standard BS or upper gastrointestinal (UGI) series in that it does not use pure contrast, but instead uses food mixed with contrast in an attempt to simulate the normal feeding pattern as closely as possible VFSS is less effective than a UGI series or BS at diagnosing gastroesophageal reflux or lower esophageal, gastric outlet, and small bowel abnormalities ( Fig 56.3 ), but it is superior in identifying pre-esophageal causes of dysphagia Fiberoptic endoscopic evaluation of swallowing (FEES) has also been used as the diagnostic and clinical tool for the pediatric dysphagia patient With a nasopharyngeal approach under local anesthesia, FEES allows direct visualization of the swallowing process with the ability to document aspiration and functional pharyngeal or upper esophageal disorders FEES may also be indicated for the suspected mass lesion, stricture, caustic ingestion, inflammatory lesion, or foreign body FEES has been successfully used to initially screen dysphagia patients, and to reevaluate swallowing function after feeding interventions to patient diet and position, as well as food presentation Fiberoptic endoscopic evaluation of swallowing with sensory testing (FEESST) is a modification of FEES and is a test of the laryngeal adductor response (LAR) and vocal cord dynamics for assessment of the motor and sensory phases of swallowing It is an alternative test to VFSS with the benefits of being nonradioactive and can be done in the office setting This test is especially useful in decreasing aspiration pneumonia by dietary and behavioral management of patients with swallowing problems Other tests, such as a complete blood cell count and blood, urine or CSF cultures in the febrile patient, or blood gas for the patient with respiratory distress, may also be indicated Cervical ultrasonography has been used to identify abnormalities with the tissues and function of the palate, tongue, and floor of the mouth; however, it is less useful than contrast studies for assessing airway problems and aspiration