Читать книгу The Esophagus - Группа авторов - Страница 79

The chronic nature of OPD requires assessment of therapeutic results and progress with repeat video‐fluoroscopic study. Because of the radiation exposure and difficulty in moving some patients to the radiology suite, a videoendoscopic approach to the evaluation of OPD has been developed [70–73]. This technique also allows outpatient/clinic evaluation of dysphagic patients. In this technique, a small‐diameter endoscope, such as a laryngoscope or bronchoscope, is inserted through the nose and positioned at the level of the posterior nares. In this position, the patient is asked to swallow. During this swallow, normal features of the pharyngeal seal – the adduction of the superior constrictor and postero/orad elevation of the palate, seen as a bulging in the nasopharynx – are examined, and then the scope is advanced to the level of the free margin of the epiglottis. At this position, the glottis is clearly seen, and its adduction function is examined by having the patient produce different vowels. Following this, a 5–10 mL water bolus colored with blue food dye is given through the mouth, and the patient is instructed to hold the bolus in the mouth for 20 s. During this time, the back of the tongue is observed video‐endoscopically for the presence or absence of unilateral or bilateral spill or entry of colored water into the airway (pre‐deglutitive aspiration). The presence of spill is seen in patients with abnormalities of the tongue and/or palate control. Following this stage, the scope is withdrawn to the level of the posterior nares, and the patient is asked to swallow once. The scope is immediately advanced to the level of the epiglottis. On the way toward the epiglottis, attention is given to the presence or absence of blue staining of the retropalatal pharynx, indicative of nasal regurgitation due to abnormalities of the velopharyngeal closure mechanism. This abnormality may be caused by inadequate elevation and posterior movement of the soft palate and uvula. Then the inner aspect of the epiglottis, aryepiglottic fold, posterior commissure, and true vocal cords are examined for the presence or absence of staining. In a study of normal volunteers in our laboratory, only the outer edges of the epiglottis and aryepiglottic fold were stained with blue dye. Endotracheal coloring with blue dye is easily seen, proving aspiration. The patients are then asked to cough once; and, since during cough the laryngeal vestibule remains open, expulsion of blue material from the trachea can be seen and is indicative of aspiration. Following this phase, the presence or absence of residue in the pyriform sinus and vallecula is determined, and overflow of residue into the trachea through the posterior commissure is sought.