High-resolution impedance manometry for comparing bolus transit between patients with non-obstructive dysphagia and asymptomatic controls.

BACKGROUND: Currently, there are no high-resolution impedance manometry (HRIM)-based diagnostic criteria for non-obstructive dysphagia (NOD). New impedance parameters, such as the esophageal impedance integral (EII) and volume of inverted impedance (VII) ratios, have shown strong correlations with bolus transit. This study compared the EII and VII ratios as diagnostic tools for NOD. METHODS: We analyzed 36 participants (12 patients with achalasia, 12 patients with NOD [7 with normal motility and 5 with ineffective esophageal motility], and 12 asymptomatic controls) who underwent HRIM with a maximum of 5 swallows per participant. The EII and VII ratios were calculated as Z2 (post-swallow)/Z1 (pre-swallow). Bolus transit was retrospectively evaluated using transluminal impedance analysis. KEY RESULTS: Both EII and VII ratios could effectively distinguish the achalasia group from the non-achalasia groups (area under the receiver operating characteristic curve [AUROC]: 0.83 for VII vs. 0.80 for EII; p = 0.73). However, the VII ratio was significantly better in discriminating asymptomatic controls from patients with dysphagia (NOD + achalasia) (AUROC: 0.81 vs. 0.68; p = 0.01). Moreover, the VII ratio was better in discriminating asymptomatic controls from patients with NOD (AUROC: 0.68 vs. 0.51; p = 0.06). In repeated swallows, the VII ratio was consistently the lowest in controls and the highest in patients with achalasia, whereas the EII ratio did not show a consistent pattern. CONCLUSIONS & INFERENCES: The VII ratio was more reliable than the EII ratio for describing bolus transit and distinguishing patients with NOD from asymptomatic controls, even during repeated measures of subsequent swallows.

Empirical Dilation of Non-obstructive Dysphagia: Current Understanding and Future Directions.

Non-obstructive dysphagia (NOD) is defined as symptomatic dysphagia in patients with negative endoscopic and radiographic workup. The management of NOD remains controversial as there is a discrepancy between different guidelines and clinical practice. Despite the lack of high-quality studies, empiric dilation for NOD is a common clinical practice among endoscopists and the approach varies between different clinical centers. In this review, we summarize the published literature on empiric dilation for NOD and propose a management algorithm for offering empiric dilation to patients presenting with dysphagia.

Solid Swallow Examination During High Resolution Manometry and EGJ-Distensibility Help Identify Esophageal Outflow Obstruction in Non-obstructive Dysphagia.

Single water swallow (SWS) high-resolution manometry (HRM) may miss relevant esophageal motility disorders. Solid test meal (STM) during HRM and lately the functional lumen imaging probe (FLIP) have been shown to be of diagnostic value in the assessment of motility disorders. We aimed to assess the diagnostic yield of STM and FLIP in non-obstructive dysphagia (NOD). Patients assessed for dysphagia with both HRM and FLIP between April 2016 and August 2019 were analyzed for signs of non-obstructive EGJ outflow obstruction (EGJOO) according to Chicago Classification 3.0 (CCv3) and CC adapted for the use with solid swallows (CC-S), followed by an individual group-specific analysis. Five subjects without dysphagia served as control group. Standard HRM- and FLIP-values as well as esophagograms and Eckardt Scores were analyzed. Forty-two patients were identified (male/female, 14/36, median age 62). Twenty-five (59.5%) were diagnosed with EGJOO during STM only (= SWS-negative patients; CC-S). The EGJ distensibility index (EGJ-DI) of symptomatic patients was significantly lower compared to the control group (p = 0.006). EGJ-DI was < 3mm2/mmHg in 67% and 88% of patients diagnosed according to CC-S and CCv3, respectively. The IRP during STM showed a significant association to the corresponding EGJ-DI values (p < 0.001). Seventy-six percent of patients received treatment because of additional STM evaluation with a favorable clinical response rate of 89%. STM and FLIP identify EGJOO in symptomatic patients with normal SWS during HRM. STM resembles an inexpensive and clinically meaningful option to diagnose motility disorders and helps to select patients for interventional treatment.

Efficacy of empiric esophageal dilation in patients with non-obstructive dysphagia: systematic review and meta-analysis.

BACKGROUND AND AIMS: Empiric esophageal dilation is frequently performed for non-obstructive dysphagia. Studies evaluating its efficacy have reported conflicting results. In this meta-analysis, we have evaluated the efficacy of esophageal dilation in the management of non-obstructive dysphagia. METHODS: We reviewed several databases from inception to 26 May 2021 to identify randomized controlled trials (RCTs) and observational studies that evaluated the role of empiric esophageal dilation for non-obstructive dysphagia. Our outcomes of interest were clinical success (improvement in dysphagia after dilation) and difference in post-operative dysphagia score between groups. For categorical variables, we calculated pooled odds ratios (OR) with 95% confidence intervals (CI); for continuous variables, we calculated standardized mean difference (SMD) with 95% CI. Data were analyzed using a random effects model. We used GRADE framework to ascertain the quality of evidence. RESULTS: We included 4 studies (3 RCTs and one observational) with 243 patients; there were 133 treated with empiric dilation and 110 controls. We found no significant difference in clinical success (OR (95% CI) 1.91 (0.89, 4.08)) or post-procedure dysphagia score between groups (SMD (95% CI) 0.38 (-0.37, 1.14)). Our findings remained consistent on subgroup analysis including RCTs only. Quality of evidence ranged from low to very low based on GRADE framework. CONCLUSIONS: Our meta-analysis does not support the use of empiric esophageal dilation in patients with non-obstructive dysphagia. More studies are required to confirm these findings.

High-resolution impedance manometry parameters in the evaluation of esophageal function of non-obstructive dysphagia patients.

BACKGROUND: High-resolution impedance manometry (HRIM) allows evaluation of esophageal bolus retention, flow, and pressurization. We explored novel HRIM measures and assessed their temporal relationship to dysphagia symptoms for boluses of different volume and consistency in non-obstructive dysphagia (NOD) patients. METHODS: Thirty-three NOD patients (n = 19 minor or no disorder of peristalsis ("Normal") and n = 14 esophagogastric junction outflow obstruction ("EGJOO")) were evaluated with HRIM. Patients were administered 5 and 10 mL liquid, semisolid, and 2 and 4 cm solid boluses and indicated bolus perception during individual swallows using a 5-point Likert scale. HRIM was analyzed to assess Chicago Classification and pressure flow metrics, esophageal impedance integral (EII) ratio, and bolus flow time (BFT). KEY RESULTS: Overall, bolus perception increased with increasing bolus consistency (P < 0.001), but did not differ significantly between EGJOO and Normal patients. EGJOO patients had higher IRP4, higher levels of bolus residual (ie, EII ratio and IR), and restricted esophageal emptying. The results for linking semisolid bolus perception to semisolid-derived measures revealed more biomechanically plausible and consistent patterns when compared to those derived for liquid boluses. In Normal patients, perception of boluses of heavier viscosity was related to higher bolus flow resistance during transport, whilst in EGJOO, perception was related to restriction of esophageal emptying. CONCLUSION & INFERENCES: These novel pressure-impedance measures may aid in the evaluation of NOD patients by revealing abnormal motor patterns, which may explain symptom generation. Future studies are needed to evaluate which of these measures are worthy of calculation and to establish protocol settings that allow for their meaningful interpretation.