The Effect of Pharyngeal Electrical Stimulation on Peripheral Biomechanical Aspects of Deglutition (PES)

Inclusion Criteria volunteers: Healthy volunteers can participate in this study if they: Are aged between 18 and 80 years old Have no (history of) chronic disease/medication altering the gastrointestinal (GI) motility Have no (history of) gastric or gastrointestinal surgery (except appendectomy and cholecystectomy) Have no (history of) gastrointestinal disease or chronic GI symptoms (heartburn, indigestion/dyspepsia, bloating and constipation) Have FOIS score 7 or BEDQ score <10 at baseline Provide witnessed written informed consent prior to any study procedure And if they do not meet any of the exclusion criteria listed below. Exclusion Criteria volunteers: Healthy volunteers will be excluded if they: Are aged <18 years or >80 years Have (any history of) a chronic disease/medication altering the GI motility Have (any history of) gastric or gastrointestinal surgery (except appendectomy and cholecystectomy) Have (any history of) gastrointestinal disease or chronic GI symptoms (heartburn, indigestion/dyspepsia, bloating and constipation) Have a FOIS score <7 or a BEDQ score ≥ 10 at baseline Fail to provide witnessed written informed consent prior to any study procedure Inclusion Criteria patients: Dysphagic stroke patients are eligible for study participation if they: Are admitted to the hospital because of first ever acute stroke (acute means assessment within one month post stroke onset) Hemorrhagic and ischemic stroke Supratentorial and infratentorial stroke Are aged between 18 and 80 years old Are medically stable, alert or arousable Have clinical (oropharyngeal) dysphagia well identified using the FOIS/DSRS/ BEDQ/PAS at baseline. In line with earlier studies, we use the following criteria: a DSRS score of 6 or higher; or a FOIS-score equal to or lower than 5; or a BEDQ score of 10 or higher or (when no oral food intake is possible and DSRS score is 12/FOIS score is 1) a PAS-score of 4 or higher Give (or have a witness to give) voluntary written informed consent And if they do not meet any of the exclusion criteria listed below. Exclusion Criteria patients: Patients will be excluded from study participation if: They are aged <18 years or >80 years They have an additional condition (e.g. advanced dementia) or diagnosis of a progressive neurological disorder or neuromuscular disorder that may explain dysphagia They have normal swallowing at baseline assessed with FOIS/DSRS/BEDQ/PAS They participate in any other study potentially influencing the outcome of PES, both medicinal or medical device product related and for which the patient signed a consent form for his/her study participation They receive or have received within one month prior to the intended PES treatment any form of non-invasive brain stimulation or percutaneous electrical stimulation therapy to treat dysphagia. (This is no issue, since this type of treatment is not performed at University Hospitals Leuven (UZ Leuven). It is not possible to pass a standard nasogastric tube, for example, nasal, oral or pharyngeal anatomical abnormalities that preclude passage of a feeding tube, oral intubation, history of oesophageal perforation, stricture or pouch They have a cardiac or respiratory condition that might render the insertion of a catheter into the throat unsafe (Atrial fibrillation does not render the insertion of a catheter unsafe) They have a permanently implanted electrical device They are pregnant They present with an oropharyngeal infection. This should be treated and resolved before the PES catheter is inserted They require a magnetic resonance imaging (MRI) scan during PES treatment. Insertion of the PES catheter should either be delayed until such time as the MRI has been completed, or the PES catheter should be removed and discarded and a new catheter inserted after the MRI is completed