Esophagogastric junction distensibility in hiatus hernia.

Hiatus hernia is known to be an important risk factor for developing gastroesophageal reflux disease. We aimed to use the endoscopic functional lumen imaging probe (EndoFLIP) to evaluate the functional properties of the esophagogastric junction. EndoFLIP assessments were made in 30 patients with hiatus hernia and Barrett's esophagus, and in 14 healthy controls. The EndoFLIP was placed straddling the esophagogastric junction and the bag distended stepwise to 50 mL. Cross-sectional areas of the bag and intra-bag pressures were recorded continuously. Measurements were made in the separate sphincter components and hiatus hernia cavity. EndoFLIP measured functional aspects such as sphincter distensibility and pressure of all esophagogastric junction components and visualized all hiatus hernia present at endoscopy. The lower esophageal sphincter in hiatus hernia patients had a lower pressure (e.g. 47.7 ± 13.0 vs. 61.4 ± 19.2 mm Hg at 50-mL distension volume) and was more distensible (all P < 0.001) than the common esophagogastric junction in controls. In hiatus hernia patients, the crural diaphragm had a lower pressure (e.g. 29.6 ± 10.1 vs. 47.7 ± 13.0 mm Hg at 50-mL distension volume) and was more distensible (all P < 0.001) than the lower esophageal sphincter. There was a significant association between symptom scores in patients and EndoFLIP assessment. Conclusively, EndoFLIP was a useful tool. To evaluate the presence of a hiatus hernia and to measure the functional properties of the esophagogastric junction. Furthermore, EndoFLIP distinguished the separate esophagogastric junction components in hiatus hernia patients, and may help us understand the biomechanics of the esophagogastric junction and the mechanisms behind hiatal herniation.

'Endoflip® evaluation of pharyngo-oesophageal segment tone and swallowing in a clinical population: a total laryngectomy case series'.

OBJECTIVES: To evaluate safety of positioning and distending the functional lumen imaging probe in the pharyngo-oesophageal segment in adults with known pharyngo-oesophageal segment dysfunction and to obtain preliminary measurements of pharyngo-oesophageal segment distensibility and opening during swallowing in a clinical group. METHODS: Prospective case series of ten adults post total laryngectomy (61-75 years) recruited from an outpatient ENT clinic. Functional lumen imaging probe was inserted trans-nasally, and the balloon was positioned in the pharyngo-oesophageal segment. Two 20-mL ramp distensions were completed, and subjects performed two dry and two 5-mL and 10-mL liquid swallows at a 12-mL balloon volume. Pharyngo-oesophageal segment distensibility was calculated from cross-sectional area (mm(2) ) and intraballoon pressure (mmHg) measures. During swallowing, extent (mm) and duration (secs) of pharyngo-oesophageal segment opening and intraballoon pressure drop (mmHg) were evaluated. RESULTS: Functional lumen imaging probe could be passed through the pharyngo-oesophageal segment in seven subjects, all of whom completed the protocol. During distensions, pharyngo-oesophageal segment cross-sectional area increased significantly (19.47-148.3 mm(2) , P < 0.001), and intraballoon pressure increased significantly (15- to 20-mL balloon volume, P = 0.005). Pharyngo-oesophageal segment diameter (5.1 mm) increased during dry (7.4 mm), 5-mL (7.3 mm) and 10-mL (7.7 mm) liquid swallows (P = 0.018). Pharyngo-oesophageal segment opening duration varied across dry (1 s), 5-mL (0.8 s) and 10-mL (1.6 s) liquid swallows. Resting intraballoon pressure (25.5 mmHg) did not alter significantly during swallowing (P = 0.656). CONCLUSION: Functional lumen imaging probe provides novel quantitative information regarding pharyngo-oesophageal segment distensibility and opening during swallowing in adults post total laryngectomy. No adverse events were observed in this first clinical study. Data were easy to acquire, and measures may direct candidacy for and establish effectiveness of interventions to alter pharyngo-oesophageal segment tone.

A new evaluation of the upper esophageal sphincter using the functional lumen imaging probe: a preliminary report.

Objective and reliable evaluation of upper esophageal sphincter (UES) opening during swallowing based on videofluoroscopy and pharyngeal manometry challenges dysphagia clinicians. The functional lumen imaging probe (FLIP) is a portable tool based on impedance planimetry originally designed to measure esophogastric junction compliance. It is hypothesized that FLIP can evaluate UES distensibility, and can provide UES diameter and pressure measurements at rest, during swallowing, and during voluntary maneuvers. Eleven healthy adult subjects consented to FLIP evaluation. The probe was inserted transorally, and the balloon was positioned across the UES. Two 20-mL ramp distensions were completed. Changes in UES diameter and intraballoon pressure were measured during dry and 5-mL liquid swallows, and during voluntary swallow postures and maneuvers employed in clinical practice. The protocol was completed by 10 of 11 healthy subjects. Mean intraballoon pressure increased throughout 5-mL (5.8 mmHg; -4.5-18.6 mmHg), 10-mL (8.7 mmHg; 2.3-28.5 mmHg), 15-mL (17.3 mmHg; 9.5-34.8 mmHg), and 20-mL (31.2 mmHg; 16-46.3 mmHg) balloon volumes. Mean resting UES diameter (4.9 mm) increased during dry swallows (9.2 mm) and 5-mL liquid swallows (7.7 mm). Mean UES diameter increased during 5-mL liquid swallows with head turn to right (8.1 mm) and left (8.3 mm), chin tuck (8.4 mm), effortful swallow (8.5 mm), Mendelsohn maneuver (8.1 mm), and supraglottic swallow (7.8 mm). FLIP was safely inserted and distended in the UES, and provided useful quantitative data regarding UES distensibility and UES diameter changes during swallowing maneuvers. Further research is being conducted to explore the role of FLIP in UES evaluation.

Stepwise radiofrequency ablation of Barrett's esophagus preserves esophageal inner diameter, compliance, and motility.

BACKGROUND AND AIM: Stepwise endoscopic circumferential and focal radiofrequency ablation is safe and effective for the eradication of Barrett's esophagus. In contrast to other techniques, radiofrequency ablation appears to avoid significant esophageal scarring or stenosis. Our aim was to evaluate whether radiofrequency ablation has an adverse effect on esophageal function in patients treated for Barrett's esophagus containing intramucosal cancer and/or high-grade dysplasia. METHODS: Twelve patients with Barrett's esophagus containing intramucosal cancer or high-grade dysplasia were included in the study. After endoscopic resection of visible abnormalities, stepwise circumferential and focal ablation were performed every 2 months up to a maximum of five sessions. Measurement of the inner diameter was performed at 1-cm intervals in the distal esophagus. Manometry was performed using a water-perfused sleeve catheter. Compliance was evaluated using the functional lumen imaging probe (FLIP), measuring eight cross-sectional areas within a saline-filled bag with two pressure side holes, one proximal to and one inside the bag. Esophageal sizing, manometry, and compliance were recorded in patients at baseline and at least 2 months after the final ablation session. In addition, FLIP and manometry measurements were performed in 10 healthy volunteers. RESULTS: All patients achieved complete eradication of dysplasia and Barrett's esophagus, without severe complications or ablation-related stenoses. The esophageal diameter was unchanged by the ablation. Lower esophageal sphincter pressure and length and esophageal contraction amplitude before and after ablation were not significantly different. Baseline compliance was significantly different between healthy volunteers and Barrett's esophagus patients. Compliance was not, however, significantly changed by ablation. CONCLUSIONS: Stepwise circumferential and focal ablation of Barrett's esophagus is an effective and safe treatment modality for early Barrett's neoplasia that appears to preserve the functional characteristics of the esophagus.

Measurement of the axial force during primary peristalsis in the oesophagus using a novel electrical impedance technology.

The oesophagus serves to transport food and fluid from the pharynx to the stomach. Oesophageal function is usually evaluated by means of manometry which is a proxy of the force in the radial direction. However, force measurements in the axial direction will provide a better measure of oesophageal transport function. The aim of this study was to develop a probe based on electrical impedance measurements to quantify the axial force generated by oesophageal contractions, i.e. probe elongation was associated with the axial force. Calibration with weights up to 200 g was done. The dispersion, creep, temperature and bending dependence were studied at the bench. Subsequently, the probe was tested in vivo in a healthy human volunteer. The probe showed good reproducibility and the dispersion was <0.04. Some dependence on temperature, creep and bending was found. Interpolation of the calibration curves made it possible to compensate for temperature fluctuations. The maximum deviation was 6.1 +/- 3.7% at loads of 50 g. The influence of creep showed a maximum net creep of 6.1 g after 8 s. The swallowed bolus size correlated with the axial force measurements (P = 0.038) but not with manometric measurements. In conclusion, the new technique measures axial force in the oesophagus and may in the future provide valuable information about oesophageal function.

Three-dimensional biomechanical properties of the human rectum evaluated with magnetic resonance imaging.

A method to evaluate the three-dimensional (3-D) geometry of the human gastrointestinal wall may be valuable for understanding tissue biomechanics, mechano-sensation and function. In this paper we present a magnetic resonance imaging (MRI) based method to determine rectal geometry and validation of data obtained in three volunteers. A specially designed rectal bag was filled in a stepwise manner while MRI and bag pressure were recorded. 3-D models of curvatures, radii of curvature, tension and stress were generated and the circumferential and longitudinal strains were calculated. The computed bag volumes corresponded to the infused volumes. A pronounced bag elongation and decrease in wall thickness was observed during the bag filling. The spatial distributions of the biomechanical parameters were distinctly different between individuals and non-homogeneous throughout the rectal wall due to its complex geometry. The average tension and stress increased as a function of infused volume and circumferential strain. The present study provides a method for characterizing the complex in vivo 3-D geometry of the human rectum. The non-homogenous spatial curvature distribution suggests that simple estimates of tension based on pressure and volume do not reflect the true 3-D biomechanical properties of the rectum.

A new technique for evaluating sphincter function in visceral organs: application of the functional lumen imaging probe (FLIP) for the evaluation of the oesophago-gastric junction.

No quantitative method has been implemented routinely in clinical practice to assess the oesophago-gastric junction (OGJ). Using impedance planimetry a functional lumen imaging probe (FLIP) was constructed to measure eight cross-sectional areas (CSA) at 4 mm intervals inside a saline-filled bag. To validate the FLIP technique for profiling the OGJ, polymethylmethacrylate (Perspex) cylinders with different CSAs were measured ten times by the FLIP to assess reproducibility and accuracy. A geometric sphincter phantom was constructed and its geometry was measured with a 360 degrees radial ultrasound (US) mini-probe pulled through it at a rate of 1 mm s(-1). The measurements were compared with FLIP measurements. Safety and technique reproducibility were tested on a volunteer. Reproducibility and accuracy between the ten samples were good. The probe performed well with and without a balloon mounted on it except for the smallest CSA (38.5 mm(2)) where there was a difference of 22% from the actual value at one CSA measurement point. The FLIP imaged the phantom geometry as well as the radial scanning US mini-probe. Pilot studies on a volunteer showed that the probe could be placed in the OGJ and the balloon distensions revealed the geometry of the sphincter at various levels of distension. The technique may be useful in accessing the role of the OGJ in diseases such as gastroesophageal reflux disease (GORD) and achalasia and their treatments with surgical and endoscopic therapies.

A new measurement of oesophago-gastric junction competence.

Knowledge of the competence of the oesophago-gastric junction (OGJ) is fundamental to the understanding of gastro-oesophageal reflux disease (GORD), a disorder with a high incidence among the general population. A catheter with a bag 9.5 cms long mounted towards the distal end was swallowed by three volunteers. Using manometry readings and the point of respiratory inversion as a guide the probe was placed in the OGJ. The bag was distended with saline at a fixed rate volume before and after the administration of butylscopolamine to block cholinergic-mediated contractile smooth muscle activity. Using impedance planimetry three cross-sectional areas (CSA) measurements were made between three pairs of electrodes with 4 mm between each electrode on the catheter placed inside the ballon. Using the law of Laplace, CSA and pressure data could be calculated to give wall tension. Tension rose in all volunteers as the radius increased and it was higher towards the proximal end of the OGJ indicating that this measurement can be used to show the distensibility of the OGJ at different degrees of opening. This technique could be useful in identifying changes in the competence of the lower oesophageal sphincter in some patients with GORD.

New measures of upper esophageal sphincter distensibility and opening patterns during swallowing in healthy subjects using EndoFLIP®.

BACKGROUND: This paper aims to measure upper esophageal sphincter (UES) distensibility and extent and duration of UES opening during swallowing in healthy subjects using EndoFLIP(®). METHODS: Fourteen healthy subjects (20-50 years) were recruited. An EndoFLIP(®) probe was passed trans-orally and the probe balloon was positioned across the UES. Two 20-mL ramp distensions were completed and UES cross-sectional area (CSA) and intra-balloon pressure (IBP) were evaluated. At 12-mL balloon volume, subjects completed dry, 5- and 10-mL liquid swallows and extent (mm) and duration (s) of UES opening and minimum IBP (mmHg) were analyzed across swallows. KEY RESULTS: Thirteen subjects completed the study protocol. A significant change in UES CSA (P < .001) and IBP (P < .000) was observed during 20-mL distension. UES CSA increased up to 10-mL distension (P < .001), from which point IBP raised significantly (P = 0.004). There were significant changes in UES diameter (mm) (P < .000) and minimum IBP (mmHg) (P < .000) during swallowing events. Resting UES diameter (4.9 mm; IQR 0.02) and minimum IBP (18.8 mmHg; IQR 2.64) changed significantly during dry (9.6 mm; IQR 1.3: P < .001) (3.6 mmHg; IQR 4.1: P = 0.002); 5 mL (8.61 mm; IQR 2.7: P < .001) (4.8 mmHg; IQR 5.7: P < .001) and 10-mL swallows (8.3 mm; IQR 1.6: P < 0.001) (3 mmHg; 4.6: P < .001). Median duration of UES opening was 0.5 s across dry and liquid swallows (P = 0.91). Color contour plots of EndoFLIP(®) data capture novel information regarding pharyngo-esophageal events during swallowing. CONCLUSIONS & INFERENCES: Authors obtained three different types of quantitative data (CSA, IBP, and timing) regarding UES distensibility and UES opening patterns during swallowing in healthy adults using only one device (EndoFLIP(®)). This new measure of swallowing offers fresh information regarding UES dynamics which may ultimately improve patient care.

Evaluation of anal sphincter resistance and distensibility in healthy controls using EndoFLIP ©.

BACKGROUND: Ano-rectal disorders are common in the general population. Although they are not life threatening conditions, they do represent a social stigma and a reduced quality of life for the sufferer. The underlying physiology of muscle function contributing to ano-rectal competence is complex and there is room for a much better understanding so that treatments can improve. METHODS: A cylindrically shaped, liquid filled bag (12 cm long), mounted on a catheter was inserted into the anus and positioned straddling the ano-rectal region in 20 healthy volunteers (10 females). Series of volume-controlled distensions (40 mL min(-1) to 40 mL) were carried out and data on 16 CSA at 5 mm apart and bag pressure were recorded. Provocative tests using squeeze and cough at bag volumes of 20, 30, and 40 mL were carried out. KEY RESULTS: Ramp distension of the anal canal showed that the opening pressure for females (mean, 11 mmHg) was higher than for males (mean, 5 mmHg) (P < 0.001). Geometric profile of the anal canal at low distension volumes showed narrow bands at proximal and distal ends of the anal profile and shortening of a middle narrow zone at higher volumes. Inter-individual differences were observed in the behavior of the proximal end and the distal end of the anal profile during squeeze. CONCLUSIONS & INFERENCES: This distensibility technique provides an important new way of studying the anal canal and hence may have a role in testing sphincter competence in patients with disorders.

A new distensibility technique to measure sphincter of Oddi function.

BACKGROUND: Evaluation of the biliary tract is important in physiological, pathophysiological, and clinical studies. Although the sphincter of Oddi (SO) can be evaluated with manometry, this technique has several limitations. This may explain the difficulties in identifying pathophysiological mechanisms for dysfunction of the SO and in identifying patients who may benefit from certain therapies. To encompass problems with manometry, methods such as the functional lumen imaging probe (FLIP) technique have been developed to study GI sphincters. This study set about miniaturising the FLIP probe and validating it for measurements in the SO. In order to get a better physiological understanding of the SO the aims were to show the sphincter profile in vivo and motility patterns of SO in pilot studies using volunteers that were experiencing biliary type pain but had normal SO manometry. METHODS: The SO probe was constructed to measure eight cross-sectional areas (CSA) along a length of 25 mm inside a saline-filled bag. To validate the technique for profiling the SO, six perspex cylinders with different CSAs were measured nine times to assess reproducibility and accuracy. KEY RESULTS: Reproducibility and accuracy for these measurements were good. The probe performed well in bench tests and was therefore tested in four humans. The data indicated that it was possible to make distensions in the human SO and that a geometric sphincter profile could be obtained. CONCLUSIONS & INFERENCES: The probe will in future studies be tested for diagnostic purposes related to sphincter of Oddi diseases.

Endocinch therapy for gastro-oesophageal reflux disease: a one year prospective follow up.

BACKGROUND: Gastro-oesophageal reflux disease (GORD) is, in the main, treated with either proton pump inhibitor (PPI) drugs or a Nissen fundoplication operation. Recently, BARD developed Endocinch, a device used to place sutures just below the oesophagogastric junction (OGJ) to treat GORD. AIM: To evaluate the long term benefit of the Endocinch technique in patients seen up to 12 months post procedure. PATIENTS: Twenty six patients with symptoms of GORD were recruited and had the procedure performed. Four patients were lost to follow up. METHODS: Twenty two patients completed their one year follow up. Pre procedure and post procedure (up to 12 months) assessments included symptom scoring (DeMeester), upper intestinal endoscopy, oesophageal manometry and 24 hour oesophageal pH, and completion of quality of life (QOL) questionnaires. RESULTS: Mean age was 39 years (range 22-62). Heartburn symptom score was reduced from a mean value of 19.22 at baseline to 7.5 at 12 months (n=22) (p<0.0001). Regurgitation score reduced from a mean of 2.27 at baseline to 0.86 at 12 months (n=22) (p<0.001). Mean (SEM) pH DeMeester acid score was reduced from 44.1 (4.3) to 33.32 (4.73) (p=0.028) at three month post procedure. Percentage upright acid exposure and number of reflux episodes were also reduced significantly. Use of PPIs was reduced by 64% at 12 months post procedure. All QOL assessments showed significant improvement (p=0.01). All transient post procedure complaints resolved within 72 hours. CONCLUSION: The Endocinch procedure is an effective and safe outpatient procedure that offers GORD patients significant improvement in symptomatology, QOL, and reduced requirements for PPIs over at least a one year period.