Changes of Swallowing Function and Oropharyngeal Muscle Mass on Sonography After Comprehensive Swallowing Therapy and Neuromuscular Electrical Stimulation in Stroke Patients With Dysphagia

1. The inter-rater and intra-rater reliability of sonography.
2. To explore that sonography is a clinically practical tool for assessing the changes of oropharyngeal muscles mass.
3. The Comparisons the differences in clinical swallowing function, general muscle mass, and muscle strength/ sonographic findings of oropharyngeal muscles among the stroke patients with dysphagia in different swallowing training programs.
4. To investigate the associations among clinical swallowing function, general muscle mass, muscle strength and sonographic findings of oropharyngeal muscles in stroke patients with dysphagia.
5. The changes of clinical swallowing function, and muscle strength of oropharyngeal muscles in stroke patients with dysphagia after different swallowing training programs.
6. The changes in sonographic findings of oropharyngeal muscles in stroke patients with dysphagia after different swallowing training programs.
7. Effect of different swallowing therapies in clinical swallowing function, general muscle mass, and muscle strength/ sonographic findings of oropharyngeal muscles in stroke patients with dysphagia.
8. The associations between clinical swallowing function, oropharyngeal muscle strength, and sonographic findings of oropharyngeal muscles in stroke patients with dysphagia.

After acute stroke, 25∼45% of patients show difficulties in swallowing, which is associated with a high risk of pneumonia, malnutrition, and mortality. In addition to traditional swallowing therapies for post-stroke dysphagia (PSD), the Iowa Oral Performance Instrument (IOPI) is used to provide tongue exercise program which improving swallowing function. Additionally, neuromuscular electrical stimulation (NMES) is also beneficial to manage PSD. In rehabilitation unit, ultrasound is a convenient tool and is more widely used in investigating oropharyngeal muscles mass and quality in PSD. Therefore, the investigators hope to assess the effects on swallowing function and oropharyngeal muscle mass on sonography after IOPI swallowing training and neuromuscular electrical stimulation in PSD.

First, the investigators will enroll 20 normal people, whose ages should be from 40-80 years old, to verify the inter-rater and intra-rater reliability of sonography and use IOPI to assess maximal muscle strength and endurance of oropharyngeal muscles. Second, 40 stroke patients with different levels in dysphagia will be enrolled. Each patient will receive clinical assessments of swallowing and tongue functions, general and oropharyngeal muscles mass and quality by sonography, and life quality. These stroke patients with dysphagia will be randomly allocated in two groups. the investigators will provide two interventions including combined simple and IOPI therapies(n=20), and combined swallowing therapy with NMES(n=20) for the 2 groups.

The investigators will investigate the differences of swallowing and tongue functions, oropharyngeal muscles on sonography in patients with PSD. The effects of the swallowing therapies in swallowing function, oropharyngeal muscle mass, and life quality will be explored in PSD by using different swallowing therapies. The investigators will find out the most effective swallowing therapy from these 2 interventions for PSD. Furthermore, the investigators could explore that sonography is a clinically practical tool for assessing oropharyngeal muscles mass and quality in PSD.

Eligibility Criteria:
Normal group

Inclusion Criteria:

* The ages of participants should be from 40 to 80 years old.
* Normal people that are healthy and have no history of systemic diseases that are associated with swallowing difficulty.

Exclusion Criteria:

* Any other history of systemic diseases that are associated with swallowing difficulty.
* Aged younger than 40 or older than 80 years old

Intervention groups

Inclusion Criteria:

* Patients with stroke that are diagnosed with oropharyngeal dysphagia (FOIS1-4).
* The duration since the onset of stroke should be 2-6 months.
* The ages of participants should be from 40 to 80 years old.

Exclusion Criteria:

* The stroke duration is less than 2 months or more than 6 months after stroke
* Aged younger than 40 or older than 80 years old
* Any cognitive deficit that leads to communicative difficulty.
* Any other history of systemic diseases that are associated with swallowing difficulty.