Source:http://linkedlifedata.com/resource/umls/id/C0037816
NCI: An instrument used to widen an opening of the body to make it easier to look inside.,UMD: Mechanical instruments (retractors) designed to be used to separate the walls of a cavity to make examination and/or treatment possible. These instruments frequently include two pivoted arms. The portions closer to the pivot point are usually the handle, while the distal portions are inserted into the cavity; specula may be of many different sizes and shapes. When force on the specula handle is exerted, the blunt distal tips open the cavity. Other specula consist of hollow, funnel-like devices. Specula are used for examination and/or treatment through natural canals of internal tissues and/or organs of the human body that are otherwise inaccessible, frequently by inserting other instruments through them. Both reusable (typically made of stainless steel) or disposable (usually plastic) specula are available for many applications, and some include a lighting system.