Swallowing Science Lecture Notes

Vocabulary flashcards for swallowing science lecture review.

Normal Swallow

Occurs approximately 500 times a day and serves the purpose of nutrition, but carries risks like aspiration.

Anatomy of Swallow

The oral cavity, oropharynx, pharynx, larynx, and esophagus.

Oral Cavity

Includes teeth, lips, sulcus, buccal and labial areas, tongue, hard and soft palate, faucial pillars, and tonsils.

Pharynx

Includes the nasopharynx, oropharynx, and hypopharynx.

OroPharynx

Includes the base of the tongue, valleculae, and superior & middle pharyngeal constrictors.

HypoPharynx

Includes the inferior pharyngeal constrictor, pyriform sinuses, and cricopharyngeus.

Larynx

Includes the epiglottis, false vocal folds, true vocal folds, and is part of the upper airway.

Esophagus includes

Includes the upper esophageal sphincter (cricopharyngeus) and the lower esophageal sphincter.

Swallow Phases

Includes oral prepatory, oral, pharyngeal, and esophageal phases.

Oral Prepatory Phase

The positioning phase where the tongue arranges the bolus, moves it posteriorly for chewing by molar teeth, reduces it through grinding, mixes it with saliva, and forms the bolus.

Oral Phase

Primarily a delivery system where the bolus is transported via the tongue/palate/teeth. The velum elevates, lips contract , posterior tongue lowers, and the anterior/middle tongue elevate to propel the bolus to the oropharynx.

Pharyngeal Phase

Begins when the bolus reaches the Anterior Tonsillar (faucial) Pillars and includes tongue tip elevation, velopharyngeal closure, elevation of larynx, activation of cricopharyngeus, movement of bolus, and is an involuntary phase.

Esophageal Phase

The muscular tube, 20-25 cm in length, with peristalsis, which shortens by 10% during swallow through longitudinal muscle contraction.

Linguapalatal valve

Pressure that contains the bolus in the oral cavity.

Velopharyngeal valve

Closure to prevent nasal regurgitation.

Laryngeal sphincter

Closes anteriorly & laterally providing 3 layers of protection which include vocal folds close, false vocal folds close and Epiglottis inverts.

Upper Esophageal Sphincter

Separates the pharynx from the esophagus, with the Cricopharyngeus as a major component. It minimizes air in digestive tract and prevents reflux into the pharynx. It is activated during the pharyngeal phase to relax and open for 1 second.

Lower Esophageal Sphincter

Located in the distal esophagus, in a tonic state at rest, and prevents GER (gastroesophageal reflux). Relaxes when activated during swallow and is influenced by hormones & chemicals.

Rationale for Modified Barium Study (MBS)

To examine the anatomy and physiology of all stages of swallow; to quantify the risk of aspiration; identify swallowing strategies and diet textures that facilitate safe swallows.

Fluoroscopy

A technique for obtaining dynamic x-ray images using a radiopaque table, fluoroscopy tube, monitor, and control room.

Cinefluoroscopy

Allows for slow motion and provides sharper images but exposes patients to higher radiation and is difficult to record sound.

Digital Video Recording

Cheaper, requires less radiation, can be played back immediately, and allows for voice recording.

MBS Necessary Supplies

Liquid barium, thickener, pudding barium (e.g. Esophatrast, Varibar), shortbread cookies, disposable plastic, syringe, cups, spoons, straws.

MBS - The Procedure

Sit upright or stand in a lateral or anterior-posterior view. Patient is provided consistencies coated in barium: thin liquid, thick liquid, pudding, and cookie in bolus volumes of 2-3 swallows at each volume of 1ml, 3 ml, 5ml, and 10ml.

Radiographic view - lateral

Lips, soft palate, posterior pharyngeal wall, and 7th cervical vertebrae.

Clinician Radiation Safety

Wear a lead apron, lead thyroid shield, lead-lined gloves, radiation badge, and stand behind a lead shield.

Oral Transit Time (OTT)

Time it takes the bolus to move through the oral cavity from the first frame showing backward movement of bolus until the bolus tail passes the anterior faucial arch. Increases with age and bolus consistency with normal OTT < 1.5 sec.

Pharyngeal Transit Time

Time it takes the bolus to move through the pharynx, < 1 sec.

Pharyngeal Delay Time

The time between swallow stimulation & activation. From the time the bolus head arrives at faucial pillars & tongue base until the pharyngeal swallow is triggered. Increases with age, but not with bolus volume.

Esophageal Transit Time

Time it takes the bolus to move through the esophagus. Varies with the bolus volume and consistency and is usually between 8 to 20 sec.

What should you observe?

Strength of swallow, Bolus cohesion, Bolus propulsion, Pooling/Residue, Cough

What should you observe?

Sensation, Response to residue, Response to laryngeal penetration, Aspiration Risk (silent vs sensate)

What should you observe?

Anatomic & Physiologic abnormalities such as Base of Tongue, Velopharyngeal competence, Laryngeal elevation, Epiglottic inversion, Laryngeal Closure, Cricopharyngeal opening

Lateral view during MBS

Better view of anatomy: Oral & Nasal Cavities, Base of tongue, Vallecule, Velum, Epiglottis, Larynx, Pyriform sinuses

Anterior-Posterior view during MBS

Better view of bilateral anatomy: Oral & Nasal Cavity, Valleculae, Pyriform sinuses.

Disorders in Oral Preparation

Reduced labial strength/closure, Bolus leak out of mouth, Reduced range of tongue motion or lingual coordination, Residue in oral cavity, Pocketing in Sulci, Premature spill into pharynx

Disorders of Oral Phase

Decreased lingual strength/ROM, Residue hard palate, Residue base of tongue, Decreased bolus cohesion during propulsion, Premature Pooling in Valleculae

Swallow Initiation Disorders

Delayed swallow initiation, Decreased bolus cohesion, Pooling in Valleculae, Bolus in pharynx/larynx before laryngeal elevation

Pharyngeal Phase Disorders

Inadequate velopharyngeal closure (Nasal regurgitation), Inadequate laryngeal elevation (Absent or reduced epiglottic inversion, Residue in valleculae), Decreased Cricopharyngeal opening.

Pharyngeal Phase Disorders

Inadequate laryngeal closure, Laryngeal penetration, Aspiration, Inadequate cricopharyngeal opening, Residue in pyriform sinus