A lateral video X-ray that provides objective information on bolus transport, safest consistency of bolus, and possible head positioning and maneuvers that may facilitate swallow function depending on each individual's anatomy and physiology. Esophagogastroduodenoscopy – a diagnostic endoscopic procedure that visualizes the upper part of the gastrointestinal tract. Esophageal motility study – a test to assess motor function of the upper and lower esophageal sphincter as well as the esophageal body.