Current and future techniques in the evaluation of dysphagia.

Dysphagia is common in the general population, and is generally due to either mechanical obstruction or dysmotility. Patient demographics and symptom evaluation are often useful in determining the likely cause, and guide subsequent investigation and management. Oropharyngeal dysphagia is usually caused by neurological conditions where treatment options are limited. Conversely, many of the esophageal causes of dysphagia are amenable to therapy. Gastroscopy is often the first test of choice, given its diagnostic and therapeutic potential, especially when mechanical causes are concerned. Esophageal motor function can be assessed by a variety of techniques, ranging from radiology such as barium swallow, to dedicated motility tests such as manometry and impedance monitoring. The choice of test relies on the clinical indication and the results should be interpreted in conjunction with the patients' symptoms. High-resolution manometry with topography is now the new benchmark for motility studies. Several new techniques for motility testing have also become available, such as esophageal ultrasound and functional lumen imaging probe, but are currently limited to the research setting.