Frequency and outcomes of gastrostomy insertion in a longitudinal cohort study of atypical parkinsonism.

BACKGROUND: Multiple system atrophy (MSA), progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS) show a high prevalence and rapid progression of dysphagia, which is associated with reduced survival. Despite this, the evidence base for gastrostomy is poor, and the optimal frequency and outcomes of this intervention are not known. We aimed to characterise the prevalence and outcomes of gastrostomy in patients with these three atypical parkinsonian disorders. METHOD: We analysed data from the natural history and longitudinal cohorts of the PROSPECT-M-UK study with up to 60 months of follow-up from baseline. Survival post-gastrostomy was analysed using Kaplan-Meier survival curves. RESULTS: In a total of 339 patients (mean age at symptom onset 63.3 years, mean symptom duration at baseline 4.6 years), dysphagia was present in >50% across all disease groups at baseline and showed rapid progression during follow-up. Gastrostomy was recorded as recommended in 44 (13%) and performed in 21 (6.2%; MSA 7, PSP 11, CBS 3) of the total study population. Median survival post-gastrostomy was 24 months compared with 12 months where gastrostomy was recommended but not done (p = 0.008). However, this was not significant when correcting for age and duration of symptoms at the time of procedure or recommendation. CONCLUSIONS: Gastrostomy was performed relatively infrequently in this cohort despite the high prevalence of dysphagia. Survival post-gastrostomy was longer than previously reported, but further data on other outcomes and clinician and patient perspectives would help to guide use of this intervention in MSA, PSP and CBS.

Dysphagia Assessments as Criteria in the 'Decision-Making Process' for Percutaneous Endoscopic Gastrostomy Placement in People with Amyotrophic Lateral Sclerosis: A Systematic Review.

To review the assessment methods of dysphagia as a criterion for the decision-making process for Percutaneous Endoscopic Gastrostomy (PEG) placement in patients with Amyotrophic Lateral Sclerosis (ALS). Systematic review. A search was conducted in three databases (EMBASE, CINAHL, PUBMED) in December 2022 and updated in July 2023. Two reviewers independently screened, selected, and extracted data. Study quality was appraised using the Joanna Briggs Institute Critical Appraisal Tools. Systematic review registration number in the International Prospective Register of Systematic Reviews (PROSPERO): CRD42022385461. The searches identified 240 records. The 10 eligible studies included 2 case reports, 4 retrospective studies, 3 prospective studies, and 1 cohort observational study. Study quality was low, with most studies having moderate to high risk of bias. Dysphagia is a common criterion for decision-making. Dysphagia assessment is usually in the form of either self-reports, objective instrumental assessments, or both. Dysphagia is a common criterion for the decision-making process, yet is missing in clinical guidelines. Establishing the optimal means of dysphagia assessment is important for timely decision-making procedures, so that life-threatening consequences of dysphagia are minimized.

Developmental Feeding Stages and Their Impact on Child Feeding Behavior.

OBJECTIVES: Previous research has shown that critical periods of feeding skills development exist and feeding problems can arise in children due to delays in attaining feeding developmental milestones. This study aims to delineate the transitional process of feeding development in healthy children and children with gastrointestinal diseases (GIDs) and to examine the relationship between feeding milestones and the appearance of later feeding problems. METHODS: A cross-sectional case-control study among 711 healthy Greek children and 119 children with GID, aged 2-7 years. Parents completed the Greek version of the Behavioral Pediatrics Feeding Assessment Scale and "self-reported" questionnaires assessing child's feeding history. RESULTS: Differences in feeding behavior of preschoolers between the 2 groups were found concerning the time of introduction of complementary (pureed), lumpy, and table foods as well as finger feeding and regular cup-drinking. Age-specific milestones as proposed by guidelines were not reached. Late introduction of complementary and lumpy foods (>6 months and >9 months, respectively) as well as finger feeding (>9 months) were predictive of more problematic feeding behaviors later on. CONCLUSIONS: The trajectory of feeding development, including less studied feeding milestones, both in healthy children and children with GIDs, indicates that there are discrepancies between current feeding practices and infant feeding guidelines, and a tendency to delay the acquisition of all assessed feeding milestones.

Worth a try or a last resort: Healthcare professionals' experiences and opinions of above cuff vocalisation.

BACKGROUND: Above cuff vocalisation (ACV) involves the application of an external flow of air via the subglottic port of a tracheostomy. ACV can facilitate vocalisation and may improve swallowing and quality of life for patients with a tracheostomy. A recent systematic review highlighted the limited evidence available for the acceptability, effectiveness, safety or optimal implementation of ACV. AIMS: To explore the experience of healthcare professionals (HCPs) using ACV and their perceptions of best practice. METHODS AND PROCEDURES: Semi-structured interviews were conducted with a range of HCPs with experience using ACV. Topics included: experiences with ACV, management of ACV, opinions about ACV, impact of COVID-19, future directions for ACV and impact on length of stay. Interviews were conducted online from December 2020 to March 2022. Data were analysed using reflexive thematic analysis. OUTCOMES AND RESULTS: Twenty-four HCPs were interviewed from seven countries and five professional groups. Four interconnected themes were developed: (1) moral distress amplifying the need to fix patients; (2) subjectivity and uncertainty leading to variations in practice and purpose; (3) knowledge and experience leading to control and caution; and (4) worth a try or a last resort. Theme four contained three sub-themes: (a) part of the toolbox; (b) useful but limited tool; and (c) following the patient's lead. The moral distress experienced by HCPs and their essential 'need to fix' patients seems to underpin the varied opinions of ACV. These opinions appear to be formed primarily on the basis of experience, because of the underlying subjectivities and uncertainties. As knowledge and experience with ACV increased, and adverse events were experienced, most HCPs became more cautious in their approach to ACV. CONCLUSIONS AND IMPLICATIONS: More research is needed to reduce the subjectivities and uncertainties surrounding ACV. The implementation of standardised procedures, processes, and competencies may help to reduce the frequency of adverse events and support a more controlled approach. Widening the focus of the purpose of ACV to include swallowing may help to maximise the potential benefits. WHAT THIS PAPER ADDS: What is already known on the subject There is limited and low-quality evidence for above cuff vocalisation (ACV) and clinical application and practice varies substantially. However, the reasons for this variation in practice and healthcare professionals' (HCPs') opinions of ACV were unclear. What this study adds HCPs' experiences and opinions of ACV vary as a result of the uncertainty and subjectivity surrounding ACV compounded by their personal experiences with it. A need for caution also appears to emerge as HCPs become more familiar and experienced with using ACV. What are the clinical implications of this work? Implementing standardised procedures, safety processes and competencies may help to compensate for the uncertainty and subjectivity surrounding ACV and may reduce the frequency of adverse events. Widening the focus of purpose of ACV, including swallowing in addition to communication, may increase the number of potential candidates and increase the potential benefits of ACV. Using multidisciplinary team (MDT) simulation training for ACV competency development might help to improve MDT working and ACV implementation.

Detecting Minor Symptoms of Parkinson's Disease in the Wild Using Bi-LSTM with Attention Mechanism.

Parkinson's disease (PD) is a neurodegenerative disorder characterized by motor and nonmotor impairment with various implications on patients' quality of life. Since currently available therapies are only symptomatic, identifying individuals with prodromal, preclinical, or early-stage PD is crucial, as they would be ideal candidates for future disease-modifying therapies. Our analysis aims to develop a robust model for accurate PD detection using accelerometer data collected from PD and non-PD individuals with mild or no tremor during phone conversations. An open-access dataset comprising accelerometer recordings from 22 PD patients and 11 healthy controls (HCs) was utilized. The data were preprocessed to extract relevant time-, frequency-, and energy-related features, and a bidirectional long short-term memory (Bi-LSTM) model with attention mechanism was employed for classification. The performance of the model was evaluated using fivefold cross-validation, and metrics of accuracy, precision, recall, specificity, and f1-score were computed. The proposed model demonstrated high accuracy (98%), precision (99%), recall (98%), specificity (96%), and f1-score (98%) in accurately distinguishing PD patients from HCs. Our findings indicate that the proposed model outperforms existing approaches and holds promise for detection of PD with subtle symptoms, like tremor, in the wild. Such symptoms can present in the early or even prodromal stage of the disease, and appropriate mobile-based applications may be a practical tool in real-life settings to alert individuals at risk to seek medical assistance or give patients feedback in monitoring their symptoms.

Falls risk is predictive of dysphagia in Parkinson's disease.

OBJECTIVE: Evaluate the relationship between falls, freezing of gait, and swallowing disturbance in Parkinson's disease (PD). BACKGROUND: Dysphagia is a common symptom in PD, and is often thought of as an axial feature along with falls and gait disturbance. It is of interest to examine the relationship between these symptoms in PD, given the possibility of shared pathophysiology due to non-dopaminergic and extranigral dysfunction. METHODS: We recruited 29 consecutive non-demented patients with idiopathic PD and at least one clinically determined impairment in swallowing, falls, or freezing of gait. Swallow dysfunction was assessed using the Swallowing Disturbance Questionnaire (SDQ). The Falls Efficacy Scale and Freezing-of-gait questionnaire were recorded. Correlation analysis and multiple regression were used to determine the relationship between swallow and gait disturbance. RESULTS: Total SDQ score correlated strongly with the falls efficacy scale (Spearman's rho = 0.594; P = 0.001), but not with the freezing-of-gait score. Linear regression controlling for other factors associated with dysphagia identified falls efficacy score as a significant predictor of swallow dysfunction. CONCLUSIONS: The severity of dysphagia in PD is closely related to severity of falls, but not gait freezing. This may be helpful to more precisely determine the anatomical substrate of levodopa-resistant axial symptoms in PD and provide clues to further management.

Determining the Prevalence, Implementation Approaches, and Opinions of Above Cuff Vocalization: A Survey of Health Care Professionals.

OBJECTIVE: To conduct an international survey to investigate the use of above cuff vocalization (ACV) and how practice and opinion differs. DESIGN: Observational, cross-sectional online survey. SETTING: Critical care, acute, rehabilitation, long-term care, and community. PARTICIPANTS: Health care professionals involved in tracheostomy care or weaning (N=243). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Tracheostomy management, prevalence, personal experiences and opinions, and barriers to use. Quantitative data were reported descriptively, and content analysis was conducted with qualitative data. RESULTS: The survey was completed by 243 health care professionals from 9 professional groups and 25 countries, with most responses from the United Kingdom (54%) and speech and language therapists (55%). ACV was used in 39% of services (n=93). Sixty percent (n=50/83) of health care professionals with direct experience of ACV had used it with <10 people. Implementation of ACV varied widely concerning procedures, contraindications, safety processes, professionals involved, competencies, staff training, delivery, and outcome measures. The top benefits were communication (n=76/93; 82%), mood (n=62/93; 67%), and laryngeal sensation (n=49/93; 53%). Complications included discomfort (n=54/93; 58%) and strained vocal quality (n=39/93; 42%). Barriers to ACV implementation included lack of knowledgeable staff (n=92/238; 39%) and lack of access to training (n=73/238; 31%). CONCLUSIONS: ACV uptake varies internationally with no standardized approach to ACV delivery. Diversity of opinions on approaches and benefits exist. Serious complications are infrequent, but minor complications are common. Future research is needed to establish optimal ACV implementation to maximize benefits and minimize risks.

ESSD Commentary on Dysphagia Management During COVID Pandemia.

Since the World Health Organization declared the COVID-19 pandemic a Global Public Health Emergency, experts in swallowing are seeking guidance on service delivery and clinical procedures. The European Society for Swallowing Disorders provides considerations to support experts in swallowing disorders in clinical practice. During the COVID-19 pandemic, assessment and treatment of patients with oropharyngeal dysphagia should be provided, while at the same time balancing risk of oropharyngeal complications with that of infection of patients and healthcare professionals involved in their management. Elective, non-urgent assessment may be temporarily postponed and patients are triaged to decide whether dysphagia assessment is necessary; instrumental assessment of swallowing is performed only if processing of the instruments can be guaranteed and clinical assessment has not provided enough diagnostic information for treatment prescription. Assessment and management of oropharyngeal dysphagia is a high-risk situation as it must be considered an aerosol-generating procedure. Personal protective equipment (PPE) should be used. Telepractice is encouraged and compensatory treatments are recommended.

Number of subjects required in common study designs for functional GABA magnetic resonance spectroscopy in the human brain at 3 Tesla.

Magnetic resonance spectroscopy (MRS) is a research tool for measuring the concentration of metabolites such as γ-aminobutyric acid (GABA) and glutamate in the brain. MEGA-PRESS has been the preferred pulse sequence for GABA measurements due to low physiological GABA concentrations, hence low signal. To compensate, researchers incorporate long acquisition durations (7-10 min) making functional measurements of this metabolite challenging. Here, the acquisition duration and sample sizes required to detect specific concentration changes in GABA using MEGA-PRESS at 3 T are presented for both between-groups and within-session study designs. 75 spectra were acquired during rest using MEGA-PRESS from 41 healthy volunteers in 6 different brain regions at 3 T with voxel sizes between 13 and 22 cm3 . Between-group and within-session variance was calculated for different acquisition durations and power calculations were performed to determine the number of subjects required to detect a given percentage change in GABA/NAA signal ratio. Within-subject variability was assessed by sampling different segments of a single acquisition. Power calculations suggest that detecting a 15% change in GABA using a 2 min acquisition and a 27 cm3 voxel size, depending on the region, requires between 8 and 93 subjects using a within-session design. A between-group design typically requires more participants to detect the same difference. In brain regions with suboptimal shimming, the subject numbers can be up to 4-fold more. Collecting data for longer than 4 min in brain regions examined in this study is deemed unnecessary, as variance in the signal did not reduce further for longer durations.

Cerebellar repetitive transcranial magnetic stimulation restores pharyngeal brain activity and swallowing behaviour after disruption by a cortical virtual lesion.

KEY POINTS: Despite evidence that the human cerebellum has an important role in swallowing neurophysiology, the effects of cerebellar stimulation on swallowing in the disrupted brain have not been explored. In this study, for the first time, the application of cerebellar neurostimulation is characterized in a human model of disrupted swallowing (using a cortical virtual lesion). It is demonstrated that cerebellar stimulation can reverse the suppressed activity in the cortical swallowing system and restore swallowing function in a challenging behavioural task, suggesting the findings may have important therapeutic implications. ABSTRACT: Repetitive transcranial magnetic stimulation (rTMS) can alter neuronal activity within the brain with therapeutic potential. Low frequency stimulation to the 'dominant' cortical swallowing projection induces a 'virtual-lesion' transiently suppressing cortical excitability and disrupting swallowing behaviour. Here, we compared the ability of ipsi-lesional, contra-lesional and sham cerebellar rTMS to reverse the effects of a 'virtual-lesion' in health. Two groups of healthy participants (n = 15/group) were intubated with pharyngeal catheters. Baseline pharyngeal motor evoked potentials (PMEPs) and swallowing performance (reaction task) were measured. Participants received 10 min of 1 Hz rTMS to the pharyngeal motor cortex which elicited the largest PMEPs to suppress cortical activity and disrupt swallowing behaviour. Over six visits, participants were randomized to receive 250 pulses of 10 Hz cerebellar rTMS to the ipsi-lesional side, contra-lesional side or sham while assessing PMEP amplitude or swallowing performance for an hour afterwards. Compared to sham, active cerebellar rTMS, whether administered ipsi-lesionally (P = 0.011) or contra-lesionally (P = 0.005), reversed the inhibitory effects of the cortical 'virtual-lesion' on PMEPs and swallowing accuracy (ipsi-lesional, P < 0.001, contra-lesional, P < 0.001). Cerebellar rTMS was able to reverse the disruptive effects of a 'virtual lesion'. These findings provide evidence for developing cerebellar rTMS into a treatment for post-stroke dysphagia.

Prevalence of drooling, swallowing, and feeding problems in cerebral palsy across the lifespan: a systematic review and meta-analyses.

AIM: To determine the prevalence of drooling, swallowing, and feeding problems in persons with cerebral palsy (CP) across the lifespan. METHOD: A systematic review was conducted using five different databases (AMED, CINAHL, Embase, MEDLINE, and PubMed). The selection process was completed by two independent researchers and the methodological quality of included studies was assessed using the STROBE and AXIS guidelines. Meta-analyses were conducted to determine pooled prevalence estimates of drooling, swallowing, and feeding problems with stratified group analyses by type of assessment and Gross Motor Function Classification System level. RESULTS: A total of 42 studies were included. Substantial variations in selected outcome measures and variables were observed, and data on adults were limited. Pooled prevalence estimates determined by meta-analyses were as high as 44.0% (95% confidence interval [CI] 35.6-52.7) for drooling, 50.4% (95% CI 36.0-64.8) for swallowing problems, and 53.5% (95% CI 40.7-65.9) for feeding problems. Group analyses for type of assessments were non-significant; however, more severely impaired functioning in CP was associated with concomitant problems of increased drooling, swallowing, and feeding. INTERPRETATION: Drooling, swallowing, and feeding problems are very common in people with CP. Consequently, they experience increased risks of malnutrition and dehydration, aspiration pneumonia, and poor quality of life. WHAT THIS PAPER ADDS: Drooling, swallowing, and feeding problems are very common in persons with cerebral palsy (CP). The prevalence of drooling, swallowing, and feeding problems is 44.0%, 50.4%, and 53.5% respectively. There are limited data on the prevalence of drooling, swallowing, and feeding problems in adults. Higher Gross Motor Function Classification System levels are associated with higher prevalence of drooling, swallowing, and feeding problems. There is increased risk for malnutrition, dehydration, aspiration pneumonia, and poor quality of life in CP.

PREVALENCIA DE PROBLEMAS DE SIALORREA, DEGLUCIÓN Y ALIMENTACIÓN EN PARÁLISIS CEREBRAL A LO LARGO DE LA VIDA: UNA REVISIÓN SISTEMÁTICA Y METAANÁLISIS: OBJETIVO: Determinar la prevalencia de problemas de sialorrea/babeo, deglución y alimentación en personas con parálisis cerebral (PC) a lo largo de la vida MÉTODO: Se llevó a cabo una revisión sistemática utilizando cinco bases de datos diferentes (AMED, CINAHL, Embase, MEDLINE y PubMed). El proceso de selección fue completado por dos investigadores independientes y la calidad metodológica de los estudios incluidos se evaluó utilizando las directrices STROBE y AXIS. Se realizó un metaanálisis para determinar las estimaciones de prevalencia agrupadas en problemas de babeo, deglución y alimentación con análisis de grupos estratificados por tipo de evaluación y nivel del Sistema de Clasificación de la Función Motora Gruesa. RESULTADOS: Se incluyeron un total de 42 estudios. Se observaron variaciones sustanciales en las medidas y variables de resultados seleccionadas, y los datos sobre adultos fueron limitados. Las estimaciones de prevalencia agrupadas determinadas por metaanálisis fueron tan altas como 44,0% (intervalo de confianza [IC] del 95% 35,6-52,7) para babeo, 50,4% (IC 95% 36,0-64,8) para problemas de deglución y 53,5 % (IC 95% 40,7-65,9) para problemas de alimentación. Los análisis de grupo para el tipo de evaluaciones no fueron significativos; sin embargo, el funcionamiento más severo en PC se asoció con problemas concomitantes de aumento de sialorrea, deglución y de la alimentación. INTERPRETACIÓN: Problemas relacionados con sialorrea, tragar, y de alimentación son muy comunes en personas con PC. En consecuencia, ellos experimentan mayores riesgos de desnutrición y deshidratación, neumonía por aspiración y mala calidad de vida.

PREVALÊNCIA DE PROBLEMAS COM SIALORRÉIA, DEGLUTIÇÃO E ALIMENTAÇÃO EM PARALISIA CEREBRAL AO LONGO DA VIDA: UMA REVISÃO SISTEMÁTICA E METANÁLISE: OBJETIVO: Determinar a prevalência de problemas com sialorréia, deglutição e alimentação em pessoas com paralisia cerebral (PC) ao longo da vida. MÉTODO: Uma revisão sistemática foi realizada utilizando cinco bases de dados diferentes (AMED, CINAHL, Embase, MEDLINE, e PubMed). O processo de seleção foi realizado por dois pesquisadores independentes e a qualidade metodológica dos estudos incluídos foi avaliada usando as diretrizes STROBE e AXIS. Metanálises foram realizadas para determinar as estimativas de prevalência agrupada de problemas de sialorréia, deglutição e alimentação, com análises estratificadas por tipo de avaliação e nível do Sistema de Classificação da Função Motora Grossa. RESULTADOS: Um total de 42 estudos foram incluídos. Variações substanciais nas medidas de resultado e variáveis selecionadas foram observadas, e dados em adultos são limitados. As estimativas de prevalência agrupada determiadas pela metanálise chegaram a 44,0% (intervalo de confiança [IC] 95% 35,6-52,7) para sialorréia, 50,4% (IC 95% 36,0-64,8) para problemas com deglutição, e 53,5% (IC 95% 40,7-65,9) para problemas de alimentação. Análises agrupadas por tipo de avaliação não foram significativas; no entanto, comprometimento funcional mais severo em PC foi associado com mais problemas concomitantes de salivação deglutição e alimentação. INTERPRETAÇÃO: Problemas de sialorréia, deglutição e alimentação são muito comuns em pessoas com PC. Consequentemente, elas apresentam risco aumentado de malnutrição e desidratação, pneumonia por aspiração e pior qualidade de vida.

Quantification of GABA, glutamate and glutamine in a single measurement at 3 T using GABA-edited MEGA-PRESS.

γ-Aminobutyric acid (GABA) and glutamate (Glu), major neurotransmitters in the brain, are recycled through glutamine (Gln). All three metabolites can be measured by magnetic resonance spectroscopy in vivo, although GABA measurement at 3 T requires an extra editing acquisition, such as Mescher-Garwood point-resolved spectroscopy (MEGA-PRESS). In a GABA-edited MEGA-PRESS spectrum, Glu and Gln co-edit with GABA, providing the possibility to measure all three in one acquisition. In this study, we investigated the reliability of the composite Glu + Gln (Glx) peak estimation and the possibility of Glu and Gln separation in GABA-edited MEGA-PRESS spectra. The data acquired in vivo were used to develop a quality assessment framework which identified MEGA-PRESS spectra in which Glu and Gln could be estimated reliably. Phantoms containing Glu, Gln, GABA and N-acetylaspartate (NAA) at different concentrations were scanned using GABA-edited MEGA-PRESS at 3 T. Fifty-six sets of spectra in five brain regions were acquired from 36 healthy volunteers. Based on the Glu/Gln ratio, data were classified as either within or outside the physiological range. A peak-by-peak quality assessment was performed on all data to investigate whether quality metrics can discriminate between these two classes of spectra. The quality metrics were as follows: the GABA signal-to-noise ratio, the NAA linewidth and the Glx Cramer-Rao lower bound (CRLB). The Glu and Gln concentrations were estimated with precision across all phantoms with a linear relationship between the measured and true concentrations: R1 = 0.95 for Glu and R1 = 0.91 for Gln. A quality assessment framework was set based on the criteria necessary for a good GABA-edited MEGA-PRESS spectrum. Simultaneous criteria of NAA linewidth <8 Hz and Glx CRLB <16% were defined as optimum features for reliable Glu and Gln quantification. Glu and Gln can be reliably quantified from GABA-edited MEGA-PRESS acquisitions. However, this reliability should be controlled using the quality assessment methods suggested in this work.

Using Rasch Analysis to Evaluate the Reliability and Validity of the Swallowing Quality of Life Questionnaire: An Item Response Theory Approach.

The Swallowing Quality of Life questionnaire (SWAL-QOL) is widely used clinically and in research to evaluate quality of life related to swallowing difficulties. It has been described as a valid and reliable tool, but was developed and tested using classic test theory. This study describes the reliability and validity of the SWAL-QOL using item response theory (IRT; Rasch analysis). SWAL-QOL data were gathered from 507 participants at risk of oropharyngeal dysphagia (OD) across four European countries. OD was confirmed in 75.7% of participants via videofluoroscopy and/or fiberoptic endoscopic evaluation, or a clinical diagnosis based on meeting selected criteria. Patients with esophageal dysphagia were excluded. Data were analysed using Rasch analysis. Item and person reliability was good for all the items combined. However, person reliability was poor for 8 subscales and item reliability was poor for one subscale. Eight subscales exhibited poor person separation and two exhibited poor item separation. Overall item and person fit statistics were acceptable. However, at an individual item fit level results indicated unpredictable item responses for 28 items, and item redundancy for 10 items. The item-person dimensionality map confirmed these findings. Results from the overall Rasch model fit and Principal Component Analysis were suggestive of a second dimension. For all the items combined, none of the item categories were 'category', 'threshold' or 'step' disordered; however, all subscales demonstrated category disordered functioning. Findings suggest an urgent need to further investigate the underlying structure of the SWAL-QOL and its psychometric characteristics using IRT.

Repetitive Transcranial Magnetic Stimulation: a Novel Approach for Treating Oropharyngeal Dysphagia.

In recent years, repetitive transcranial magnetic stimulation, a technique used to produce human central neurostimulation, has attracted increased interest and been applied experimentally in the treatment of dysphagia. This review presents a synopsis of the current research for the application of repetitive transcranial magnetic stimulation (rTMS) on dysphagia. Here, we review the mechanisms underlying the effects of rTMS and the results from studies on both healthy volunteers and dysphagic patients. The clinical studies on dysphagia have primarily focussed on dysphagia post-stroke. We discuss why it is difficult to draw conclusions for the efficacy of this neurostimulation technique, given the major differences between studies. The intention here is to stimulate potential research questions not yet investigated for the application of rTMS on dysphagic patients prior to their translation into clinical practice for dysphagia rehabilitation.

A Longitudinal Study of Symptoms of Oropharyngeal Dysphagia in an Elderly Community-Dwelling Population.

Dysphagia has been estimated to affect around 8-16 % of healthy elderly individuals living in the community. The present study investigated the stability of perceived dysphagia symptoms over a 3-year period and whether such symptoms predicted death outcomes. A population of 800 and 550 elderly community-dwelling individuals were sent the Sydney Swallow Questionnaire (SSQ) in 2009 and 2012, respectively, where an arbitrary score of 180 or more was chosen to indicate symptomatic dysphagia. The telephone interview cognitive screen measured cognitive performance and the Geriatric Depression Scale measured depression. Regression models were used to investigate associations with dysphagia symptom scores, cognition, depression, age, gender and a history of stroke; a paired t test was used to examine if individual mean scores had changed. A total of 528 participants were included in the analysis. In 2009, dysphagia was associated with age (P = 0.028, OR 1.07, CI 1.01, 1.13) and stroke (P = 0.046, OR 2.04, CI 1.01, 4.11) but these associations were no longer present in 2012. Those who had symptomatic dysphagia in 2009 (n = 75) showed a shift towards improvement in swallowing (P < 0.001, mean = -174.4, CI -243.6, -105.3), and for those who died from pneumonia, there was no association between the SSQ derived swallowing score and death (P = 0.509, OR 0.10, CI -0.41, -0.20). We conclude that swallowing symptoms are a temporally dynamic process, which increases our knowledge on swallowing in the elderly.

High-frequency focal repetitive cerebellar stimulation induces prolonged increases in human pharyngeal motor cortex excitability.

KEY POINTS: Neurostimulation is a rapidly emerging approach to swallowing rehabilitation, but cerebellar stimulation has not been explored as a treatment. Such proposed therapies for post-stroke dysphagia have required confirmation of physiological effects and optimisation of parameters in healthy humans prior to translational progression into patient groups. There is strong evidence for a role of the cerebellum in swallowing physiology, but this relationship has been under-explored. Recently, single pulses of cerebellar magnetic stimulation have been shown to directly evoke responses from pharyngeal musculature and produce short-term enhancement of cortico-pharyngeal motor evoked potentials, suggesting the feasibility of a cerebellar approach to neurostimulation in the swallowing system. We therefore examined multiple parameters of repetitive cerebellar magnetic stimulation and have described the optimal settings to provoke longer-lasting changes in swallowing neurophysiology. Based on evidence from the post-stroke dysphagia neurostimulation literature, these changes may have a therapeutic potential for swallowing rehabilitation. ABSTRACT: Brain neurostimulation has been shown to modulate cortical swallowing neurophysiology in post-stroke dysphagia with therapeutic effects which are critically dependent on the stimulation parameters. Cerebellar neurostimulation is, however, a novel, unexplored approach to modulation of swallowing pathways as a prelude to therapy for dysphagia. Here, we randomised healthy human subjects (n = 17) to receive one of five cerebellar repetitive TMS (rTMS) interventions (Sham, 1 Hz, 5 Hz, 10 Hz and 20 Hz) on separate visits to our laboratory. Additionally, a subset of subjects randomly received each of three different durations (50, 250, 500 pulses) of optimal frequency versus sham cerebellar rTMS. Prior to interventions subjects underwent MRI-guided single-pulse transcranial magnetic stimulation (TMS) to co-localise pharyngeal and thenar representation in the cortex and cerebellum (midline and hemispheric) before acquisition of baseline motor evoked potential (MEP) recordings from each site as a measure of excitability. Post-interventional MEPs were recorded for an hour and compared to sham using repeated measures ANOVA. Only 10 Hz cerebellar rTMS increased cortico-pharyngeal MEP amplitudes (mean bilateral increase 52%, P = 0.007) with effects lasting 30 min post-intervention with an optimal train length of 250 pulses (P = 0.019). These optimised parameters of cerebellar rTMS can produce sustained increases in corticobulbar excitability and may have clinical translation in future studies of neurogenic dysphagia.

fMRI and MRS measures of neuroplasticity in the pharyngeal motor cortex.

INTRODUCTION: Paired associative stimulation (PAS), is a novel non-invasive technique where two neural substrates are employed in a temporally coordinated manner in order to modulate cortico-motor excitability within the motor cortex (M1). In swallowing, combined pharyngeal electrical and transcranial-magnetic-stimulation induced beneficial neurophysiological and behavioural effects in healthy subjects and dysphagic stroke patients. Here, we aimed to investigate the whole-brain changes in neural activation during swallowing using functional magnetic resonance imaging (fMRI) following PAS application and in parallel assess associated GABA changes with magnetic resonance spectroscopy (MRS). METHODS: Healthy adults (n=11, 38±9years old) were randomised to receive real and sham PAS to the 'stronger' motor cortex pharyngeal representation, on 2 separate visits. Following PAS, event-related fMRI was performed to assess changes in brain activation in response to water and saliva swallowing and during rest. Data were analysed (SPM8) at P<.001. MRS data were acquired using MEGA-PRESS before and after the fMRI acquisitions on both visits and GABA concentrations were measured (AMARES, jMRUI). RESULTS: Following real PAS, BOLD signal changes (group analyses) increased at the site of stimulation during water and saliva swallowing, compared to sham PAS. It is also evident that PAS induced significant increases in BOLD signal to contralateral (to stimulation) hemispheric areas that are of importance to the swallowing neural network. Following real PAS, GABA:creatine ratio showed a trend to increase contralateral to PAS. CONCLUSION: Targeted PAS applied to the human pharyngeal motor cortex induces local and remote changes in both primary and non-primary areas for water and saliva tasks. There is a possibility that changes of the inhibitory neurotransmitter, GABA, may play a role in the changes in BOLD signal. These findings provide evidence for the mechanisms underlying the beneficial effects of PAS on the brain swallowing network.

Transcranial direct current stimulation reverses neurophysiological and behavioural effects of focal inhibition of human pharyngeal motor cortex on swallowing.

The human cortical swallowing system exhibits bilateral but functionally asymmetric representation in health and disease as evidenced by both focal cortical inhibition (pre-conditioning with 1 Hz repetitive transcranial magnetic stimulation; rTMS) and unilateral stroke, where disruption of the stronger (dominant) pharyngeal projection alters swallowing neurophysiology and behaviour. Moreover, excitatory neurostimulation protocols capable of reversing the disruptive effects of focal cortical inhibition have demonstrated therapeutic promise in post-stroke dysphagia when applied contralaterally. In healthy participants (n = 15, 8 males, mean age (±SEM) 35 ± 9 years), optimal parameters of transcranial direct current stimulation (tDCS) (anodal, 1.5 mA, 10 min) were applied contralaterally after 1 Hz rTMS pre-conditioning to the strongest pharyngeal projection. Swallowing neurophysiology was assessed in both hemispheres by intraluminal recordings of pharyngeal motor-evoked responses (PMEPs) to single-pulse TMS as a measure of cortical excitability. Swallowing behaviour was examined using a pressure-based reaction time protocol. Measurements were made before and for up to 60 min post intervention. Subjects were randomised to active or sham tDCS after 1 Hz rTMS on separate days and data were compared using repeated measures ANOVA. Active tDCS increased PMEPs bilaterally (F1,14 = 7.4, P = 0.017) reversing the inhibitory effects of 1 Hz rTMS in the pre-conditioned hemisphere (F1,14 = 10.1, P = 0.007). Active tDCS also enhanced swallowing behaviour, increasing the number of correctly timed challenge swallows compared to sham (F1,14 = 6.3, P = 0.025). Thus, tDCS to the contralateral pharyngeal motor cortex reverses the neurophysiological and behavioural effects of focal cortical inhibition on swallowing in healthy individuals and has therapeutic potential for dysphagia rehabilitation.

Characterization of corticobulbar pharyngeal neurophysiology in dysphagic patients with Parkinson's disease.

BACKGROUND & AIMS: Dysphagia in patients with Parkinson's disease, persisting despite dopaminergic treatment, affects intake of nutrients and medication, and reduces quality of life (QOL). We investigated the neurophysiologic mechanisms that contribute to dysphagia in these patients, on and off L-3,4-dihydroxyphenylalanine (levodopa), using transcranial magnetic stimulation. METHODS: We studied 26 patients with Parkinson's disease (age, 65 ± 9 y; 10 men). Dysphagia and QOL were first assessed with qualitative questionnaires. Twelve hours after patients were taken off levodopa, they underwent cortical transcranial magnetic stimulation mapping of the pharyngeal musculature and trigeminal (bulbar) transcranial magnetic stimulation, as well as videofluoroscopy to examine swallowing. The analyses were repeated after administration of levodopa. RESULTS: Eleven patients initially reported dysphagia and reduced QOL scores. Videofluoroscopy identified 10 patients with swallowing impairments on and off levodopa, and 6 patients with swallowing impairments only on levodopa; the remaining 10 subjects showed no swallowing impairments, on or off the drug. While patients were on levodopa, those with swallowing impairments had bilateral increases in pharyngeal cortical excitability compared with those with no swallowing impairment (P < .05). By contrast, with medication, amplitudes of brainstem reflexes were altered only in patients with swallowing impairments on levodopa; these were decreased compared with when the patients were off levodopa. CONCLUSIONS: In patients with Parkinson's disease, dopaminergic medications such as levodopa can negatively affect swallowing. The increased cortical excitability observed in dysphagic patients after they begin taking levodopa likely results from compensatory mechanisms, perhaps secondary to subcortical disease, because we observed associated inhibition of brainstem reflexes in patients with affected swallowing on medication. UK clinical trials registration no., 9882.

Dysphagia after stroke: research advances in treatment interventions.

After a stroke, most patients have dysphagia, which can lead to aspiration pneumonia, malnutrition, and adverse functional outcomes. Protective interventions aimed at reducing these complications remain the cornerstone of treatment. Dietary adjustments and oral hygiene help mitigate the risk of aspiration pneumonia, and nutritional supplementation, including tube feeding, might be needed to prevent malnutrition. Rehabilitative interventions aim to enhance swallowing function, with different behavioural strategies showing promise in small studies. Investigations have explored the use of pharmaceutical agents such as capsaicin and other Transient-Receptor-Potential-Vanilloid-1 (TRPV-1) sensory receptor agonists, which alter sensory perception in the pharynx. Neurostimulation techniques, such as transcranial direct current stimulation, repetitive transcranial magnetic stimulation, and pharyngeal electrical stimulation, might promote neuroplasticity within the sensorimotor swallowing network. Further advancements in the understanding of central and peripheral sensorimotor mechanisms in patients with dysphagia after a stroke, and during their recovery, will contribute to optimising treatment protocols.