Swallowing Function in Patients With Head and Neck Cancers
Condition: Head Neck Cancer; Oral Cancer
MeSH terms: Head and Neck Neoplasms; Mouth Neoplasms
Study type: Interventional

Summary: 
      Head and neck cancer (HNC) is the sixth most common cancer worldwide, accounting for 2.8% of
      all malignancies. The presence of tumor itself, as well as the treatment, can result in
      neuromuscular damage affecting any stage of the swallowing. Organ-sparing care has become
      more common in recent years, however, that this does not always imply functional
      preservation. Dysphagia and aspiration both can occur and can have complex causes. Normal
      swallowing has oral preparatory phase, pharyngeal phase, and the oesophageal phase, it is
      important to know what is the dysfunction and where. This study aim to evaluate the
      preoperative and postoperative swallowing function in patients with head neck cancer using
      electromyography (EMG) and video fluoroscopy.
    

Detailed description: 
      The process of swallowing includes the conscious effort to ingest food and a subconscious or
      reflex effort of bolus preparation. The preparation of the bolus is referred to as the
      preparatory phase, the transport of the bolus from the oral cavity and pharynx to the
      oesophagus as the transport phase and through the oesophagus as the oesophageal transport
      phase. The rhythm and pattern of the swallowing mechanism is controlled by a central pattern
      generator located in the medulla.

      The tongue plays an important role in the preparatory phase by mixing the food and moving it
      towards the occlusal surface of the teeth. Sensory innervation across the oral mucosa and the
      tone of the facial muscles help in keeping the bolus within the oral cavity and in its
      manipulation. The soft palate approximates to the tongue to create a glossopalatal seal which
      prevents premature spillage in to the pharynx, while various movements of the mandible are
      imperative for the adequate grinding of the bolus. The tongue then contracts from anterior to
      posterior pushing the bolus back into the pharynx, the whole process taking about one second.
      This phase involves the Vth, VIIth and XIIth cranial nerves.

      The pharyngeal phase is involuntary, with sensations travelling through the IXth and Xth
      cranial nerves and usually lasting one second. In this phase, the soft palate closes the
      nasopharynx, the larynx is elevated and closed, the pharyngeal constrictors contract and the
      cricopharynx relaxes. The true cords, the false cords, the epiglottis and the aryepiglottic
      folds constrict to form a barrier of several layers preventing aspiration.

      The mechanism varies and there is no gold standard test that can accurately measure this
      dysfunction. Most patients are investigated only when it impairs the feeding and nasal
      feeding tubes are required. It is not know as to how much the function preserving
      conservative surgeries actually preserve the function and hence, the importance of this
      study.
    

Intervention name(s): Surface Electromyography and Video fluoroscopy
Intervention type(s): Diagnostic Test
Intervention description(s): Surface EMG of three muscle groups (masseter, submental, and infrahyoid) and video fluoroscopy with Omnipaque
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Diagnostic
Keywords: Swallowing; Aspiration; Surgery; treatment; Dysphagia