Source:http://linkedlifedata.com/resource/umls/id/C0179390
UMD: Slender surgical instruments designed for passing through thin anatomic tubular structures (e.g., ear canal, urethra, esophagus) for the purposes of calibrating and/or dilating the structure, guiding another instrument through the structure, or dislodging an object. These handheld, manual instruments are typically flexible, rod-shaped, frequently hollow cylinders of metal, plastic, or rubber; they come in a variety of shapes and diameters. Dedicated bougies are available with a variety of shapes at their distal tip, such as bulbous or olive-shaped. Some bougies allow the introduction of a filament with a very small caliber (i.e., a filiform) through the hollow core and/or include a balloon at the distal tip.