Swallowing problems can be related to many causes including anatomic obstruction (e.g. cancer), neurologic disease (e.g. stroke), infection (e.g. candida), reflux, muscle tone problems, diabetes, alcoholism, vitamin deficiency, foreign bodies, caustic ingestion, aging, and many other possibilities. The swallowing mechanism is complex and any disorder affecting from the tongues to the stomach can create swallowing difficulties. In addition to the routine head and neck exam studies such as esophagoscopy (direct view of the esophagus), Barium swallow (x-ray observation of dye being swallowed, pH probe (detects acid reflux), and manometry (monitors muscle coordination and swallowing), may be ordered by the physician and swallowing therapist to assist in diagnosis and treatment. Patients may require comprehensive video testing (video stroboscopy) to determine the underlying pathology of voice disorder.