Narrow Band Imaging in Flexible Endoscopic Evaluation of Swallowing-How Does It Work?

PURPOSE: The purposes of this study were to compare the visibility of various color groups in different dilutions using narrow band imaging (NBI) and white light (WL) and to determine an optimal color combination using NBI and WL for multicolor flexible endoscopic evaluation of swallowing (FEES), for example, to test different consistencies. METHOD: Preliminary examinations were performed in the oral cavity of two healthy volunteers. Various dyes were tested using NBI and WL to evaluate their visibilities. In the case of a clearly discernible color change, the visibility differences in the dilution series under WL and NBI were recorded and compared. Subsequently, an abbreviated dilution series with NBI and WL was performed in a volunteer as part of a swallow endoscopy to determine whether the results from the oral cavity could be transferred to the hypopharynx. RESULTS: The enhancement of visibility using NBI compared with WL can be proven. When NBI was used, yellow and red food dyes and their mixtures showed distinct color changes. The reacting dyes were still visible under NBI, even at a 10-times-higher dilution, requiring a lower dye concentration for FEES. For increased visibility, the dyes used for FEES with NBI must contain colors from a small range in the yellow and red spectra, which are close to the filter maxima of NBI. Both colors are well visible under WL when combining red and green (secondary color of yellow). CONCLUSIONS: Certain food colorings are visible 10 times more diluted under NBI than under WL. In a multicolored approach, optimal visibility under NBI and WL can be achieved by combining green and red. This new high-sensitivity FEES should be highlighted to allow an instant distinction from WL-FEES; we suggest "FEES+." SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.23280290.

Flexible endoscopic evaluation of swallowing in children with type 1 spinal muscular atrophy.

PURPOSE: This study aimed to report on implementing flexible endoscopic evaluation of swallowing (FEES) in infants and toddlers with type 1 spinal muscular atrophy (SMA). In addition, a comparison of FEES results and clinical scores was carried out. METHODS: A prospective pilot study was conducted including ten symptomatic children with SMA type 1 (two SMN2 copies). They started treatment with one of the three currently approved therapies for SMA at a median age of 3.8 months (range 0.7-8.9). FEES was performed according to a standard protocol using Penetration-Aspiration Scale (PAS) and Murray Secretion Scale as a primary outcome. The Children's Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP-INTEND) for motor function, Neuromuscular Disease Swallowing Status Scale (NdSSS), Oral and Swallowing Abilities Tool (OrSAT), and single clinical swallowing-related parameters were also assessed. RESULTS: Distinct swallowing disorders were already evident in eight children at inclusion. The most common findings from FEES were pharyngeal secretion pooling, penetration, and aspiration of saliva and food as well as delayed initiation of swallowing. Despite an average increase in motor function, no comparable improvement was found in swallowing function. None of the surveyed clinical scores showed a significant dependence on PAS in a mixed linear model. CONCLUSIONS: Valuable information regarding the status of dysphagia can be gathered endoscopically, particularly concerning secretion management and when oral intake is limited. Currently available clinical tools for children with type 1 may represent a change in nutritional status but are not yet mature enough to conclude swallowing ability. Further development is still required.

Implementation of Pediatric Flexible-Endoscopic Evaluation of Swallowing: A Systematic Review and Recommendations for Future Research.

BACKGROUND: Although pediatric flexible-endoscopic evaluation of swallowing (FEES) has developed into a standard in dysphagia diagnostics, there are no valid protocols and procedures for children available to date. OBJECTIVE: This systematic PROSPERO-registered review aimed to identify implementation protocols for pediatric FEES described in research studies, and to analyze them in detail concerning procedural steps, equipment, and reported outcome. METHODS: Included were all studies reporting a pediatric FEES protocol for children aged 0-18 years, if they described at least two criteria defined in advance. The databases MEDLINE and CINHAL were searched systematically from January 2000 to February 2021. Risk of bias for included studies was assessed using the National Institutes of Health (NIH) quality assessment tool for observational cohort and cross-sectional studies. A narrative synthesis of the FEES protocols was conducted and the results compared in tabular form. RESULTS: In total 22 studies were included, reporting on FEES in 1547 infants, children, and adolescents with a wide range of diagnoses. It was possible to identify protocols related to all age groups in general as well as to particular groups such as breastfed or bottle-fed infants. None of the included studies demonstrated a good methodological quality; all studies had missing data. Uniform implementation for sub-groups could not be determined. The reported outcome of FEES examinations could not be compared. DISCUSSION: None of the included studies showed good methodological quality and a significant amount of data were missing; the review still offers a systematic basis for future research to close the serious gap in the area of pediatric FEES. A proposal is made for a minimum requirement for pediatric FEES protocols in scientific studies.

Pediatric Flexible Endoscopic Evaluation of Swallowing: Critical Analysis of Implementation and Future Perspectives.

This study aimed to critically review pediatric swallowing assessment data to determine the future need for standardized procedures. A retrospective analysis of 152 swallowing examinations in 128 children aged 21 days to 18 years was performed. The children were presented at a university dysphagia center between January 2015 and June 2020 for flexible-endoscopic evaluation of swallowing (FEES). Descriptive analysis was conducted for the sample, swallowing pathologies, diagnosis, and missing values. Using binary logistic regression, the relationship between dysphagia and underlying diseases was investigated. The largest group with a common diagnosis in the cohort were children with genetic syndromes (n = 43). Sixty-nine children were diagnosed with dysphagia and 59 without dysphagia. The non-dysphagic group included 15 patients with a behavioral feeding disorder. The presence of an underlying disease significantly increased the chance of a swallowing problem (OR 13.08, 95% CI 3.66 to 46.65, p = .00). In particular, the categories genetic syndrome (OR 2.60, 95% CI 1.15 to 5.88) and neurologic disorder (OR 4.23, 95% CI 1.31 to 13.69) were associated with higher odds for dysphagia. All pediatric FEES were performed without complications, with a completion rate of 96.7%, and with a broad variability of implementation. Several charts lacked information concerning swallowing pathologies, though. Generally, a more standardized protocol and documentation for pediatric FEES is needed to enable better comparability of studies on epidemiology, assessment, and treatment outcomes in future.

The ability of the eating assessment tool-10 to detect penetration and aspiration in Parkinson's disease.

PURPOSE: Dysphagia is common in patients with Parkinson's disease (PD) and often leads to pneumonia, malnutrition, and reduced quality of life. This study investigates the ability of the Eating Assessment Tool-10 (EAT-10), an established, easy self-administered screening tool, to detect aspiration in PD patients. This study aims to validate the ability of the EAT-10 to detect FEES-proven aspiration in patients with PD. METHODS: In a controlled prospective cross-sectional study, a total of 50 PD patients completed the EAT-10 and, subsequently, were examined by Flexible Endoscopic Evaluation of Swallowing (FEES) to determine the swallowing status. The results were rated through the Penetration-Aspiration Scale (PAS) and data were analyzed retrospectively. RESULTS: PAS and EAT-10 did not correlate significantly. Selected items of the EAT-10 could not predict aspiration or residues. 19 (38%) out of 50 patients with either penetration or aspiration were not detected by the EAT-10. The diagnostic accuracy was established at only a sufficient level (AUC 0.65). An optimal cut-off value of ≥ 6 presented a sensitivity of 58% and specificity of 82%. CONCLUSIONS: The EAT-10 is not suited for the detection of penetration and aspiration in PD patients. Therefore, it cannot be used as a screening method in this patient population. There is still a need for a valid, simple, and efficient screening tool to assist physicians in their daily diagnostics and to avoid clinical complications.

Dysphagia Screening in Parkinson's Disease. A diagnostic accuracy cross-sectional study investigating the applicability of the Gugging Swallowing Screen (GUSS).

BACKGROUND: Simple water-swallowing screening tools are not predictive of aspiration and dysphagia in patients with Parkinson's Disease (PD). We investigated the diagnostic accuracy of a multi-texture screening tool, the Gugging Swallowing Screen (GUSS) to identify aspiration and dysphagia/penetration in PD patients compared to flexible endoscopic evaluation of swallowing (FEES). METHODS: Swallowing function was evaluated in 51 PD participants in clinical 'on-medication' state with the GUSS and a FEES examination according to standardized protocols. Inter-rater reliability and convergent validity were determined and GUSS- and FEES-based diet recommendations were compared. KEY RESULTS: Inter-rater reliability of GUSS ratings was high (rs  = 0.8; p < 0.001). Aspiration was identified by the GUSS with a sensitivity of 50%, and specificity of 51.35% (PPV 28%, NPV 73%, LR+ 1.03, LR- 0.97), dysphagia/penetration was identified with 72.97% sensitivity and 35.71% specificity (PPV 75%, NPV 33.33%, LR+ 1.14, LR- 0.76). Agreement between GUSS- and FEES-based diet recommendations was low (rs  = 0.12, p = 0.42) with consistent NPO (Nil per Os) allocation by GUSS and FEES in only one participant. CONCLUSIONS AND INFERENCES: The multi-texture screening tool GUSS in its current form, although applicable with good inter-rater reliability, does not detect aspiration in PD patients with acceptable accuracy. Modifications of the GUSS parameters "coughing," "voice change" and "delayed swallowing" might enhance validity. The GUSS' diet recommendations overestimate the need for oral intake restriction in PD patients and should be verified by instrumental swallowing examination.

Impact of simultaneous subthalamic and nigral stimulation on dysphagia in Parkinson's disease.

OBJECTIVES: Dysphagia is a frequent and highly relevant symptom in Parkinson's disease (PD) due to high associated morbidity and mortality. To compare the effect of simultaneous stimulation of the subthalamic nucleus (STN) and substantia nigra (SNr) with conventional STN-stimulation on swallowing function in Parkinson's disease. METHODS: In this controlled, randomized, double-blind, cross-over clinical trial, 15 PD patients were assessed with DBS switched off (STIM OFF), STN-DBS, STN + SNr-DBS. Patients and 32 age-matched healthy controls were examined clinically and by flexible-endoscopic evaluation of swallowing (FEES) to evaluate the swallowing function. The primary endpoint was the assessment of residues, secondary endpoints were penetration/aspiration, leakage, retained pharyngeal secretions, drooling, and assessments of the patient's self-perception of swallowing on a visual analog scale. RESULTS: Compared with healthy controls PD patients showed significantly more pharyngeal residues in STIM OFF and both DBS modes. Residues or aspiration events were found in 80% of the patients under STN-stimulation. Simultaneous STN + SNr-stimulation had no additional positive effect on objective dysphagia and self-reported swallowing function compared to STN-DBS. INTERPRETATION: Simultaneous STN + SNr-stimulation seems to have no additional beneficial effects on dysphagia when compared with conventional STN-stimulation, but did not deteriorate the swallowing function. If STN + SNr-stimulation is planned to be applied for the improvement of axial symptoms and gait disorders in PD patients, it can be considered safe in terms of dysphagia.

Critical Dysphagia is Common in Parkinson Disease and Occurs Even in Early Stages: A Prospective Cohort Study.

To assess the prevalence of dysphagia and its typical findings in unselected "real-world" Parkinson patients using an objective gold-standard method. This was a prospective, controlled, cross-sectional study conducted in 119 consecutive Parkinson patients of all stages independent of subjective dysphagia. Patients and 32 controls were clinically and endoscopically examined by flexible endoscopic evaluation of swallowing (FEES) to evaluate the deglutition with regard to three consistencies (water, biscuit, and bread). Typical findings of dysphagia like penetration and aspiration, residues, and leakage were assessed. Dysphagia was common in Parkinson patients and occurred in all, even early, disease stages. Only 5% (6/119) of patients showed a completely unremarkable deglutition. Aspiration was seen in 25% (30/119) of patients and always related to water. Residues occurred in 93% (111/119), most commonly for bread. Leakage was much less frequent and was found in only 3-18%, depending on consistency. In a significant fraction of patients, objective dysphagia was not subjectively perceived. A total of 16% of asymptomatic patients suffered from critical aspiration. Significant swallowing deficiencies already occurred in early disease. Aspiration was found in 4 of 20 (20%) patients with disease duration of less than 2 years. Seven of 57 patients (12%) with Hoehn and Yahr stage 2 suffered from severe aspiration. Given the high frequency of critical aspiration in Parkinson disease, these patients should be evaluated early for dysphagia to avoid complications and recommend an adequate therapy. FEES is a simple, cost efficient, minimally invasive method that is ideally suited for this purpose.

Narrow Band Imaging Enhances the Detection Rate of Penetration and Aspiration in FEES.

Narrow band imaging (NBI) is widely used in gastrointestinal, laryngeal, and urological endoscopy. Its original purpose was to visualize vessels and epithelial irregularities. Based on our observation that adding NBI to common white light (WL) improves the contrast of the test bolus in fiberoptic endoscopic evaluation of swallowing (FEES), we now investigated the potential value of NBI in swallowing disorders. 148 FEES images were analyzed from 74 consecutive patients with swallowing disorders, including 74 with and 74 without NBI. All images were evaluated by four dysphagia specialists. Findings were classified according to Rosenbek's penetration-aspiration scale modified for evaluating these FEES images. Intra- and inter-rater reliability was determined as well as observer confidence. A better visualization of the bolus is the main advantage of NBI in FEES. This generally leads to sharper optical contrasts and better detection of small bolus quantities. Accordingly, NBI enhances the detection rate of penetration and aspiration. On average, identification of laryngeal penetration increased from 40 to 73% and of aspiration from 13 to 24% (each p < 0.01) of patients. In contrast to WL alone, the use of NBI also markedly increased the inter- and intra-rater reliability (p < 0.01) and the rating confidence of all experts (p < 0.05). NBI is an easy and cost-effective tool simplifying dysphagia evaluation and shortening FEES evaluation time. It leads to a markedly higher detection rate of pathological findings. The significantly better intra- and inter-rater reliability argues further for a better overall reproducibly of FEES interpretation.