the physical forces necessary for normal bolus transfer, and the recognition of abnormal patterns of pharyngeal and cricopharyngeal motility, will hopefully lead us to a more rational approach to therapy in patients with pharyngeal dysphagia.

Deglutition↗

PubMed1992

Pharyngeal (Zenker's) diverticulum is a disorder of upper esophageal sphincter opening.

Pharyngeal coordination, sphincter opening, and flow pressures during swallowing were investigated in patients with pharyngeal (Zenker's) diverticula. Fourteen patients with diverticula and 9 healthy age-matched controls were studied using simultaneous videoradiography and manometry. Pharyngeal and upper esophageal sphincter pressures were recorded by a perfused side hole/sleeve assembly. Temporal relationships among swallowing events, extent of sphincter opening during swallowing, and intrabolus pressure during bolus passage across the sphincter were measured. The timing among pharyngeal contraction and sphincter relaxation, opening, and closure did not differ between patients and controls. Sphincter opening was significantly reduced in patients compared with controls in sagittal (P = 0.0003) and transverse (P = 0.005) planes. Manometric sphincter relaxation was normal in patients. Intrabolus pressure was significantly greater in patients than in controls (P = 0.001). It is concluded that Zenker's diverticulum is a disorder of diminished upper esophageal sphincter opening that is not caused by pharyngosphincteric incoordination or failed sphincter relaxation. Incomplete sphincter opening is likely to cause dysphagia. Increased hypopharyngeal pressures during swallowing are probably important in the pathogenesis of the diverticulum.

Aged↗

PubMed1991

Normal and disordered swallowing: new insights.

Swallowing is a complex sequence of integrated motor events which is programmed entirely within a 'pattern generator', the medullary swallow centre. The swallow is not a reflex but rather a programmed response which is only initiated given the right combination of cortical and peripheral sensory cues to the medulla. Interruption of these afferent pathways profoundly influences the ability to initiate a swallow. While the basic sequence of motor events that constitutes a swallow is constant, the temporal relationships among component events are modifiable according to the characteristics of the swallowed bolus. The pathophysiology of dysphagia can be categorized on the basis of dysfunction of one or more of seven broad mechanisms that make up the swallow: bolus preparation, lubrication, oral delivery, palatal closure, airway closure, pharyngeal propulsion and UOS opening. This mechanistic approach originates directly from the videoradiographic observations and provides a rational basis for treatment. Videoradiography is the single most valuable technique in the evaluation of oral pharyngeal dysphagia. Oesophagoscopy and laryngoscopy should be performed in most cases because small tumours in the region can mimic pharyngeal motor disorders and may be easily overlooked. Manometry is providing valuable physiological and pathophysiological information about swallowing but, as an adjunct to videoradiography, only provides additional important information in the minority of patients undergoing investigation.

Deglutition↗

PubMed1991

Videoradiographic, manometric, and electromyographic analysis of canine upper esophageal sphincter.

We assessed upper esophageal sphincter (UES) function in dogs by concurrent recording of cricopharyngeal electromyographic (EMG) activity, intraluminal pressure, and dimensional changes of the pharyngoesophageal junction at rest and during swallowing. Radial and axial pressure profiles of the UES were determined by continuous pull-through manometry. EMG activity of the cricopharyngeus and thyropharyngeus muscles were correlated with UES pressure under static conditions. We also quantified the temporal relationships among EMG activity of the cricopharyngeus, UES pressure, and pharyngoesophageal junction dimensional changes during swallowing of 2, 4, and 6 ml of barium. When the dogs were prone, the anterior and posterior UES pressures were about twice the lateral pressures and the axial length of the UES was approximately 4 cm. All radial pressures equalized to approximately 20 mmHg when the dogs lay on their sides. The peak pressure zone of the UES corresponded closely with the level of the cricopharyngeal electrode, and resting UES pressure correlated closely with cricopharyngeal but not thyropharyngeal EMG activity. During swallowing, the cricopharyngeus relaxed approximately 200 ms before UES opening and 100 ms before UES relaxation. Superior movement of the hyoid and the larynx was associated temporally with UES relaxation, while anterior movement was associated with UES opening. Increases in bolus volume significantly increased maximal sagittal UES diameter during UES opening but did not alter temporal changes in UES function.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1990

Manometric characteristics of glossopalatal sphincter.

When a liquid bolus is held in the mouth, the posterior tongue and soft palate pinch together to prevent premature spillage of the bolus into the oropharynx. We propose that this glossopalatal closure acts as a glossopalatal sphincter (GPS). In this investigation, we studied glossopalatal closure by obtaining concurrent manometric and radiographic recordings of barium swallows in healthy volunteers. Manometry was done by both a continuous pull through method and also by a stationary catheter technique using a ribbon catheter with multiple sideholes spaced at 1-cm intervals. The results showed that when the mouth was loaded with a fluid bolus, the closed glossopalatal segment generated an asymmetric high-pressure zone with greater pressures toward the tongue and palate than laterally. With swallowing, the glossopalatal sphincter high-pressure zone relaxed and the glossopalatal sphincter opened to allow barium to flow from the mouth into the oropharynx. We conclude that the glossopalatal sphincter functions as a physiological sphincter in that it (1) generates a sustained high-pressure zone and closure when a liquid bolus is held in the mouth and (2) relaxes and opens with swallowing.

Adolescent↗

PubMed1990

Biomechanics of cricopharyngeal bars.

Patients with a prominent cricopharyngeal bar visible on radiography are generally considered to have spasm of the cricopharyngeus, which is the major muscle component of the upper esophageal sphincter. This condition has been termed "cricopharyngeal achalasia." The aim of this study was to determine the pathogenesis of cricopharyngeal bars. Concurrent videofluoroscopic and manometric examinations of the pharynx and upper esophageal sphincter were performed in a cohort of six patients with prominent cricopharyngeal bars and in eight control volunteers. In each subject, swallows of 2-30-mL barium boluses were recorded. The patients with cricopharyngeal bars showed (a) normal peristaltic contraction in the pharynx, (b) normal axial upper esophageal sphincter pressure and relaxation, (c) normal flow rate across the upper esophageal sphincter, and (d) normal duration of upper esophageal sphincter opening for different bolus volumes. The major abnormalities in the patients with cricopharyngeal bars were (a) reduced maximal dimensions of the upper esophageal sphincter during the transsphincteric flow of barium and (b) increased intrabolus pressure upstream to the upper esophageal sphincter. Thus, the increase in intrabolus pressure preserved normal transsphincteric flow rates even though the upper esophageal sphincter did not open normally. Overall, the constellation of findings in the patients studied suggests that the underlying pathogenesis of their cricopharyngeal bar was reduced muscle compliance wherein the relaxed cricopharyngeus did not distend normally during swallowing.

Adult↗

PubMed1990

Effect of dietary fiber on symptoms and rectosigmoid motility in patients with irritable bowel syndrome. A controlled, crossover study.

The aims of this study were to determine (a) whether dietary fiber supplements modify symptoms in patients with irritable bowel syndrome, (b) the effect of fiber on rectosigmoid pressures, and (c) the relationship, if any, between rectosigmoid pressure and symptoms. Fourteen patients entered and 9 completed a double-blind, controlled, cross-over study of 7 mo duration. The mean age was 26 yr (range, 18-37). Patients received 4 cookies daily containing 20 mg corn fiber or placebo. Symptoms and compliance were evaluated monthly. Rectosigmoid pressures and dietary intake were evaluated at the outset and completion of each study arm. Symptoms improved during both fiber and placebo treatments. Those symptoms demonstrating significant improvement with time were pain severity, stool frequency, stool consistency (p = 0.001), number of additional gastrointestinal symptoms present (p = 0.02), and total symptom score (p less than 0.001). Rectosigmoid pressures were not significantly altered by fiber or placebo. Fasting pressures at the distal recording site tended to correlate with pain severity (r = 0.6; p = 0.06). It was concluded that (a) corn fiber and placebo were both effective in alleviating symptoms, (b) there was a correlation between symptom severity and fasting rectosigmoid pressure, and (c) there was a trend toward reduction in fasting and postprandial rectosigmoid pressures after fiber therapy.

Adult↗