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

Measurement of Muscular Activity Associated With Peristalsis in the Human Gut Using Fiber Bragg Grating Arrays

Author version made available under Publisher copyright policy.Diagnostic catheters based on fibre Bragg gratings (FBG’s) are proving to be highly effective for measurement of the muscular activity associated with peristalsis in the human gut. The primary muscular contractions that generate peristalsis are circumferential in nature; however, it has long been known that there is also a component of longitudinal contractility present, acting in harmony with the circumferential component to improve the overall efficiency of material movement. We report on the development of, and latest results from, catheter based sensors capable of detecting both forms of muscular activity. While detection of the circumferential contractions has been possible using solid state, hydraulic, and pneumatic sensor arrays in the oesophagus and anorectum, FBG based devices allow access into the complex and convoluted regions of the gut below the stomach. We report early results from FBG catheters used during trials of novel therapies in patients with both slow transit constipation and faecal incontinence. In addition, there have been relatively few reports on the measurement or inference of longitudinal contractions in humans. This is due to the lack of a viable recording technique suitable for real-time in-vivo measurement of this type of activity over extended lengths of the gut. We report preliminary data on the detection of longitudinal motion in lengths of excised mammalian colon using an FBG technique that should be viable for similar detection in humans. The longitudinal sensors have been combined with pressure sensing elements to form a composite catheter that allows the relative phase between the two components to be detected. The output of both types of catheter has been validated using digital video mapping in an ex-vivo animal preparation using lengths of rabbit ileum

Pathophysiology of swallowing following oropharyngeal surgery for obstructive sleep apnea syndrome

This article may be used for non-commercial purposes in accordance With Wiley Terms and Conditions for self-archiving'. © 2017 John Wiley & Sons, Inc. All rights reserved. This author accepted manuscript is made available following 12 month embargo from date of publication (Dec 2017) in accordance with the publisher’s archiving policyBackground Uvulopalatopharyngoplasty (UPPP) and coblation channeling of the tongue (CCT) are oropharyngeal surgeries used to treat obstructive sleep apnea syndrome. The extent to which UPPP and CCT affect pharyngeal swallow has not been determined. We therefore conducted a novel case series study employing high‐resolution impedance manometry (HRIM) to quantify the swallowing‐related biomechanics following UPPP and/or CCT surgery. Methods Twelve patients who underwent UPPP+CCT or CCT only were assessed an average 2.5 years postsurgery. Swallow function data were compared with ten healthy controls. All patients completed the Sydney swallow questionnaire (SSQ). Pharyngeal pressure‐flow analysis of HRIM recordings captured key distension, contractility and pressure‐flow timing swallow parameters testing 5, 10, and 20 mL volumes of thin and thick fluid consistencies. Key Results Postoperative patients had more dysphagia symptoms with five returning abnormal SSQ scores. Swallowing was biomechanically altered compared to controls, consistent with diminished swallowing reserve, largely driven by elevated hypopharyngeal intrabolus pressure due to a reduced capacity to open the upper esophageal sphincter to accommodate larger volumes. Conclusions & Inferences Patients who have undergone UPPP and/or CCT surgery appear to have a deficiency in normal modulation of the swallowing mechanism and a reduced swallowing functional reserve. We speculate that these changes may become relevant in later life with the onset of age‐related stressors to the swallowing mechanism. This case series strikes a note of caution that further studies are needed to determine the role of preoperative swallow assessment in patients undergoing UPPP and/or CCT surgery

Mechanisms of Esophago-Pharyngeal Acid Regurgitation in Human Subjects

Esophago-pharyngeal regurgitation is implicated in various otolaryngologic and respiratory disorders. The pathophysiological mechanisms causing regurgitation are still largely unknown