Masterclass 7 - Advancements In Diagnosis and Treatment of Oropharyngeal Dysphagia: A Multidisciplinary Approach

Oropharyngeal dysphagia, or swallowing impairment, is a common condition impacting approximately one in five adults each year. Dysphagia can arise as the result of numerous medical conditions such as stroke, neurodegenerative diseases, and head and neck cancer. The consequences of oropharyngeal are significant and may include malnutrition and dehydration, aspiration pneumonia, and death. Additionally, there is a substantial socioemotional toll of oropharyngeal dysphagia, often leading to social isolation and depression. As a result of the substantial impact of oropharyngeal dysphagia, management of this complex disorder is of paramount importance to the medical community and society at large. In recent years, there has been an increased interest in harnessing the power of technology to optimize the prevention and rehabilitation of oropharyngeal dysphagia. In this session, we will discuss currently available technological adjuncts and biofeedback devices that can be integrated into dysphagia rehabilitation to optimize patient outcomes.

Dysphagia (swallowing disorders) is prevalent among patients with stroke and other neurological diseases such as Parkinson's disease and Huntington's disease. It can result in devastating consequences including malnutrition, dehydration, aspiration pneumonia, prolonged hospital stays and increased mortality rate secondary to aspiration pneumonia. However, to date, there is a lack of effective treatment for dysphagia. One of the key factors for functional recovery of swallowing following neurological damage is neuroplasticity, which is the ability of the nervous system to change in response to intrinsic and extrinsic stimuli. Recent studies suggested that neurostimulation treatments, including pharyngeal electrical stimulation (PES), repetitive transcranial magnetic stimulation (rTMS), and transcranial direct current stimulation (tDCS), have shown great potential in promoting neuroplasticity in the swallowing system, particularly among stroke patients.
In this talk, I will first review the current evidence on the clinical efficacy of dysphagia treatments. Then I will present findings on the effects of neurostimulation treatments (PES, rTMS and tDCS) on swallowing functions in patients with neurogenic dysphagia. Finally, I will highlight some challenges in using neurostimulation as a dysphagia treatment and discuss how we can translate the research findings into clinical practice.

Investigation of swallowing physiology and swallowing problem (dysphagia) have mainly been conducted by fluoroscopic, endoscopic and electrophysiological examinations that focus on the movements of structures, or contraction of superficial muscles. The muscle morphometry, deeper muscular movement and the pressure generated by them, important factors in safety and efficiency of swallow, have not been extensively investigated until the emergence of two tools in oropharyngeal dysphagia management.
Ultrasound (USG) has a long history in diagnostics and rehabilitation. In dysphagia management, it has been mostly used to measure tissue morphometry and swallowing kinematics, among others. It has the advantage of being non-invasive and portable, suitable for use in clinic and in-patient settings. HRPM with impedance is able to reveal the dyanmic action of the pharynx, upper esophageal sphincter and the esophagus in conjunction with bolus flow. It has the advantage of being able to provide quantitative data on various consistencies of liquid and food. Normative data are also becoming more available for comparison in recent years.
Measurements by USG and HRPM have been demonstrated to be associated with events that affect the safety and efficiency of swallowing, such as residue and aspiration events. They are becoming more common as diagnostic tools or tools for measuring treatment outcome.
In this presentation, updated literature on USG and HRPM will be presented. In particular, a HRPM protocol and metrics proposed by an international working group and its application in local context will be discussed. The presentation will also feature selected cases highlighting the use of USG and HRPM in clinical context, how it was able to facilitate decision making and measuring treatment outcomes. The implication of how USG and HRPM will affect dysphagia management will also be briefly discussed.