Effect of bolus volume and viscosity on pharyngeal automated impedance manometry variables derived for broad Dysphagia patients.

Automated impedance manometry (AIM) analysis measures swallow variables defining bolus timing, pressure, contractile vigour, and bolus presence, which are combined to derive a swallow risk index (SRI) correlating with aspiration. In a heterogeneous cohort of dysphagia patients, we assessed the impact of bolus volume and viscosity on AIM variables. We studied 40 patients (average age = 46 years). Swallowing of boluses was recorded with manometry, impedance, and videofluoroscopy. AIMplot software was used to derive functional variables: peak pressure (PeakP), pressure at nadir impedance (PNadImp), time from nadir impedance to peak pressure (TNadImp-PeakP), the interval of impedance drop in the distal pharynx (flow interval, FI), upper oesophageal sphincter (UES) relaxation interval (UES RI), nadir UES pressure (Nad UESP), UES intrabolus pressure (UES IBP), and UES resistance. The SRI was derived using the formula SRI = (FI * PNadImp)/(PeakP * (TNadImp-PeakP + 1)) * 100. A total of 173 liquid, 44 semisolid, and 33 solid boluses were analysed. The SRI was elevated in relation to aspiration. PeakP increased with volume. SRI was not significantly altered by bolus volume. PNadImp, UES IBP, and UES resistance increased with viscosity. SRI was lower with increased viscosity. In patients with dysphagia, the SRI is elevated in relation to aspiration, reduced by bolus viscosity, and not affected by bolus volume. These data provide evidence that pharyngeal AIM analysis may have clinical utility for assessing deglutitive aspiration risk to liquid boluses.

A method to objectively assess swallow function in adults with suspected aspiration.

BACKGROUND & AIMS: Pharyngeal manometry and impedance provide information on swallow function. We developed a new analysis approach for assessment of aspiration risk. METHODS: We studied 20 patients (30-95 years old) with suspected aspiration who were referred for videofluoroscopy, along with controls (ages 24-47 years). The pharyngeal phase of liquid bolus swallowing was recorded with manometry and impedance. Data from the first swallow of a bolus and subsequent clearing swallows were analyzed. We scored fluoroscopic evidence of aspiration and investigated a range of computationally derived functional variables. Of these, 4 stood out as having high diagnostic value: peak pressure (PeakP), pressure at nadir impedance (PNadImp), time from nadir impedance to peak pressure (TNadImp-PeakP), and the interval of impedance drop in the distal pharynx (flow interval). RESULTS: During 54 liquid, first swallows and 40 clearing swallows, aspiration was observed in 35 (13 patients). Compared to those of controls, patient swallows were characterized by a lower PeakP, higher PNadImp, longer flow interval, and shorter TNadImp-PeakP. A Swallow Risk Index (SRI), designed to identify dysfunctions associated with aspiration, was developed from iterative evaluations of variables. The average first swallow SRI correlated with the average aspiration score (r = 0.846, P < .00001 for Spearman Rank Correlation). An average SRI of 15, when used as a cutoff, predicted aspiration during fluoroscopy for this cohort (κ = 1.0). CONCLUSIONS: Pressure-flow variables derived from automated analysis of combined manometric/impedance measurements provide valuable diagnostic information. When combined into an SRI, these measurements are a robust predictor of aspiration.

A novel method for the nonradiological assessment of ineffective swallowing.

OBJECTIVES: This validation study evaluates a new manometry impedance-based approach for the objective assessment of pharyngeal function relevant to postswallow bolus residue. METHODS: We studied 23 adult and pediatric dysphagic patients who were all referred for a videofluoroscopy, and compared these patients with 10 adult controls. The pharyngeal phase of swallowing of semisolid boluses was recorded with manometry and impedance. Fluoroscopic evidence of postswallow bolus residue was scored. Pharyngeal pressure impedance profiles were analyzed. Computational algorithms measured peak pressure (Peak P), pressure at nadir impedance (PNadImp), time from nadir impedance to PeakP (PNadImp-PeakP), the duration of impedance drop in the distal pharynx (flow interval), upper esophaghageal sphincter (UES) relaxation interval (UES-RI), nadir UES pressure (NadUESP), UES intrabolus pressure (UES-IBP), and UES resistance. A swallow risk index (SRI) was derived by the formula: SRI=(FI × PNadImp)/(PeakP × (TNadImp-PeakP+1)) × 100. RESULTS: In all, 76 patient swallows (35 with residue) and 39 control swallows (12 with residue) were analyzed. Different functional variables were found to be altered in relation to residue. In both controls and patients, flow interval was longer in relation to residue. In controls, but not patients, residue was associated with an increased PNadImp (suggestive of increased pharyngeal IBP). Controls with residue had increased UES-IBP, NadUESP, and UES resistance compared with patients with residue. Residue in patients was related to a prolonged UES-RI. The SRI was elevated in relation to residue in both controls and patients and an average SRI of 9 was optimally predictive of residue (sensitivity 75% and specificity 80%). CONCLUSIONS: We present novel findings in control subjects and dysphagic patients showing that combined manometry and impedance recordings can be objectively analyzed to derive pressure-flow variables that are altered in relation to the bolus residual and can be combined to predict ineffective pharyngeal swallowing.

Sacrocolpopexy using xenogenic acellular collagen in patients at increased risk for graft-related complications.

AIMS: We studied the long-term anatomical and functional outcome following sacrocolpopexy for apical vaginal prolapse using xenogenic grafts in a population at increased risk for graft-related complications (GRCs). METHODS: Twenty-two consecutive patients with symptomatic apical prolapse were scheduled for laparoscopic sacrocolpopexy (LSC) with porcine grafts because they were presumed to be at risk for GRC, because of pre-existing vaginal ulcerations (n = 4), concomitant vaginal prolapse repair (n = 15), total hysterectomy (n = 1), or intra-operative abdominal contamination due to accidental laceration of the vagina, bowel perforation (n = 1) or the presence of infection (n = 1). Either small intestinal submucosa (n = 8) or dermal collagen (n = 14) was used. Outcome measures were GRCs, anatomical cure (

Short term post-operative morphing of sacrocolpopexy mesh measured by magnetic resonance imaging.

BACKGROUND: Sacrocolpopexy (SC) involves suspension of the vaginal vault or cervix to the sacrum using a mesh. Following insertion, the meshes have been observed to have undergone dimensional changes. OBJECTIVE: To quantify dimensional changes of meshes following implantation and characterize their morphology in-vivo. DESIGN SETTING AND PARTICIPANTS: 24 patients underwent SC using PolyVinyliDeneFluoride mesh loaded with Fe3O4 particles. Tailored anterior and posterior mesh flaps were sutured to the respective vaginal walls, uniting at the apex. The posterior flap continued to the sacrum and was attached there. Meshes were visualized on magnetic resonance (MR) imaging at 12 [3-12] (median [range]) months postoperatively and 3D models of the mesh were generated. Dynamic MR sequences were acquired during valsalva to record mesh mobility. OUTCOME MEASURES: The area of the vagina effectively supported by the mesh (Effective Support Area (ESA)) was calculated. The 3D models' wall thickness map was analyzed to identify the locations of mesh folding. Intraclass correlation (ICC) was calculated to test the reliability of the methods. To measure the laxity and flatness of the mesh, the curvature and the ellipticity of the sacral flap were calculated. RESULTS: The ESA calculation methodology had ICC = 0.97. A reduction of 75.49 [61.55-78.67] % (median [IQR]) in area, 47.64 [38.07-59.81] % in anterior flap, and of 23.95 [10.96-27.21] % in the posterior flap was measured. The mesh appeared thicker near its attachment at the sacral promontory (n = 19) and near the vaginal apex (n = 22). The laxity of the mesh was 1.13 [1.10-1.16] and 60.55 [49.76-76.25] % of the sacral flap was flat. We could not reliably measure mesh mobility (ICC = 0.16). CONCLUSION: A methodology for complete 3D characterization of SC meshes using MR images was presented. After implantation, the supported area is much lower than what is prepared prior to implantation. We propose this happened during the surgery itself.

Characterization of Esophageal Physiology Using Mechanical State Analysis.

The esophagus functions to transport swallowed fluids and food from the pharynx to the stomach. The esophageal muscles governing bolus transport comprise circular striated muscle of the proximal esophagus and circular smooth muscle of the distal esophagus. Longitudinal smooth muscle contraction provides a mechanical advantage to bolus transit during circular smooth muscle contraction. Esophageal striated muscle is directly controlled by neural circuits originating in the central nervous system, resulting in coordinated contractions. In contrast, the esophageal smooth muscle is controlled by enteric circuits modulated by extrinsic central neural connections resulting in neural relaxation and contraction. The esophageal muscles are modulated by sensory information arising from within the lumen. Contraction or relaxation, which changes the diameter of the lumen, alters the intraluminal pressure and ultimately inhibits or promotes flow of content. This relationship that exists between the changes in diameter and concurrent changes in intraluminal pressure has been used previously to identify the "mechanical states" of the circular muscle; that is when the muscles are passively or actively, relaxing or contracting. Detecting these changes in the mechanical state of the muscle has been difficult and as the current interpretation of esophageal motility is based largely upon pressure measurement (manometry), subtle changes in the muscle function during peristalsis can be missed. We hypothesized that quantification of mechanical states of the esophageal circular muscles and the pressure-diameter properties that define them, would allow objective characterization of the mechanisms that govern esophageal peristalsis. To achieve this we analyzed barium swallows captured by simultaneous videofluoroscopy and pressure with impedance recording. From these data we demonstrated that intraluminal impedance measurements could be used to determine changes in the internal diameter of the lumen comparable with measurements from videofluoroscopy. Our data indicated that identification of mechanical state of esophageal muscle was simple to apply and revealed patterns consistent with the known neural inputs activating the different muscles during swallowing.

Bolus Residue Scale: An Easy-to-Use and Reliable Videofluoroscopic Analysis Tool to Score Bolus Residue in Patients with Dysphagia.

Background. We aimed to validate an easy-to-use videofluoroscopic analysis tool, the bolus residue scale (BRS), for detection and classification of pharyngeal retention in the valleculae, piriform sinuses, and/or the posterior pharyngeal wall. Methods. 50 randomly selected videofluoroscopic images of 10 mL swallows (recorded in 18 dysphagia patients and 8 controls) were analyzed by 4 experts and 6 nonexpert observers. A score from 1 to 6 was assigned according to the number of structures affected by residue. Inter- and intrarater reliabilities were assessed by calculation of intraclass correlation coefficients (ICCs) for expert and nonexpert observers. Sensitivity, specificity, and interrater agreement were analyzed for different BRS levels. Results. Intrarater reproducibility was almost perfect for experts (mean ICC 0.972) and ranged from substantial to almost perfect for nonexperts (mean ICC 0.835). Interjudge agreement of the experts ranged from substantial to almost perfect (mean ICC 0.780), but interrater reliability of nonexperts ranged from substantial to good (mean 0.719). BRS shows for experts a high specificity and sensitivity and for nonexperts a low sensitivity and high specificity. Conclusions. The BRS is a simple, easy-to-carry-out, and accessible rating scale to locate pharyngeal retention on videofluoroscopic images with a good specificity and reproducibility for observers of different expertise levels.