Videofluoroscopic assessment of swallowing function in patients with myasthenia gravis

Dynamic suprahyoid muscle ultrasound in assessing oropharyngeal dysphagia in neurological disorders

BACKGROUND

Appropriate evaluation and management of dysphagia are essential in neurological disorders. However, there is currently a lack of a simple yet reliable method for dysphagia evaluation.

AIM

This study aimed to investigate the usefulness of new dynamic M-mode ultrasonography (US) parameters of suprahyoid muscle (SHM) to evaluate dysphagia.

DESIGN

Prospective observational, cross-sectional study.

SETTING

Inpatient setting at neurology department of tertiary medical center.

POPULATION

A total of 89 patients with dysphagia and 175 healthy volunteers were enrolled in the study. Patients were subdivided into mild and severe dysphagia groups depending on the need for dietary changes and disease classification, which included amyotrophic lateral sclerosis, peripheral neuromuscular diseases, and stroke.

METHODS

Dynamic M-mode US was performed during swallowing to obtain the SHM thickness (the baseline thickness of the SHM), SHM displacement (peak-to-peak amplitude of SHM movement), SHM difference (SHM displacement - SHM thickness), SHM ratio (SHM displacement/SHM thickness), peak-to-peak time, and total duration. A videofluoroscopic swallowing study (VFSS) was performed.

RESULTS

Significant differences were found in SHM displacement and SHM difference according to dysphagia severity (P<0.001). The SHM ratio, total duration (P<0.001), and peak-to-peak time (P=0.001) differed significantly according to the patients' underlying diseases. The pharyngeal delay time and penetration-aspiration scale from the VFSS demonstrated significant negative correlations with SHM displacement and difference (P<0.001). By combining SHM difference and total duration, patients with dysphagia could be distinguished from healthy controls, with the highest negative predictive value of 95.6%.

CONCLUSIONS

Dynamic M-mode US of the SHM provided added value in evaluating the severity of dysphagia and differentiating swallowing mechanics of dysphagia related to underlying neurological disorders.

CLINICAL REHABILITATION IMPACT

Dynamic M-mode US of the SHM can serve as a supportive tool for rapid screening and repetitive follow-up of patients with dysphagia, which would contribute to dysphagia rehabilitation in patients with various neurological disorders.

Palatal prolapse during nasal expiration in patients with myasthenia gravis

INTRODUCTION/AIMS

We have encountered patients with myasthenia gravis (MG) who exhibited palatal prolapse (PP) during nasal expiration in the supine position while awake. This may be an overlooked cause of dyspnea in MG patients. This study aimed to examine and describe the characteristics of MG patients with PP.

METHODS

We reviewed the medical records of 183 consecutive patients who were diagnosed with MG in our hospital from 2012 to 2021. Thirty-two patients underwent laryngoscopy because of bulbar symptoms. Eight of these patients (25%) exhibited PP on laryngoscopy. Clinical features of these eight patients were retrospectively characterized.

RESULTS

Median age of the eight patients with PP was 70 years. Six were men. Median body mass index was 21.6 kg/m2 . All patients exhibited PP in the supine position but not the sitting position. Although no patient had abnormal findings on spirometry nor chest computed tomography, six reported dyspnea or difficulty with nasal expiration only in the supine position. PP improved in all four patients who underwent edrophonium testing. All eight patients eventually improved after immunotherapy.

DISCUSSION

PP during nasal expiration may be a cause of dyspnea in MG patients, along with respiratory muscle impairment, lung disease, and vocal cord paralysis. Laryngoscopy in the supine position is required to confirm.

Detecting myositis as a cause of unexplained dysphagia: Proposal for a diagnostic algorithm

BACKGROUND AND PURPOSE

Idiopathic inflammatory myopathy (IIM) can present with dysphagia as a leading or only symptom. In such cases, diagnostic evaluation may be difficult, especially if serological and electromyographical findings are unsuspicious. In this observational study we propose and evaluate a diagnostic algorithm to identify IIM as a cause of unexplained dysphagia.

METHODS

Over a period of 4 years, patients with unexplained dysphagia were offered diagnostic evaluation according to a specific algorithm: The pattern of dysphagia was characterized by instrumental assessment (swallowing endoscopy, videofluoroscopy, high-resolution manometry). Patients with an IIM-compatible dysphagia pattern were subjected to further IIM-focused diagnostic procedures, including whole-body muscle magnetic resonance imaging, electromyography, creatine kinase blood level, IIM antibody panel and, as a final diagnostic step, muscle biopsy. Muscle biopsies were taken from affected muscles. In cases where no other muscles showed abnormalities, the cricopharyngeal muscle was targeted.

RESULTS

Seventy-two patients presented with IIM-compatible dysphagia as a leading or only symptom. As a result of the specific diagnostic approach, 19 of these patients were diagnosed with IIM according to the European League Against Rheumatism (EULAR) criteria. Eighteen patients received immunomodulatory therapy as a result of the diagnosis. Of 10 patients with follow-up swallowing examination, dysphagia improved in three patients after therapy, while it remained at least stable in six patients.

CONCLUSIONS

Idiopathic inflammatory myopathy constitutes a potentially treatable etiology in patients with unexplained dysphagia. The diagnostic algorithm presented in this study helps to identify patients with an IIM-compatible dysphagia pattern and to assign those patients for further IIM-focused diagnostic and therapeutic procedures.

Neuromuscular Specializations of the Human Hypopharyngeal Muscles

The hypopharyngeal muscles in humans play a vital role in swallowing, speech, and respiration. Increasing evidence indicates that these muscles are specialized to perform life-sustaining upper aerodigestive functions. This review aims to provide current knowledge regarding the key structural, physiological, and biochemical features of the hypopharyngeal muscles, including innervation, contractile properties, histochemistry, biochemical properties, myosin heavy chain (MyHC) expression and regulation, and age-related alterations. These would clarify the unique neuromuscular specializations of the human hypopharyngeal muscles for a better understanding of the functions and pathological conditions of the pharynx and for the development of novel therapies to treat related upper airway disorders.

Impact of Fiberoptic Endoscopic Evaluation of Swallowing Outcomes and Dysphagia Management in Neurodegenerative Diseases

OBJECTIVES/HYPOTHESIS

To determine the incidence of abnormal fiberoptic endoscopic evaluation of swallowing (FEES) findings in patients with progressive neurologic disorders and identify the most commonly implemented dysphagia management strategies.

STUDY DESIGN

Retrospective Review.

METHODS

A retrospective review was performed of patients with neurodegenerative disease who underwent FEES at a tertiary-care center between 2008 and 2019. Patient demographics, diagnosis, and Eating Assessment Tool-10 (EAT-10) scores were recorded. Rates of penetration, aspiration, and functional change in management (FCIM) to include dietary modifications, home exercises, swallow therapy, surgical intervention (injection augmentation or esophageal dilation), or alternative means of nutrition (i.e., percutaneous enteral gastrostomy [PEG] tube) were calculated.

RESULTS

Two hundred nine FEES assessments were performed in 178 patients with a mean age of 64.8 years (standard deviation = ±14). The most common diagnoses were amyotrophic lateral sclerosis (32%) followed by Parkinson's disease or Parkinsonism (26%). FEES demonstrated penetration in 72.5% of patients and aspiration in 14.6%. Mean EAT-10 scores differed between patients with aspiration versus penetration versus normal FEES (24.7 vs. 14.9 vs. 13.9, respectively, P < .001). An FCIM was recommended in 88% of patients and most commonly included self-directed modifications (43%). Overall, 4.5% of patients underwent surgical intervention. A PEG tube was recommended for either supplemental or sole form of nutrition in 19% of the entire cohort.

CONCLUSIONS

Most patients with neurodegenerative diseases presenting with dysphagia demonstrated abnormal FEES findings necessitating an FCIM, suggesting early dysphagia evaluation may be warranted in this cohort. These findings correlate with worsened EAT-10 scores in patients with aspiration or penetration on FEES.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:726-730, 2021.

Screening and evaluation tools of dysphagia in adults with neuromuscular diseases: a systematic review

Background:

The purpose of this systematic review was to summarize the different dysphagia screening and evaluation tools, and to identify their measurement properties in adults with neuromuscular diseases (NMDs).

Methods:

A systematic review was performed based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The search strategy was conducted across three databases (PubMed, CINAHL and ScienceDirect). Measurement properties of each tools and the Quality Index, developed by Downs and Black, were considered for the different investigated studies.

Results:

The search strategy produced 2221 articles. After removal of duplicates and full-text analysis, 19 studies were included. Most of the publications focused on amyotrophic lateral sclerosis (ALS; n = 10) and Duchenne muscular dystrophy (DMD; n = 4). A total of 12 tools, listed as instrumental and noninstrumental examinations, were retrieved. A total of five of them used videofluoroscopic swallow study (VFSS). Measurement properties of the tools are not completely described in detail in many studies. The neuromuscular disease swallowing status scale, a noninstrumental tool, is the only one that assessed all measurement properties in ALS patients. The median score reported for the Quality Index was 16.

Conclusions:

This systematic review identified 12 different tools for the screening and evaluation of dysphagia in adults with NMD. Majority of the studies presented VFSS as a valid and reliable examination to assess dysphagia in ALS and DMD. Other tools were mainly evaluated in ALS patients, but further studies are needed to complete their measurement properties. In other NMDs, no firm conclusion can be made because of insufficient data and heterogeneity of NMDs.

Dysphagia in myasthenia gravis: the tip of the Iceberg

We evaluated swallowing function in patients with myasthenia gravis (MG) with or without dysphagia symptoms using different evaluation parameters and compared the results with those of healthy subjects. A total of 36 patients with MG and 25 healthy volunteers were included in the study. The subjects were classified into three groups; patients without dysphagia (group 1), patients with dysphagia (group 2), and healthy participants (group 3). The presence and severity of dysphagia, the oropharyngeal, pharyngeal, pharyngoesophageal, and esophageal phases were assessed using a screening test, manometric test, electrophysiologic studies [electroneuromyography (EMG)], fiberoptic endoscopic evaluation of swallowing (FEES), and barium swallow pharyngeal esophagography (BSPE), respectively. There was a significant difference between group 1 and group 3 in terms of BSPE (p = 0.001) and manometry tests (p = 0.001). A significant difference was found in all methods between group 2 and group 3 (p = 0.001, for all). In the comparison of the patient groups, although the number of patients with dysphagia in group 2 was significantly higher in the clinical tests (p = 0.007), FEES (p = 0.001), and EMG (p = 0.043) than in group 1, no difference was detected for BSPE (p = 0.119) and manometry (p = 0.644). Swallowing functions in patients with MG may be affected even without symptoms. This condition should be considered in their follow-up.

Screening and evaluation tools of dysphagia in children with neuromuscular diseases: a systematic review

AIM

Dysphagia is frequent in paediatric patients with neuromuscular diseases (pNMD). Its detection is important for initiating early diagnosis and treatment as well as for minimizing related complications. The aim of this study was to review the literature on dysphagia screening and evaluation tools in pNMD.

METHOD

A systematic review was performed on the basis of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Three databases (PubMed, CINAHL, and ScienceDirect) were searched. Measurement properties of tools and the quality index developed by Downs and Black were considered.

RESULTS

Our search yielded four studies and four different tools for paediatric patients with Duchenne muscular dystrophy (DMD). The Sydney Swallow Questionnaire, surface electromyography, Neuromuscular Disease Swallowing Status Scale, and videofluoroscopic swallow study showed interesting properties for DMD. No data were available for other NMD and children under 9 years. The mean total score for the quality index was 17.5.

INTERPRETATION

We did not identify any superior validated tools, either for screening or for evaluation of dysphagia, and no widely accepted protocol. Further studies are needed to identify the simplest assessment with the best psychometric properties for pNMD. We recommend establishing a specific tool for pNMD.

Measurement of swallowing using flexible polymer sensor

We proposed a new method to measure swallowing in this study. A flexible polymer sensor was used to measure human swallowing. Electromyogram (EMG) of suprahyoid muscles were measured as a reference of swallowing. We also developed a measurement system for the flexible polymer sensor, which consists of two measurement circuits; the 1(st) one measures the voltage of flexible polymer sensor, and the 2(nd) one EMG of suprahyoid muscles. We conducted measurement experiments focused on human swallowing to confirm the ability of this sensor. At the experiment one subject was asked to sit in three different postures and to drink a cup of water. Results show that human swallowing can be detected by this flexible polymer sensor.

Videofluorographic detection of anti-muscle-specific kinase-positive myasthenia gravis

A 47-year-old woman with dysphagia and ptosis gradually developed dysarthria and muscular weakness. Magnetic resonance imaging, testing for anti-acetylcholine receptor antibodies, edrophonium chloride (EC) test, and electrophysiologic test revealed no abnormalities. A psychogenic reaction was suspected. Four months after disease onset, the patient presented to our hospital. In videofluoroscopic examination of swallowing (VF), there was no aspiration for swallowing of either liquid or soft food. It revealed, however, poor pharyngeal constriction, no epiglottis inversion, repeated swallowing movements, and large amounts of pharyngeal residue. Videofluoroscopic examination of swallowing after an intravenous injection of 10 mg EC showed improvements in all above observations; particularly, it was clear when swallowing soft food. Furthermore, the anti-muscle-specific kinase (MuSK) antibody titer was elevated, and anti-MuSK antibody-positive myasthenia gravis (MuSK-MG) was diagnosed. Thus VF during EC test may be helpful in diagnosing MuSK-MG in patients with dysphagia.

Treatment of velopharyngeal inadequacy in a patient with submucous cleft palate and myasthenia gravis

OBJECTIVE

To describe the clinical course and management of a patient with submucous cleft palate who developed myasthenia gravis (MG) as an adult and suffered recurrent hypernasality. Few reports have described MG patients undergoing pharyngeal flap surgery for velopharyngeal incompetence, and these have described only slight speech improvement in such patients.

DESIGN

Case report.

PATIENT

The patient underwent primary pushback palatoplasty and superiorly based pharyngeal flap surgery for submucous cleft and short palate at age 7. Hypernasality showed major improvement after initial surgery. At age 19, the patient developed MG that triggered the recurrence of velopharyngeal incompetence.

INTERVENTION

After MG was treated, revision pushback palatoplasty was performed for velopharyngeal incompetence when the patient was 24 years old. Preoperatively and postoperatively, the patient was evaluated by the same speech-language-hearing therapists, each with at least 5 years of clinical experience in cleft palate speech.

RESULTS

After the second pushback palatoplasty, hypernasality and audible nasal air emission during speech decreased to mild.

CONCLUSION

Primary pushback palatoplasty and pharyngeal flap surgery were performed for the submucous cleft palate. Revision pushback palatoplasty improved velopharyngeal inadequacy induced by MG. Decreased perceived nasality positively influenced the patient's quality of life. Combined pushback palatoplasty and pharyngeal flap surgery is thus an option in surgical treatment for velopharyngeal inadequacy to close the cleft and the velopharyngeal orifice in cases of cleft palate and MG.

MuSK-antibody positive myasthenia gravis: questions from the clinic

Clinical vignettes are presented of five patients with MuSK-antibody positive myasthenia gravis, each of which demonstrates a diagnostic or therapeutic issue that is unique to or characteristic of this condition. Consideration of these issues leads to questions, many of which are unanswered at this time, about the immunopathology and management of this subset of myasthenia gravis.

Fiberoptic endoscopic evaluation of swallowing with simultaneous Tensilon application in diagnosis and therapy of myasthenia gravis

BACKGROUND

Dysphagia is a common symptom in myasthenia gravis (MG). Clinical examination alone fails to detect and grade myasthenic dysphagia sufficiently. For a more precise examination of swallowing function in myasthenia gravis additional technical tools are necessary.

OBJECTIVE

To investigate the diagnostic and therapeutic impact of fiberoptic endoscopic evaluation of swallowing with simultaneous Tensilon application (FEES-Tensilon Test) in myasthenia gravis.

METHODS

FEES-Tensilon Test was performed following a standardized protocol. Four severely affected patients with dysphagia as their leading symptom were examined. Dysphagia was characterized by five salient endoscopic findings: leakage, delayed swallowing reflex, penetration, aspiration and residues. If a normalisation or at least an improvement of swallowing function occurred shortly after Tensilon administration the FEES-Tensilon Test was rated as being positive.

RESULTS

In three patients the FEES-Tensilon Test successfully detected MG-related dysphagia. In one patient with dysphagia caused by oculopharyngeal muscular dystrophy the FEES-Tensilon Test was truly negative. Beside an early diagnosis of MG-related dysphagia, the FEES-Tensilon Test was useful in the differentiation between myasthenic and cholinergic crisis and in guiding treatment decisions. In all patients the FEES-Tensilon Test was superior to clinical evaluation of dysphagia. No severe side effect occurred while performing the FEES-Tensilon Test.

CONCLUSION

The FEES-Tensilon Test is a suitable tool in the diagnosis and therapy of myasthenia gravis with pharyngeal muscles weakness.