RESUMO
AUTOMATED IMPEDANCE MANOMETRY (AIM): OBJECTIVE DIAGNOSIS OF OROPHARYNGEAL DYSPHAGIA: This review article aims to demonstrate the clinical potential of Automated Impedance Manometry (AIM) as a new, non-radiological technique for screening and diagnosis of oro-pharyngeal dysphagia. An integrated - rather than separate - analysis of pressure and impedance patterns generated in the pharynx when swallowing a food bolus, can be a useful complement to the radiological investigations considered as gold standard today. Major advantages are the objective nature of this technique and the fully automated calculation of various swallow parameters. A global measure of swallowing function can be derived (a Swallow Risk Index, SRI) and is related to (the severity of) the risk of aspiration and the presence of pharyngeal post-swallow residue. It was shown that aspiration on videofluoroscopy was accurately detected by using AIM with a sensitivity of 0.88 and a specificity of 0.96. AIM analysis can be performed quickly and is reliable in the hands of different end users. Various parameters are sufficiently sensitive to detect changes in bolus consistency and - as was recently found - are influenced by swallowing manoeuvers. Furthermore, different patterns of deviant swallow parameters can be found in different patient populations. Whether this observation can provide specific diagnoses and - as a consequence - more targeted treatments is currently under investigation.
RESUMO
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.
