Karen L. Wallace
University of New South Wales
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Gastroenterology | 2000
Karen L. Wallace; Sue Middleton; Ian J. Cook
BACKGROUND & AIMS The aim of this study was to develop and evaluate the validity and reliability of a self-report inventory to measure symptomatic severity of oral-pharyngeal dysphagia. METHODS Test-retest reliability and face, content, and construct validity of a prototype visual analogue scale inventory were assessed in 45 patients who had stable, neuromyogenic dysphagia. RESULTS Normalized scores varied over time by -0.5% +/- 17.6% (95% confidence interval, -9.2% to 8.2%). Factor analysis identified a single factor (dysphagia), to which 18 of 19 questions contributed significantly, that accounted for 56% of total variance (P < 0.0001). After deletion of 2 questions with poor face validity and patient compliance, this proportion increased to 59%; mean test-retest change was -2% (95% confidence interval, -11% to 7%); and total score correlated highly with an independent global assessment severity score (r = 0.7; P < 0.0001). A mean 70% reduction in score (P < 0.0001) was observed after surgery in patients with Zenkers diverticulum (discriminant validity). CONCLUSIONS Applied to patients with neuromyogenic dysphagia, the 17-question inventory shows strong test-retest reliability over 2 weeks as well as face, content, and construct validity. Discriminant validity (responsiveness) has been demonstrated in a population with a correctable, structural cricopharyngeal disorder. Responsiveness of the instrument to treatment in neuromyogenic dysphagia remains to be quantified.
Gastroenterology | 1999
Rohan Williams; Galib N. Ali; Karen L. Wallace; Jeremy S. Wilson; David de Carle; Ian J. Cook
BACKGROUND & AIMS A valid technique for the detection of esophagopharyngeal acid regurgitation would be valuable to evaluate suspected reflux-related otolaryngologic and respiratory disorders. The aim of this study was to derive pH criteria that optimally define esophagopharyngeal acid regurgitation and to examine patterns of regurgitation. METHODS In 19 healthy controls and 15 patients with suspected regurgitation, dual or quadruple pH sensors were used to monitor pharyngeal and esophageal pH. For each combination of the 2 variables, DeltapH and nadir pH, proportions of pH decreases that occurred during or independent of esophageal acidification were calculated to determine the likelihood that an individual pharyngeal pH decrease was a candidate regurgitation event or a definite artifact. RESULTS Overall, 92% of pharyngeal pH decreases of 1-2 pH units and 66% of pH decreases of this magnitude reaching a nadir pH of <4 were artifactual. Optimal criteria defining a pharyngeal acid regurgitation event were a pH decrease that occurred during esophageal acidification, had a DeltapH of >2 units, and reached a nadir of <4 units in less than 30 seconds. Regurgitation occurred more frequently in subjects in an upright (32 of 35) than in a supine (3 of 35 events; P </= 0.0001) position and was more frequently abrupt (synchronous with esophageal acidification) than delayed (P </= 0.05). CONCLUSIONS Accepted criteria for gastroesophageal reflux are not applicable to the detection of esophagopharyngeal acid regurgitation, and most regurgitation occurs abruptly and in upright position.
Dysphagia | 1997
Galib N. Ali; Karen L. Wallace; Tina M. Laundl; David R. Hunt; David J. deCarle; Ian J. Cook
Abstract. 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 pretreatment manometric or radiographic predictors of outcome. Using simultaneous pharyngeal videoradiography and manometry, we studied 20 patients with pharyngeal dysphagia prior to cricopharyngeal diltation (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.
Dysphagia | 1996
Galib N. Ali; Tina M. Laundl; Karen L. Wallace; David J. deCarle; Ian J. Cook
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.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.
Dysphagia | 2004
D. W. Shaw; Rohan Williams; Ian J. Cook; Karen L. Wallace; Martin Weltman; Peter J. Collins; E. Mckay; R. SmartPhD; Maria E. Simula
A valid and reliable technique to quantify the efficiency of the oral–pharyngeal phase of swallowing is needed to measure objectively the severity of dysphagia and longitudinal changes in swallowing in response to intervention. The objective of this study was to develop and validate a scintigraphic technique to quantify the efficiency of bolus clearance during the oral–pharyngeal swallow and assess its diagnostic accuracy. To accomplish this, postswallow oral and pharyngeal counts of residual for technetium-labeled 5- and 10-ml water boluses and regional transit times were measured in 3 separate healthy control groups and in a group of patients with proven oral–pharyngeal dysphagia. Repeat measures were obtained in one group of aged (> 55yr) controls to establish test–retest reliability. Scintigraphic transit measures were validated by comparison with radiographic temporal measures. Scintigraphic measures in those with proven dysphagia were compared with radiographic classification of oral vs. pharyngeal dysfunction to establish their diagnostic accuracy. We found that oral (p = 0.04), but not pharyngeal, isotope clearance is swallowed bolus-dependently. Scintigraphic transit times do not differ from times derived radiographically. All scintigraphic measures have extremely good test–retest reliability. The mean difference between test and retest for oral residual was −1% (95% CI −3%–1%) and for pharyngeal residual it was −2% (95% CI −5%–1%). Scintigraphic transit times have very poor diagnostic accuracy for regional dysfunction. Abnormal oral and pharyngeal residuals have positive predictive values of 100% and 92%, respectively, for regional dysfunction. We conclude that oral–pharyngeal scintigraphic clearance is highly reliable, bolus volume-dependent, and has a high predictive value for regional dysfunction. It may prove useful in assessment of dysphagia severity and longitudinal change.
The American Journal of Gastroenterology | 1999
Rohan Williams; Galib N. Ali; David R. Hunt; Karen L. Wallace; Ian J. Cook
OBJECTIVE:It is not known whether cricopharyngeal myotomy predisposes to esophagopharyngeal regurgitation. Using ambulatory, dual pharyngeal, and esophageal pH monitoring before and after cricopharyngeal myotomy, our aim was to determine the effect, if any, of myotomy on the frequency of esophagopharyngeal acid regurgitation.METHODS:We studied prospectively 18 patients who underwent cricopharyngeal myotomy for pharyngeal dysphagia (10 Zenkers, eight neurogenic dysphagia), of whom 17 agreed to undergo dual pH monitoring preoperatively, and 10 who agreed to both pre- and postoperative monitoring.RESULTS:Symptoms of gastroesophageal reflux disease were present in 30%. Cricopharyngeal myotomy significantly reduced basal upper esophageal sphincter pressure by 49%, from 37 ± 5 mm Hg to 19 ± 3 mm Hg (p= 0.007). Esophagopharyngeal regurgitation was a rare event and the frequency of it did not differ between patients and healthy controls. Preoperatively, three regurgitation events in two patients did not differ from the postoperative frequency of a total of two events in the same two patients.CONCLUSIONS:Increased esophageal acid exposure is common and esophagopharyngeal regurgitation is rare in unselected patients undergoing cricopharyngeal myotomy for pharyngeal dysphagia. Myotomy does not increase the frequency of esophagopharyngeal acid regurgitation in such patients.
American Journal of Physiology-gastrointestinal and Liver Physiology | 1997
Galib N. Ali; Ian J. Cook; Tina M. Laundl; Karen L. Wallace; D. J. de Carle
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.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 midpharyngeal 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.
Gastroenterology | 1996
Galib N. Ali; Karen L. Wallace; Raymond Schwartz; David J. deCarle; Alessandro S. Zagami; Ian J. Cook
American Journal of Physiology-gastrointestinal and Liver Physiology | 1994
Ian J. Cook; M. D. Weltman; Karen L. Wallace; D. W. Shaw; E. Mckay; R. C. Smart; S. P. Butler
American Journal of Physiology-gastrointestinal and Liver Physiology | 2002
Rohan Williams; Karen L. Wallace; Galib N. Ali; Ian J. Cook