Correlation of esophageal pressure-flow analysis findings with bolus transit patterns on videofluoroscopy

This is a pre-copyedited, author-produced version of an article accepted for publication in Diseases of the Esophagus following peer review. The version of record Omari TI, Szczesniak MM, Maclean J, Myers JC, Rommel N, Cock C and Cook IJ. Correlation of esophageal pressure-flow analysis findings with bolus transit patterns on videofluoroscopy. Dis Esophagus. 2016 Feb-Mar;29(2):166-73. and is available online at: http://dx.doi.org/10.1111/dote.12300 Copyright © 2017 The International Society for Diseases of the EsophagusPressure-flow analysis quantifies the interactions between bolus transport and pressure generation. We undertook a pilot study to assess the interrelationships between pressure-flow metrics and fluoroscopically determined bolus clearance and bolus transport across the esophagogastric junction (EGJ). We hypothesized that findings of abnormal pressure-flow metrics would correlate with impaired bolus clearance and reduced flow across the EGJ. Videofluoroscopic images, impedance, and pressure were recorded simultaneously in nine patients with dysphagia (62–82 years, seven male) tested with liquid barium boluses. A 3.6 mm diameter solid-state catheter with 25 × 1 cm pressure/12 × 2 cm impedance was utilized. Swallowed bolus clearance was assessed using a validated 7-point radiological bolus transport scale. The cumulative period of bolus flow across the EGJ was also fluoroscopically measured (EGJ flow time). Pressure only parameters included the length of breaks in the 20 mmHg iso-contour and the 4 second integrated EGJ relaxation pressure (IRP4s). Pressure-flow metrics were calculated for the distal esophagus, these were: time from nadir impedance to peak pressure (TNadImp to PeakP) to quantify bolus flow timing; pressure flow index (PFI) to integrate bolus pressurization and flow timing; and impedance ratio (IR) to assess bolus clearance. When compared with controls, patients had longer peristaltic breaks, higher IRs, and higher residual EGJ relaxation pressures (break length of 8 [2, 13] vs. 2 [0, 2] cm, P = 0.027; IR 0.5 ± 0.1 vs. 0.3 ± 0.0, P = 0.019; IRP4s 11 ± 2 vs. 6 ± 1 mmHg, P = 0.070). There was a significant positive correlation between higher bolus transport scores and longer peristaltic breaks (Spearman correlation r = 0.895, P < 0.001) and with higher IRs (r = 0.661, P < 0.05). Diminished EGJ flow times correlated with a shorter TNadImp to PeakP (r = −0.733, P < 0.05) and a higher IR (r = −0.750, P < 0.05). Longer peristaltic breaks and higher IR correlate with failed bolus clearance on videofluoroscopy. The metric TNadImp to PeakP appears to be a marker of the period of time over which the bolus flows across the EGJ

Inter-rater reliability and validity of automated impedance manometry analysis and fluoroscopy in dysphagic patients after head and neck cancer radiotherapy

This article may be used for non-commercial purposes in accordance With Wiley Terms and Conditions for self-archiving'.Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.Introduction: Automated Impedance manometry (AIM) pressure-flow analysis is novel non-radiological method to analyse swallowing function based on impedance-pressure recordings of pharyngeal swallows. In a population of dysphagic head and neck cancer patients, we evaluated the reliability and validity of the AIM-derived swallow risk index (SRI) and a novel measure of post-swallow residue (iZn/Z) by comparing it against videofluoroscopy as the gold standard for assessing aspiration and post-swallow residue risk. Materials and Methods: Three blinded experts classified 88 videofluoroscopic swallows from 16 patients for aspiration and the degree of post-swallow residue using validated videofluroscopy scales. Pressure-impedance recordings of the swallows were also analysed using automated analysis software by one expert and two novice observers who derived the SRI and iZn/Z. Inter-observer concordance for videofluoroscopic and AIM measures was assessed using intraclass correlation coefficients (ICC). Patient SRI and iZn/Z measurements were compared with videofluoroscopy scores and control subjects to determine validity for detecting clinically relevant swallowing dysfunction. . Results: Among individual swallows, agreement among observers assessing presence of penetration and aspiration on videofluoroscopy was modest (ICC 0.57). Agreement among observers for AIM-derived swallow risk index (SRI) and the iZn/Z was good (ICC of 0.71 and ICC of 0.82 respectively). When compared with age-matched controls the SRI was higher in patients with aspiration (mean diff. 28.6, 95% CI [55.85 1.355], p<0.05). The iZn/Z was increased, suggesting greater post-swallow residues, in both patients with aspiration (Δ244 [419.7, 69.52, p<0.05]) and penetration (Δ240 [394.3, 85.77, p<0.05]) compared to controls. Discussion: AIM based measures of swallowing function have better inter-rater reliability than comparable fluoroscopically-derived measures. These measures can be easily determined and are objective markers of clinically relevant features of disordered swallowing following head and neck cancer therapy

Biomechanics of Pharyngeal Deglutitive Function Following Total Laryngectomy

Copyright © 2016 American Academy of Otolaryngology—Head and Neck Surgery Foundation. Reprinted by permission of SAGE PublicationsObjective: Post-laryngectomy surgery, pharyngeal weakness and pharyngoesophageal junction (PEJ) restriction are the underlying candidate mechanisms of dysphagia. We aimed to determine, in laryngectomees whether: 1) hypopharyngeal propulsion is reduced and/or PEJ resistance is increased; 2) endoscopic dilatation improves dysphagia; and 3) if so, whether symptomatic improvement correlate with reduction in resistance to flow across the PEJ. Methods: Swallow biomechanics were assessed in 30 total laryngectomees. Average peak contractile pressure (hPP) and hypopharyngeal intrabolus pressure (hIBP) were measured from combined high resolution manometry and video-fluoroscopic recordings of barium swallows (2, 5&10ml). Patients were stratified into severe dysphagia (Sydney Swallow Questionnaire (SSQ)>500) and mild/nil dysphagia (SSQ≤500). In 5 patients, all measurements were repeated after endoscopic dilatation. Results: Dysphagia was reported by 87%, and 57% had severe and 43% had minor/nil dysphagia. Laryngectomees had lower hPP than controls (110±14mmHg vs 170±15mmHg; p<0.05), while hIBP was higher (29±5mmHg vs 6±5mmHg; p<0.05). There were no differences in hPP between patient groups. However, hIBP was higher in severe than in mild/nil dysphagia (41±10mmHg vs 13±3mmHg; p<0.05). Pre-dilation hIBP (R2=0.97) and its decrement following dilatation (R2=0.98) were good predictors of symptomatic improvement. Conclusion: Increased PEJ resistance is the predominant determinant of dysphagia as it correlates better with dysphagia severity than peak pharyngal contractile pressure. While both baseline PEJ resistance and its decrement following dilatation are strong predictors of outcome following dilatation, the peak pharyngeal pressure is not. PEJ resistance is vital to detect as it is the only potentially reversible component of dysphagia in this context

Resistant starch and exercise independently attenuate weight regain on a high fat diet in a rat model of obesity

<p>Abstract</p> <p>Background</p> <p>Long-term weight reduction remains elusive for many obese individuals. Resistant starch (RS) and exercise may be useful for weight maintenance. The effects of RS, with or without exercise, on weight regain was examined during relapse to obesity on a high carbohydrate, high fat (HC/HF) diet.</p> <p>Methods</p> <p>Obesity-prone rats were fed <it>ad libitum </it>for 16 weeks then weight reduced on a low fat diet to induce a 17% body weight loss (weight reduced rats). Weight reduced rats were maintained on an energy-restricted low fat diet for 18 weeks, with or without a daily bout of treadmill exercise. Rats were then allowed free access to HC/HF diet containing low (0.3%) or high (5.9%) levels of RS. Weight regain, energy balance, body composition, adipocyte cellularity, and fuel utilization were monitored as rats relapsed to obesity and surpassed their original, obese weight.</p> <p>Results</p> <p>Both RS and exercise independently attenuated weight regain by reducing the energy gap between the drive to eat and suppressed energy requirements. Exercise attenuated the deposition of lean mass during relapse, whereas its combination with RS sustained lean mass accrual as body weight returned. Early in relapse, RS lowered insulin levels and reduced the deposition of fat in subcutaneous adipose tissue. Exercise cessation at five weeks of relapse led to increased weight gain, body fat, subcutaneous adipocytes, and decreased lean mass; all detrimental consequences to overall metabolic health.</p> <p>Conclusions</p> <p>These data are the first to show the complimentary effects of dietary RS and regular exercise in countering the metabolic drive to regain weight following weight loss and suggest that exercise cessation, in the context of relapse on a HC/HF diet, may have dire metabolic consequences.</p

Increased Risk of HIV Acquisition among Kenyan Men with Human Papillomavirus Infection

Few data are available concerning the effect of human papillomavirus (HPV) infection on HIV acquisition

A Semantic Information Model for Capturing and Communicating Design Decisions

A semantic information model to improve reuse and communication of engineering design knowledge is presented in this paper. We consider design to be a process involving a sequence of decisions informed by the current state of information. As such, the information model developed is structured to reflect the conceptualizations of engineering design decisions with a particular emphasis on semantically capturing design rationale. Through the approach presented, knowledge reuse is achieved by communicating design rationale. A case study is presented to illustrate two key features of the approach: (1) seamless integration of separate modular domain ontologies and instance knowledge related to engineering design that are needed to support decision making and (2) the explicit documentation of design rationale through design decisions

Human Papillomavirus Detection by Penile Site in Young Men From Kenya

Limited data are available on whether sampling from the penile shaft or urethra increases detection of penile HPV infection in men beyond that found in the glans and coronal sulcus