Defining Normal Sequential Swallowing Biomechanics

Little is known about the physiology of a common fluid ingestion pattern-sequential swallowing. This study investigated sequential swallowing biomechanics in healthy adults. Archival normative videofluoroscopic swallow studies were analyzed for hyolaryngeal complex (HLC) patterning and biomechanical measures from the first 2 swallows of a 90-mL thin liquid sequential swallow task. The effects of age, sex, HLC type, and swallow order were explored. Eighty-eight participants were included in the primary analyses as they performed sequential swallows. HLC Type I (airway opens, epiglottis approaches baseline) and Type II (airway remains closed, epiglottis remains inverted) most commonly occurred (47% each), followed by Type III (mixed, 6%). Age was significantly associated with Type II and longer hypopharyngeal transit, total pharyngeal transit (TPT), swallow reaction time (SRT), and duration to maximum hyoid elevation. Males demonstrated significantly greater maximum hyoid displacement (Hmax) and longer duration of maximum hyoid displacement. Significantly larger maximum hyoid-to-larynx approximation was linked to the first swallow, while the subsequent swallow had significantly longer oropharyngeal transit, TPT, and SRT. Secondary analyses included an additional 91 participants who performed a series of discrete swallows for the same swallow task. Type II had significantly greater Hmax than Type I and series of discrete swallows. Sequential swallowing biomechanics differ from discrete swallows, and normal variance exists among healthy adults. In vulnerable populations, sequential swallowing may challenge swallow coordination and airway protection. Normative data allow comparison to dysphagic populations. Systematic efforts are needed to further standardize a definition for sequential swallowing.

Diagnosing and managing dysphagia in inclusion body myositis: a systematic review

OBJECTIVES

Dysphagia is a common debilitating clinical feature of IBM. However, the impact of dysphagia in IBM has been historically overlooked. This study aimed to identify, evaluate and summarize the evidence regarding the assessment and management of dysphagia in persons with IBM undergoing treatment.

METHODS

A systematic review was conducted using a multiengine search following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines. Eligible studies had to employ an intervention for persons with IBM, report a swallowing outcome and be published in English. Quality assessments of the eligible studies were performed.

RESULTS

Of 239 studies found, 19 met the inclusion criteria. One study was rated as 'fair' and the rest as 'poor' quality, particularly due to the lack of published and validated swallowing assessment procedures and outcome measures. Cricopharyngeal (CP) dysfunction (12/19) was the most commonly reported swallowing abnormality. Interventions for disease management included pharmacological agents (10/19), followed by surgical (3/19), behavioral (1/19) and combined approaches (5/19). Interventions with immunosuppressants, botulinum toxin injection, balloon dilation and/or CP myotomy led to mixed and transient benefits. Few studies examining statins or behavioral therapies (primarily focused on respiratory function) showed no effects for dysphagia.

CONCLUSION

Various interventions have been reported to temporarily improve dysphagia in persons with IBM. However, these findings are based on limited and overall low-quality evidence. This study cautions against the generalization of these findings and emphasizes the need for further systematic research to improve the diagnosis and management of dysphagia in IBM.

Electrophysiological Measures of Swallowing Functions: A Systematic Review

The purpose of this systematic review was to examine the application of event-related potentials (ERPs) to investigate neural processes of swallowing functions in adults with and without dysphagia. Computerized literature searches were performed from three search engines. Studies were screened using Covidence (Cochrane tool) and followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement standards (PRISMA-2009). A total of 759 studies were initially retrieved, of which 12 studies met inclusion criteria. Electrophysiological measures assessing swallowing functions were identified in two major ERP categories: (1) sensory potentials and (2) pre-motor potentials. Approximately 80% of eligible studies demonstrated strong methodological quality, although most employed a case series or case-control study design. Pharyngeal sensory-evoked potentials (PSEPs) were used to assess pharyngeal afferent cortical processing. The temporal sequence of the PSEP waveforms varied based on the sensory stimuli. PSEPs were delayed with localized scalp maps in patients with dysphagia as compared to healthy controls. The pre-motor ERPs assessed the cortical substrates involved in motor planning for swallowing, with the following major neural substrates identified: pre-motor cortex, supplementary motor area, and primary sensorimotor cortex. The pre-motor ERPs differed in amplitude for the swallow task (saliva versus liquid swallow), and the neural networks differed for cued versus non-cued task of swallowing suggesting differences in cognitive processes. This systematic review describes the application of electrophysiological measures to assess swallowing function and the promising application for furthering understanding of the neural substrates of swallowing. Standardization of protocols for use of electrophysiological measures to examine swallowing would allow for aggregation of study data to inform clinical practice for dysphagia rehabilitation.

Pilot Study of Respiratory-Swallow Coordination in Amyotrophic Lateral Sclerosis

PURPOSE

Amyotrophic lateral sclerosis (ALS) impacts bulbar and respiratory musculature, which may contribute to impaired swallow function (dysphagia) and respiratory-swallow coordination. The purpose of this pilot study was to examine if respiratory-swallow coordination in individuals with ALS was perturbed compared to healthy controls. We further explored relationships between measures of respiratory function and self-reported swallowing outcomes on respiratory-swallow coordination.

METHOD

We employed a cross-sectional design with eight participants with ALS and eight age- and sex-matched healthy participants. Respiratory inductance plethysmography and a nasal cannula were used to capture respiratory-swallow phase patterns during a standardized clinical swallow examination. The advantageous respiratory-swallow phase pattern was defined if exhalation surrounded the swallow (E-E). Spirometry was used to capture indices of respiratory function (forced vital capacity % predicted, peak cough flow [PCF]). Validated questionnaires were used to collect information regarding ALS-related bulbar functional status and swallowing-related concerns.

RESULTS

Compared to the matched healthy cohort, individuals with ALS demonstrated higher rates of non-E-E respiratory-swallow phase patterning and worse bulbar/swallow dysfunction. Group (ALS), swallow tasks, and PCF were significantly associated with respiratory-swallow phase pattern.

CONCLUSIONS

These preliminary findings support altered respiratory-swallow phase patterning in ALS. Future work should employ an instrumental assessment to quantify swallowing physiology and elucidate the relationship between perturbed respiratory-swallow coordination and swallowing function.

Factors Influencing Initiation of Pharyngeal Swallow in Healthy Adults

Purpose The purpose of this study was to investigate factors influencing the initiation of pharyngeal swallow (IPS) in healthy, nondysphagic adults. Method A total of 195 healthy participants ranging in age from 21 to 89 years participated in a modified barium swallow study. IPS was quantified using the Modified Barium Swallow Impairment Profile standardized scoring system across nine swallowing tasks observed in the lateral viewing plane for each participant. Results Large variability for bolus head location at time of hyoid burst (IPS) was observed within this healthy cohort, ranging from the ramus of the mandible to the pyriform sinuses. Significant effects of bolus volume, viscosity, sex, and race were also observed. Conclusion Study findings indicate that IPS is variable in healthy adults and influenced by volume, viscosity, sex, and race. Thus, variability in IPS may be considered typical in otherwise nondysphagic adults. The clinical significance of high Modified Barium Swallow Impairment Profile IPS scores in dysphagic patients, therefore, must be considered within the context of other swallowing impairments. Supplemental Material https://doi.org/10.23641/asha.12735935.

Detailed Vision Screening Results from a Cohort of Individuals with Aphasia

BACKGROUND

Visual functioning is often affected in persons with aphasia following stroke and other brain injuries. Characterizing the visual functioning of persons with aphasia is imperative in both clinical and research domains; however, visual functioning of persons with aphasia is infrequently assessed or described in either domain.

AIMS

This study aims to examine the utility of various visual screening measures as indicated by Hallowell (2008) and document the results of the screening tools for a cohort of persons with aphasia.

METHODS & PROCEDURES

Twenty-three individuals with chronic aphasia completed a detailed vision screening using a visual case history, the Visual Activities Questionnaire, the McDowell Vision Screening, an Amsler grid, the line bisection task, and the National Institute of Health Stroke Scale item 3-visual.

OUTCOMES & RESULTS

Two-thirds of the participants reported significant visual histories with only one participant reporting stroke-related visual deficits. On average, the group rated visual difficulty during daily activities as never or rarely occurring, with the least difficulty reported for color discrimination and the most difficulty with visual acuity and visual search, though still only occurring rarely. All participants passed the cover/uncover screening task measuring ocular alignment and motility, the color perception screening task, and several tasks measuring ocular function. Failing scores, however, were assigned for about half of the participants for distance visual acuity, and only three participants for near visual acuity. Visual fields were normal for about two-thirds of the participants and all participants presented with normal visual attention.

CONCLUSIONS

The results suggest that visual deficits are common in persons with aphasia, but are not necessarily related to the stroke that the person experienced. The results highlight the need to screen the vision of persons with aphasia both for clinical purposes and research protocols to ensure visual deficits are treated, compensated for, or controlled.