Pressure flow analysis in the assessment of preswallow pharyngeal bolus presence in dysphagia

Objectives: Preswallow pharyngeal bolus presence is evident in patients with oropharyngeal dysphagia. Pressure flow analysis (PFA) using high resolution manometry with impedance (HRMI) with AIMplot software is a method for objective interpretation of pharyngeal and upper esophageal sphincter (UES) pressures and bolus flow patterns during swallowing. This study aimed to observe alterations in PFA metrics in the event of preswallow pharyngeal bolus presence as seen on videofluoroscopy (VFSS). Methods: Swallows from 40 broad dysphagia patients and 8 controls were recorded with a HRMI catheter during simultaneous VFSS. Evidence of bolus presence and level reached prior to pharyngeal swallow onset was recorded. AIMPlot software derived automated PFA functional metrics. Results: Patients with bolus movement to the pyriform sinuses had a higher SRI, indicating greater swallow dysfunction. Amongst individual metrics, TNadImp to PeakP was shorter and flow interval longer in patient groups compared to controls. A higher pharyngeal mean impedance and UES mean impedance differentiated the two patient groups. Conclusions: This pilot study identifies specific altered PFA metrics in patients demonstrating preswallow pharyngeal bolus presence to the pyriform sinuses. PFA metrics may be used to guide diagnosis and treatment of patients with oropharyngeal dysphagia and track changes in swallow function over time.Lara Ferris, Taher Omari, Margot Selleslagh, Eddy Dejaeger, Jan Tack, Dirk Vanbeckevoort and Nathalie Romme

Automatische Impedantie Manometrie (AIM): objectieve diagnostiek van oro-faryngale dysfagie

Dit overzichtsartikel wil het klinisch potentieel aantonen van Automatische Impedantie Manometrie (AIM) als nieuwe, nietradiologische techniek voor screening en diagnostiek van faryngale dysfagie, zijnde slikstoornissen in de mond, keelholte en bovenste slokdarm. Deze AIM-techniek maakt gebruik van een katheter met druksensoren en impedantie-elektroden om slikken kwantitatief te beschrijven. Een geïntegreerde – eerder dan afzonderlijke – analyse van de gemeten druk- en impedantiepatronen die ontstaan bij het doorslikken van een voedselbolus, kan een zinvolle aanvulling zijn op de dynamische beeldvormingsonderzoeken die vandaag de dag als gouden standaard worden gezien. Belangrijke voordelen zijn het objectieve karakter van de techniek en de geautomatiseerde berekening van diverse slikparameters. Een globale maat voor de slikfunctie kan worden bekomen (Slik Risico Index, SRI) en houdt verband met (de ernst van) het aspiratierisico van de patiënt en de aanwezigheid van bolusresidu. Zo kan een accurate detectie van aspiratie met een sensitiviteit van 0,88 en specificiteit van 0,96 niet via radiologisch onderzoek bereikt worden. Verschillende slikparameters zijn ook voldoende gevoelig om veranderingen in voedselconsistentie te detecteren en om de effecten van slikmanoeuvres objectief te beschrijven. Recent werd ook aangetoond dat deze AIM-analyse snel en betrouwbaar kan worden uitgevoerd door clinici met variërende ervaring en opleiding. Bovendien worden in verschillende patiëntengroepen andere patronen van afwijkende slikparameters aangetroffen. Of deze observatie aanleiding kan geven tot specifieke slikdiagnoses en dus meer gerichte behandelingen is momenteel onderwerp van onderzoek

Objective assessment of swallow function in children with suspected aspiration using pharyngeal automated impedance manometry

OBJECTIVES: The purpose of the present study was to apply a new method, pharyngeal automated impedance manometry (AIM), as an objective assessment tool of swallow function relevant to aspiration, in a cohort of paediatric patients with dysphagia. METHODS: We studied 20 children (mean age 6 years [5 months to 13.4 years]) referred for videofluoroscopy to assess aspiration risk with simultaneous manometry-impedance. Fluoroscopic evidence of aspiration was scored using a validated aspiration-penetration score. Pressure-flow profiles were analysed using AIM analysis measuring peak pressure, pressure at nadir impedance, time from nadir impedance to peak pressure, and flow interval. These variables were combined into a swallow risk index (SRI). RESULTS: Six of 20 children presented with deglutitive aspiration during videofluoroscopic assessment of swallowing. Of 58 liquid swallows analysed, in 9 aspiration was observed. Multiple logistic regression identified longer flow interval (P < 0.05), higher SRI (P < 0.05) and increased pressure in the upper oesophageal sphincter during maximal bolus flow (P < 0.05) to be the dominant risk variables predictive of aspiration in children. Each of these nonradiologically derived pressure-flow variables correlated with higher aspiration scores on videofluoroscopy (P < 0.01). CONCLUSIONS: We present novel, preliminary findings in children with deglutitive aspiration, suggesting that pharyngeal AIM can detect alterations in pressure-flow characteristics of swallowing that predispose to aspiration risk.Nathalie Rommel, Margot Selleslagh, Ilse Hoffman, Maria H. Smet, Geoffrey Davidson, Jan Tack, Taher Imad Omar

Balloon dilation of the esophago-gastric junction affects lower and upper esophageal sphincter function in achalasia

Background: Pneumatic dilation of the lower esophageal sphincter (LES) in achalasia has an unappreciated effect on upper esophageal sphincter (UES) function. We studied UES pressure patterns at baseline and alterations in UES parameters resulting from therapy. Methods: High-resolution manometry (HRM) tracings from 50 achalasia patients, seen at a tertiary center between January 2009 and July 2011, were reviewed. Manometric parameters studied were (i) LES: resting pressure (restP), 4-second integrated relaxation pressure (IRP4); (ii) UES: resting pressure (restP), minimal relaxation pressure (MRP), peak pressure (PP), relaxation interval (RI), intrabolus pressure (IBP), and deglutitive sphincter resistance (DSR). Mixed models analyses with LES and UES parameters as dependent variables and treatment stage as within-subject independent variable of interest were used. Correlations between treatment-induced changes in LES, UES, and esophageal body (EB) parameters were performed. Key Results: Pre- and posttreatment HRM tracings were available from 50 patients (mean age 52.7 ± 18.6 years, 29 men). Upper esophageal sphincter parameters MRP (17.9 ± 1.2 vs 15.2 ± 0.9 mmHg; p = 0.02) and IBP (31.5 ± 1.5 vs 27.4 ± 1.2 mmHg; p = 0.009) were significantly reduced after initial balloon dilation and this effect was significant in type II achalasia (p = 0.002 and p = 0.0006). Peak pressure, RI, and DSR were not. The therapeutic effect on LES IRP4 correlated significantly with the change in UES MRP, statistically mediated by the change in EB deglutitive pressure (p = 0.004 and p = 0.0002). Conclusions & Inferences: We present the first HRM study demonstrating that pneumatic dilation of the LES affects intraesophageal and UES pressures in patients with achalasia.L. Wauters, L. Van Oudenhove, M. Selleslagh, T. Vanuytsel, G. Boeckxstaens, J. Tack, T. Omari and N. Romme

High-resolution manometry combined with impedance measurements discriminates the cause of dysphagia in children

Pressure-flow analysis allows assessing esophageal bolus transport in relation to esophageal pressures. This study aimed to characterize pressure-flow metrics in relation to dysphagia in paediatric patients. We analysed esophageal pressure-impedance recordings of 5 ml liquid and viscous swallows from 35 children (17 M, mean 10.5 ± 0.8 years). Primary indication for referral was gastroesophageal reflux disease (GERD) (9), post-fundoplication dysphagia (5), idiopathic dysphagia (16), trachea-esophageal fistula (2) and other (3). Peristaltic function was assessed using the 20 mmHg iso-contour defect and the timing between bolus pressure and flow was assessed using the Pressure Flow Index, a metric elevated in relation to dysphagia. Patients were stratified in relation to dysphagia and to peristaltic defect size. Dysphagia was characterized by a weaker peristalsis for liquids and higher Pressure Flow Index for viscous. When patients were stratified based on weak or normal peristalsis, dysphagia with weak peristalsis related to a larger iso-contour defect size and dysphagia with normal peristalsis related to higher Pressure Flow Index.Pressure-flow analysis enables differentiation of patients with dysphagia due to weak peristalsis (poor bolus clearance) from abnormal bolus flow resistance (esophageal outflow obstruction). This new dichotomous categorization of esophageal function may help guide the selection of optimal treatment such as pharmacological or endoscopic therapy.• Pressure-flow analysis (PFA) can detect abnormalities in esophageal motility using integrated analysis of bolus propulsion and bolus flow during swallowing. • AIM analysis has recently been reported to be useful in identifying subtle pre-operative esophageal dysfunction in adult patients who developed post-fundoplication dysphagia as well as in patients with non-obstructive dysphagia. What is New: • Pressure-flow parameters can distinguish the cause of dysphagia in paediatric patients. • Combined high-resolution manometry and impedance measurements with pressure-flow analysis can differentiate paediatric patients with dysphagia symptoms in relation to either weak peristalsis (poor bolus clearance) or over-pressurization (abnormal bolus flow resistance). How might it impact on clinical practice in the future? • This study supports the use of a novel objective analysis method on recordings that are readily used in paediatric clinical practice. • The pressure-flow approach allows discriminating esophageal dysfunction in relation to dysphagia symptoms in children. This has not been achieved in children with current analysis methods. • The new findings of this study allow a dichotomous categorization of esophageal function, which may help to guide the selection of the most optimal treatment such as pharmacological or endoscopic therapy.Nathalie Rommel, Taher I. Omari, Margot Selleslagh, Stamatiki Kritas, Charles Cock, Rachel Rosan, Leonel Rodriguez, Samuel Nurk

Whole-body 3D T1-weighted MR imaging in patients with prostate cancer: feasibility and evaluation in screening for metastatic disease.

PURPOSE: To develop and assess the diagnostic performance of a three-dimensional (3D) whole-body T1-weighted magnetic resonance (MR) imaging pulse sequence at 3.0 T for bone and node staging in patients with prostate cancer. MATERIALS AND METHODS This prospective study was approved by the institutional ethics committee; informed consent was obtained from all patients. Thirty patients with prostate cancer at high risk for metastases underwent whole-body 3D T1-weighted imaging in addition to the routine MR imaging protocol for node and/or bone metastasis screening, which included coronal two-dimensional (2D) whole-body T1-weighted MR imaging, sagittal proton-density fat-saturated (PDFS) imaging of the spine, and whole-body diffusion-weighted MR imaging. Two observers read the 2D and 3D images separately in a blinded manner for bone and node screening. Images were read in random order. The consensus review of MR images and the findings at prospective clinical and MR imaging follow-up at 6 months were used as the standard of reference. The interobserver agreement and diagnostic performance of each sequence were assessed on per-patient and per-lesion bases. RESULTS: The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were significantly higher with whole-body 3D T1-weighted imaging than with whole-body 2D T1-weighted imaging regardless of the reference region (bone or fat) and lesion location (bone or node) (P &lt; .003 for all). For node metastasis, diagnostic performance (area under the receiver operating characteristic curve) was higher for whole-body 3D T1-weighted imaging (per-patient analysis; observer 1: P &lt; .001 for 2D T1-weighted imaging vs 3D T1-weighted imaging, P = .006 for 2D T1-weighted imaging + PDFS imaging vs 3D T1-weighted imaging; observer 2: P = .006 for 2D T1-weighted imaging vs 3D T1-weighted imaging, P = .006 for 2D T1-weighted imaging + PDFS imaging vs 3D T1-weighted imaging), as was sensitivity (per-lesion analysis; observer 1: P &lt; .001 for 2D T1-weighted imaging vs 3D T1-weighted imaging, P &lt; .001 for 2D T1-weighted imaging + PDFS imaging vs 3D T1-weighted imaging; observer 2: P &lt; .001 for 2D T1-weighted imaging vs 3D T1-weighted imaging, P &lt; .001 for 2D T1-weighted imaging + PDFS imaging vs 3D T1-weighted imaging). CONCLUSION: Whole-body MR imaging is feasible with a 3D T1-weighted sequence and provides better SNR and CNR compared with 2D sequences, with a diagnostic performance that is as good or better for the detection of bone metastases and better for the detection of lymph node metastases