Dysphagia in multiple system atrophy consensus statement on diagnosis, prognosis and treatment

Early-onset dysphagia predicts short survival in multiple system atrophy

BACKGROUND

The prognostic impact of dysphagia in multiple system atrophy (MSA) remains controversial. This study aimed to investigate the relationship between dysphagia severity and survival in MSA and to elucidate whether this impact differs between MSA-cerebellar ataxia (MSA-C) and MSA-parkinsonism (MSA-P).

METHODS

This retrospective study included 297 patients with MSA: 251 met criteria for clinically established MSA and 46 for clinically probable MSA. Among them, 171 had MSA-C and 126 had MSA-P. We evaluated symptomatic dysphagia within 3 years of onset and quantified dysphagia severity using the Hyodo score (0 to 12) through fibreoptic endoscopic evaluation of swallowing (FEES) and clinical features, including autonomic dysfunction and vocal cord paralysis. Patients were followed up until death or tracheostomy, and survival factors were analysed using the log-rank test and multivariate Cox proportional hazards model.

RESULTS

Ninety patients developed symptomatic dysphagia within 3 years of onset, and 75 were evaluated for dysphagia severity using FEES. Survival from onset was shorter in patients with dysphagia within 3 years compared to those without (median: 4.2 years vs. 7.3 years; p < 0.001). Symptomatic dysphagia within 3 years of onset was an independent predictor of shorter survival in the multivariate Cox analysis. While the Hyodo score was higher in MSA-P than in MSA-C patients (p = 0.048), the Hyodo score was associated with survival in both MSA-C and MSA-P patients (log-rank p < 0.001 and p = 0.046, respectively).

CONCLUSION

Symptomatic dysphagia within 3 years of onset predicts shorter survival in MSA-C and MSA-P patients.

Clinical Practices and Opinions toward Gastrostomy Use in Patients with Atypical Parkinsonian Syndromes: A National Survey in the UK

BACKGROUND

Severe dysphagia poses a significant challenge for clinicians regarding feeding tube choices, practices, and timing due to a lack of evidence-based guidance.

OBJECTIVES

To assess national clinical practices and opinions on gastrostomy use in patients with atypical parkinsonian syndromes (APS) across the UK.

METHODS

Online survey was administered to clinicians and allied health professionals regarding availability of services, current use, perceived advantages, and problems associated with gastrostomy insertion.

RESULTS

We received responses from 47 respondents across 12 UK centers, including 44 clinicians specialized in APS. Consensus was observed regarding primary indications for gastrostomy insertion and circumstances justifying avoidance of the procedure. Limitations in recommending gastrostomy due to insufficient evidence on safety and outcomes, survival and quality of life were identified. Widespread agreement on delays in gastrostomy discussions was highlighted as a challenge in optimizing patient care, together with variability in current practices and concerns over the lack of a standardized gastrostomy pathway, emphasizing the need for further research to address existing evidence gaps.

CONCLUSION

This multi-center survey highlights agreement among clinicians on key aspects of indication, challenges, and limitations such as delayed decision-making and the absence of standardized pathways regarding the timing, method, and overall approach to gastrostomy insertion in APS. This study identified next steps to facilitate a more structured approach to future research toward a consensus on best practices for gastrostomy in APS. Addressing these challenges is crucial for enhancing patient outcomes and overall care quality in APS.

Association of dysphagia severity in multiple system atrophy with the specific binding ratio on dopamine transporter SPECT

OBJECTIVE

Dysphagia in multiple system atrophy (MSA) is life-threatening and is caused by parkinsonism with cerebellar ataxia as a contributing factor. The present study investigated the relationship between dysphagia severity in MSA and the specific binding ratio (SBR) on dopamine transporter (DaT) SPECT using the Hyodo score, a qualitative scale for use with fiberoptic endoscopic evaluation of swallowing (FEES).

METHODS

Hyodo score's ability to predict aspiration during a FEES examination of 88 patients with MSA was first tested. Then the clinical characteristics, Hyodo score, and SBR of patients with either predominant parkinsonism (MSA-P; n = 11) or cerebellar ataxia (MSA-C; n = 25) who underwent FEES and DaT SPECT simultaneously were compared.

RESULTS

Logistic regression demonstrated that the Hyodo score was a significant predictive factor of aspiration (p = 0.003). The MSA-P group had a significantly higher Hyodo score (p = 0.026) and lower SBR (p = 0.011) than the MSA-C group while neither group demonstrated any significant difference in disease duration at the FEES examination. Linear regression demonstrated a significant, inverse correlation between the Hyodo score and SBR in the MSA-P (p = 0.044; r = -0.616) and MSA-C (p = 0.044; r = -0.406) groups. When the effect of SBR was removed by analysis of covariance, no significant difference in the Hyodo score remained between the groups.

CONCLUSIONS

Our results suggested an association between presynaptic changes in nigrostriatal dopaminergic neurons and dysphagia severity in MSA which largely contributes to the difference in dysphagia severity between MSA-P and MSA-C.

A multidisciplinary collaborative diagnosis and rehabilitation program for dysphagia in general hospitals

Dysphagia is a common complication of various clinical conditions, with an increased incidence as age advances. Complications such as aspiration, malnutrition, and aspiration pneumonia caused by dysphagia significantly affect the overall treatment outcomes of patients. Scholars both domestically and internationally are increasingly focusing on early rehabilitation for dysphagia. This article summarizes common conditions causing dysphagia, clinical manifestations, complications, screening assessment, diagnosis, rehabilitation, and nutritional support related to dysphagia. It emphasizes the arrival at a multidisciplinary collaborative diagnosis and formulation of a rehabilitation management plan for dysphagia in general hospitals in order to provide strategic suggestions for establishing a multidisciplinary collaborative model for swallowing disorder management in general hospitals.

Swallowing Characteristics in Patients with Multiple System Atrophy Analyzed Using FEES Examination

Patients with multiple system atrophy (MSA) frequently experience dysphagia but only few studies analyzed its characteristics. The aim of this study was to describe the swallowing characteristics in these patients using fiberoptic endoscopic evaluation of swallowing (FEES). In addition, the swallowing abilities in patients with predominantly cerebellar MSA (MSA-C) and predominantly parkinsonian MSA (MSA-P) were compared. Twenty-five patients with MSA (16 MSA-P and 9 MSA-C) were enrolled. Clinical data including age, sex, functional oral intake scale (FOIS) score, body mass index (BMI) and the results of the global disability-unified MSA rating scale (GD-UMSARS) were collected. Three different textures of food (liquid, semisolid, solid) were provided during FEES examination. The characteristics of dysphagia (safety, efficiency, phenotype) and laryngeal movement alterations were analyzed. Delayed pharyngeal phase (92%) and posterior oral incontinence (52%) were the phenotypes more frequently seen. Penetration was more frequent with Liquid (68%), while aspiration occurred only with Liquid (20%). Residues of ingested food were demonstrated both in the pyriform sinus and in the vallecula with all the consistencies. Vocal fold motion impairment was the laryngeal movement alteration most frequently encountered (56%). No significant differences between patients with MSA-P and MSA-C in the dysphagia characteristics and laryngeal movement alterations were found. Patients with MSA frequently experience swallowing impairment and altered laryngeal mobility. Dysphagia characteristics and laryngeal movements alterations seems to be similar in MSA-C and MSA-P.

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.

Systematic approach to contextualize findings of flexible endoscopic evaluation of swallowing in neurogenic dysphagia- towards an integrated FEES report

Flexible endoscopic evaluation of swallowing (FEES) is one of the most important methods for instrumental swallowing evaluation. The most challenging part of the examination consists in the interpretation of the various observations encountered during endoscopy and in the deduction of clinical consequences. This review proposes the framework for an integrated FEES-report that systematically moves from salient findings of FEES to more advanced domains such as dysphagia severity, phenotypes of swallowing impairment and pathomechanisms. Validated scales and scores are used to enhance the diagnostic yield. In the concluding part of the report, FEES-findings are put into the perspective of the clinical context. The potential etiology of dysphagia and conceivable differential diagnoses are considered, further diagnostic steps are proposed, treatment options are evaluated, and a timeframe for re-assessment is suggested. This framework is designed to be adaptable and open to continuous evolution. Additional items, such as novel FEES protocols, pathophysiological observations, advancements in disease-related knowledge, and new treatment options, can be easily incorporated. Moreover, there is potential for customizing this approach to report on FEES in structural dysphagia.

Inhibiting cholinergic signalling in the cerebellar interpositus nucleus impairs motor behaviour

The role of neuromodulators in the cerebellum is not well understood. In particular, the behavioural significance of the cholinergic system in the cerebellum is unknown. To investigate the importance of cerebellar cholinergic signalling in behaviour, we infused acetylcholine receptor antagonists, scopolamine and mecamylamine, bilaterally into the rat cerebellum (centred on interpositus nucleus) and observed the motor effects through a battery of behavioural tests. These tests included unrewarded behaviour during open field exploration and a horizontal ladder walking task and reward-based beam walking and pellet reaching tasks. Infusion of a mix of the antagonists did not impair motor learning in the horizontal ladder walking or the reaching task but reduced spontaneous movement during open field exploration, impaired coordination during beam walking and ladder walking, led to fewer reaches in the pellet reaching task, slowed goal-directed reaching behaviour and reduced reward pellet consumption in a free access to food task. Infusion of the muscarinic antagonist scopolamine on its own resulted in deficits in motor performance and a reduction in the number of reward pellets consumed in the free access to food task. By contrast, infusion of the nicotinic antagonist mecamylamine on its own had no significant effect on any task, except beam walking traversal time, which was reduced. Together, these data suggest that acetylcholine in the cerebellar interpositus nucleus is important for the execution and coordination of voluntary movements mainly via muscarinic receptor signalling, especially in relation to reward-related behaviour.

Data-Driven Subtypes of Multiple System Atrophy and Their Implications for Prognosis

Background

While multiple system atrophy (MSA) presents with high heterogeneous motor and nonmotor symptoms, the associations between clinical phenotypes and prognosis are unclear.

Objective

We aimed to evaluate clinical phenotypes of MSA using data-driven approach and measure the impact of phenotypes on survival and bedbound status.

Methods

193 MSA patients were recruited from Xuanwu Hospital Capital Medical University, whose history, motor and non-motor symptoms were examined using cluster analysis. Ninety-five participants were followed-up via telephone after a mean of 31.87 months. We employed Kaplan- Meier analysis to examine survival and performed Cox and logistic regression analyses to identify factors associated with survival and bedbound status.

Results

We identified four clinical profiles of MSA: cerebellar symptom-dominant, sleep and mood disorder-dominant, rigid akinetic-dominant, and malignant diffuse. The overall median survival was 7.75 years (95% CI 7.19-8.31). After adjusting for years from symptom onset to diagnosis, age and sex, patients in the malignant diffuse and rigid akinetic-dominant clusters had greater risk of death than sleep and mood disorder-dominant cluster. Furthermore, patients in the malignant diffuse and rigid akinetic-dominant clusters had higher risk of being bedbound than cerebellar symptom-dominant cluster.

Conclusions

The malignant diffuse and sleep and mood disorder-dominant were identified besides the two classical subtypes, parkinsonism, and cerebellar symptom-variant. Patients with rigid-akinetic motor profiles have a worse prognosis than cerebellar symptom-dominant profiles in general. Diffuse symptoms, especially postural instability, and cognitive alterations at diagnosis, indicate rapid functional loss and disease progression. The different profiles and prognoses might indicate varied underlying pathological mechanisms.

Management and Treatment for Dysphagia in Neurodegenerative Disorders

Patients with neurodegenerative disorders (NDDs) often experience functional dysphagia, which may involve dysfunction in a specific phase of swallowing or in the entire process. This review outlines the approach to dysphagia in the setting of NDDs. Distinguishing the etiology of dysphagia can be difficult, and it is important to always look out for signs pointing to NDD as the cause. Thorough diagnostic work-up is essential, and it includes a comprehensive history and physical examination, alongside swallowing function tests, such as fiberoptic endoscopic evaluation of swallowing, videofluoroscopic swallowing study, and high-resolution manometry. Management requires a multidisciplinary approach with a treatment plan tailored to each patient. This involves dietary guidance, swallowing rehabilitation, and surgery in cases in which improvement with rehabilitation is inadequate. Surgery may involve altering certain pharyngolaryngeal structures to facilitate swallowing and reduce the risk of aspiration (swallowing improvement surgery) or separating the airway and digestive tract while sacrificing laryngeal function, with the main goal of preventing aspiration (aspiration prevention surgery). Proper management stems from recognizing the impact of these disorders on swallowing and consistently finding ways to improve the quality of life of patients.

Deterioration of Cough, Respiratory, and Vocal Cord Functions in Patients with Multiple System Atrophy

The purpose of this study was to clarify changes in cough function in patients with multiple system atrophy (MSA). Seventeen probable patients with MSA were studied. Peak cough flow (PCF), respiratory function (percentage of vital capacity, percentage of forced vital capacity, and percentage of predicted forced expiratory volume in one second), respiratory muscle strength (percentage of maximal inspiratory mouth pressure and percentage of maximal expiratory mouth pressure), and maximum phonation time (MPT) were assessed. Walking ability, disease duration, possibility of air stacking, Unified MSA Rating Scale (UMSARS), and Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS) Part III were also assessed. Data were separately analyzed for ambulatory and non-ambulatory groups categorized by Functional Ambulation Categories. PCF, respiratory function, respiratory muscle strength, and MPT were significantly lower in the non-ambulatory group than in the ambulatory group. On the other hand, no correlation between PCF and disease duration was observed. A significant number of patients in the non-ambulatory group were unable to hold their breath. The UMSARS and MDS-UPDRS Part III in the non-ambulatory group were significantly higher than in the ambulatory group. It was concluded that ambulatory dysfunction is associated with the decline of cough function and respiratory-related function in patients with MSA.

Development and Validation of a Prognostic Model to Predict Overall Survival in Multiple System Atrophy

Background

Multiple system atrophy (MSA) is a devastating disease characterized by a variable combination of motor and autonomic symptoms. Previous studies identified numerous clinical factors to be associated with shorter survival.

Objective

To enable personalized patient counseling, we aimed at developing a risk model of survival based on baseline clinical symptoms.

Methods

MSA patients referred to the Movement Disorders Unit in Innsbruck, Austria, between 1999 and 2016 were retrospectively analyzed. Kaplan-Meier curves and multivariate Cox regression analysis with least absolute shrinkage and selection operator penalty for variable selection were performed to identify prognostic factors. A nomogram was developed to estimate the 7 years overall survival probability. The performance of the predictive model was validated and calibrated internally using bootstrap resampling and externally using data from the prospective European MSA Study Group Natural History Study.

Results

A total of 210 MSA patients were included in this analysis, of which 124 patients died. The median survival was 7 years. The following clinical variables were found to significantly affect overall survival and were included in the nomogram: age at symptom onset, falls within 3 years of onset, early autonomic failure including orthostatic hypotension and urogenital failure, and lacking levodopa response. The time-dependent area under curve for internal and external validation was >0.7 within the first 7 years of the disease course. The model was well calibrated showing good overlap between predicted and actual survival probability at 7 years.

Conclusion

The nomogram is a simple tool to predict survival on an individual basis and may help to improve counseling and treatment of MSA patients.

Significance of clinical symptoms and red flags in early differential diagnosis of Parkinson's disease and atypical Parkinsonian syndromes

The clinical presentation of Parkinson's disease and atypical Parkinsonian syndromes is often heterogeneous. Additional diagnostic procedures including brain imaging and biomarker analyses can help to appreciate the various syndromes, but a precise clinical evaluation and differentiation is always necessary. To better assess the relevance of distinct clinical symptoms that arose within 1 year of disease manifestation and evaluate their indicative potential for an atypical Parkinsonian syndrome, we conducted a modified Delphi panel with seven movement disorder specialists. Five different topics with several clinical symptom items were discussed and consensus criteria were tested. This resulted in distinct symptom patterns for each atypical Parkinsonian syndrome showing the multitude of clinical involvement in each neurodegenerative disease. Strongly discriminating clinical signs were few and levels of indication were variable. A prospective validation of the assessments made is needed. This demonstrates that both clinical evaluation and elaborate additional diagnostic procedures are needed to achieve a high diagnostic standard.

Multiple system atrophy

This is a practical guide to diagnosing and managing multiple system atrophy (MSA). We explain the newly published Movement Disorders Society Consensus Diagnostic Criteria, which include new 'Clinically Established MSA' and 'Possible Prodromal MSA' categories, hopefully reducing time to diagnosis. We then highlight the key clinical features of MSA to aid diagnosis. We include a list of MSA mimics with suggested methods of differentiation from MSA. Lastly, we discuss practical symptom management in people living with MSA, including balancing side effects, with the ultimate aim of improving quality of life.

Synucleinopathies

The α-synucleinopathies include pure autonomic failure, multiple system atrophy, dementia with Lewy bodies, and Parkinson disease. The past two decades have witnessed significant advances in the diagnostic strategies and symptomatic treatment of motor and nonmotor symptoms of the synucleinopathies. This chapter provides an in-depth review of the pathophysiology, pathology, genetic, epidemiology, and clinical and laboratory autonomic features that distinguish the different synucleinopathies with an emphasis on autonomic failure as a common feature. The treatment of the different synucleinopathies is discussed along with the proposal for multidisciplinary, individualized care models that optimally address the various symptoms. There is an urgent need for clinical scientific studies addressing patients at risk of developing synucleinopathies and the investigation of disease mechanisms, biomarkers, potential disease-modifying therapies, and further advancement of symptomatic treatments for motor and nonmotor symptoms.

Multiple system atrophy

Multiple system atrophy (MSA) is a rare neurodegenerative disease that is characterized by neuronal loss and gliosis in multiple areas of the central nervous system including striatonigral, olivopontocerebellar and central autonomic structures. Oligodendroglial cytoplasmic inclusions containing misfolded and aggregated α-synuclein are the histopathological hallmark of MSA. A firm clinical diagnosis requires the presence of autonomic dysfunction in combination with parkinsonism that responds poorly to levodopa and/or cerebellar ataxia. Clinical diagnostic accuracy is suboptimal in early disease because of phenotypic overlaps with Parkinson disease or other types of degenerative parkinsonism as well as with other cerebellar disorders. The symptomatic management of MSA requires a complex multimodal approach to compensate for autonomic failure, alleviate parkinsonism and cerebellar ataxia and associated disabilities. None of the available treatments significantly slows the aggressive course of MSA. Despite several failed trials in the past, a robust pipeline of putative disease-modifying agents, along with progress towards early diagnosis and the development of sensitive diagnostic and progression biomarkers for MSA, offer new hope for patients.

Relationship Between Pneumonia and Dysphagia in Patients With Multiple System Atrophy

Introduction

Dysphagia is one of the most clinically significant disabilities in patients with multiple system atrophy (MSA), because it can cause aspiration pneumonia, which is potentially fatal. In this study, the Neuromuscular disease Swallowing Status Scale (NdSSS), which was developed to evaluate dysphagia in patients with neuromuscular diseases, was used to evaluate patients with MSA. In addition, correlation between a history of pneumonia and swallowing function was evaluated.

Methods

Study 1: Reliability, concurrent validity, and responsiveness of the NdSSS in patients with MSA. In 81 patients for whom evaluation items could be collected, the NdSSS was tested for its interrater and intrarater reliability using weighted kappa statistics. Concurrent validity was assessed by correlating the NdSSS with existing scales (Functional Oral Intake Scale (FOIS), Functional Intake LEVEL Scale (FILS), and the unified MSA rating scale (UMSARS)) using Spearman's rank correlation coefficients. Sixty-three patients were evaluated by videofluorographic (VF) swallowing examination. To evaluate concurrent validity, Spearman's rank correlation coefficients were calculated between the NdSSS and VF swallowing assessments. Additionally, scale responsiveness was determined using the standardized response mean (SRM) in 23 patients who could be followed up to assess their long-term course. Study 2: Cross-sectional survey of swallowing function and history of pneumonia. Data regarding history of pneumonia, UMSARS, NdSSS, age, sex, MSA subtype, and disease duration were retrospectively obtained from the medical records of 113 patients with MSA. Differences in these parameters and NdSSS stage between those with and without a history of pneumonia were examined using the Mann-Whitney test or chi-squared test. Furthermore, clinical factors related to a history of pneumonia were examined by binomial logistic regression analysis.

Results

The NdSSS showed satisfactory reliability, concurrent validity, and responsiveness. A history of pneumonia was related to the severity of MSA, age, MSA subtype, and NdSSS stage. Binomial logistic regression analysis showed that NdSSS stage (odds ratio (OR), 0.490; 95% confidence interval (CI), 0.301–0.797, p = 0.001) and MSA subtype (OR, 4.031; 95% CI, 1.225–13.269, p = 0.021) were significantly associated with a history of pneumonia.

Conclusions

In patients with MSA, the NdSSS has sufficient reliability, concurrent validity, and responsiveness for assessing dysphagia. Patients with a history of pneumonia have more severe dysphagia. We found that the pneumonia risk was related to NdSSS stage and MSA-p (predominantly parkinsonism). Meticulous care to prevent aspiration is needed from early stages of the disease.

Improving the Accuracy of Diagnosis for Multiple-System Atrophy Using Deep Learning-Based Method

Multiple-system atrophy (MSA) is primarily an autonomic disorder with parkinsonism or cerebellar ataxia. Clinical diagnosis of MSA at an early stage is challenging because the symptoms change over the course of the disease. Recently, various artificial intelligence-based programs have been developed to improve the diagnostic accuracy of neurodegenerative diseases, but most are limited to the evaluation of diagnostic imaging. In this study, we examined the validity of diagnosis of MSA using a pointwise linear model (deep learning-based method). The goal of the study was to identify features associated with disease differentiation that were found to be important in deep learning. A total of 3377 registered MSA cases from FY2004 to FY2008 were used to train the model. The diagnostic probabilities of SND (striatonigral degeneration), SDS (Shy-Drager syndrome), and OPCA (olivopontocerebellar atrophy) were estimated to be 0.852 ± 0.107, 0.650 ± 0.235, and 0.858 ± 0.270, respectively. In the pointwise linear model used to identify and visualize features involved in individual subtypes, autonomic dysfunction was found to be a more prominent component of SDS compared to SND and OPCA. Similarly, respiratory failure was identified as a characteristic of SDS, dysphagia was identified as a characteristic of SND, and brain-stem atrophy was identified as a characteristic of OPCA.

Pharyngolaryngeal semiology and prognostic factors in multiple system atrophy

Introduction

Multiple system atrophy (MSA) is a rare degenerative neurological disorder in adults. It induces parkinsonian and/or cerebellar syndrome associated with dysautonomia. Pharyngolaryngeal symptoms are common. Our aim is to describe the Pharyngolaryngeal semiology on one hand, and to ascertain whether the presence of these symptoms represents a prognostic factor for MSA on the other.

Methods

Thus, we carried out a retrospective, single-centre study, on a cohort receiving care at the centre of reference for MSA. The patients were referred for otorhinolaryngology assessment. The data was collected over the year 2020 with the help of computer software from the university hospital centre (UHC). Firstly, we described the Pharyngolaryngeal semiology specific to MSA by questioning patients, and by the results of nasofibroscopic examinations and swallowing tests. We then used multivariate analysis of variance to describe the prognostic factors of MSA progression (in UMSARS I and II points per month of progression) and survival (number of years between the first symptoms and death).

Results

This study included a hundred and one patients and made it possible to define a Pharyngolaryngeal semiology profile of MSA, which is: a reduction in laryngeal mobility (primarily vocal cord abduction defects), abnormal movements (particularly at rest or when initiating a movement) and a defect in the protection mechanisms of the upper airways. The swallowing difficulties are moderate and the main mechanisms are delayed pharyngeal swallow and/or an oro-pharyngeal transport defect. In the multivariate analyses, the contributing factors are laryngeal anomalies, modification of solid food to fluid food and nutritional complication.

Conclusion

ENT specialists should pay close attention to problems in the Pharyngolaryngeal dynamic and then consider a neurological cause. They can also itemize the clinical factors that could have a negative effect on the prognosis of the patient with MSA. Indeed, early detection makes it possible to provide care for respiratory and nutritional complications.

Neuropathology and molecular diagnosis of Synucleinopathies

Synucleinopathies are clinically and pathologically heterogeneous disorders characterized by pathologic aggregates of α-synuclein in neurons and glia, in the form of Lewy bodies, Lewy neurites, neuronal cytoplasmic inclusions, and glial cytoplasmic inclusions. Synucleinopathies can be divided into two major disease entities: Lewy body disease and multiple system atrophy (MSA). Common clinical presentations of Lewy body disease are Parkinson's disease (PD), PD with dementia, and dementia with Lewy bodies (DLB), while MSA has two major clinical subtypes, MSA with predominant cerebellar ataxia and MSA with predominant parkinsonism. There are currently no disease-modifying therapies for the synucleinopathies, but information obtained from molecular genetics and models that explore mechanisms of α-synuclein conversion to pathologic oligomers and insoluble fibrils offer hope for eventual therapies. It remains unclear how α-synuclein can be associated with distinct cellular pathologies (e.g., Lewy bodies and glial cytoplasmic inclusions) and what factors determine neuroanatomical and cell type vulnerability. Accumulating evidence from in vitro and in vivo experiments suggests that α-synuclein species derived from Lewy body disease and MSA are distinct "strains" having different seeding properties. Recent advancements in in vitro seeding assays, such as real-time quaking-induced conversion (RT-QuIC) and protein misfolding cyclic amplification (PMCA), not only demonstrate distinct seeding activity in the synucleinopathies, but also offer exciting opportunities for molecular diagnosis using readily accessible peripheral tissue samples. Cryogenic electron microscopy (cryo-EM) structural studies of α-synuclein derived from recombinant or brain-derived filaments provide new insight into mechanisms of seeding in synucleinopathies. In this review, we describe clinical, genetic and neuropathologic features of synucleinopathies, including a discussion of the evolution of classification and staging of Lewy body disease. We also provide a brief discussion on proposed mechanisms of Lewy body formation, as well as evidence supporting the existence of distinct α-synuclein strains in Lewy body disease and MSA.

Early recognition and diagnosis of multiple system atrophy: best practice and emerging concepts

Introduction: Multiple system atrophy (MSA) is a progressive degenerative disorder of the central and autonomic nervous systems characterized by parkinsonism, cerebellar ataxia, dysautonomia, and pyramidal signs. The confirmatory diagnosis is pathological, but clinical-diagnostic criteria have been developed to help clinicians. To date, the early diagnosis of MSA is challenging due to the lack of reliable diagnostic biomarkers.Areas covered: The authors reappraised the main clinical, neurophysiological, imaging, genetic, and laboratory evidence to help in the early diagnosis of MSA in the clinical and in the research settings. They also addressed the practical clinical issues in the differential diagnosis between MSA and other parkinsonian and cerebellar syndromes. Finally, the authors summarized the unmet needs in the early diagnosis of MSA and proposed the next steps for future research efforts in this field.Expert opinion: In the last decade, many advances have been achieved to help the correct MSA diagnosis since early stages. In the next future, the early diagnosis and correct classification of MSA, together with a better knowledge of the causative mechanisms of the disease, will hopefully allow the identification of suitable candidates to enroll in clinical trials and select the most appropriate disease-modifying strategies to slow down disease progression.

A Systematic Review of Oropharyngeal Dysphagia Models in Rodents

Oropharyngeal dysphagia is a condition characterized by swallowing difficulty in the mouth and pharynx, which can be due to various factors. Animal models of oropharyngeal dysphagia are essential to confirm the cause-specific symptoms, pathological findings, and the effect of treatment. Recently, various animal models of dysphagia have been reported. The purpose of this review is to organize the rodent models of oropharyngeal dysphagia reported to date. The articles were obtained from Medline, Embase, and the Cochrane library, and selected following the PRISMA guideline. The animal models in which oropharyngeal dysphagia was induced in rats or mice were selected and classified based on the diseases causing oropharyngeal dysphagia. The animal used, method of inducing dysphagia, and screening methods and results were collected from the selected 37 articles. Various rodent models of oropharyngeal dysphagia provide distinctive information on atypical swallowing. Applying and analyzing the treatment in rodent models of dysphagia induced from various causes is an essential process to develop symptom-specific treatments. Therefore, the results of this study provide fundamental and important data for selecting appropriate animal models to study dysphagia.