| macroscopic sphincter | A sphincter visible to the naked eye. (05 Mar 2000) |
|---|---|
| palatopharyngeal sphincter | A constant band of the superior pharyngeal constrictor muscle which sweeps posteriorly from the anterolateral part of the superior surface of the palatine aponeurosis. It creates a visible ridge when the superior constrictor is contracted, meeting the elevated soft palate to seal off the pharyngeal isthmus during swallowing. Synonym: pharyngeal ridge, sphincter of the pharyngeal isthmus, velopharyngeal sphincter. (05 Mar 2000) |
| radiological sphincter | A section of a tubular structure that acts as if it has a band of circular muscle to constrict it, although no such specialised structure can be found on morphological examination. Synonym: functional sphincter, radiological sphincter. (05 Mar 2000) |
| Varolius' sphincter | A thickening of circular musculature at the free margin of the ileal papilla. Synonym: ileocaecocolic sphincter, marginal sphincter, operculum ilei, Varolius' sphincter. (05 Mar 2000) |
| pancreatic sphincter | Smooth muscle sphincter of the main pancreatic duct immediately proximal to the hepatoduodenal, ampulla. Synonym: musculus sphincter ductus pancreatici, pancreatic sphincter, sphincter muscle of pancreatic duct. (05 Mar 2000) |
| velopharyngeal sphincter | A constant band of the superior pharyngeal constrictor muscle which sweeps posteriorly from the anterolateral part of the superior surface of the palatine aponeurosis. It creates a visible ridge when the superior constrictor is contracted, meeting the elevated soft palate to seal off the pharyngeal isthmus during swallowing. Synonym: pharyngeal ridge, sphincter of the pharyngeal isthmus, velopharyngeal sphincter. (05 Mar 2000) |
| marginal sphincter | A thickening of circular musculature at the free margin of the ileal papilla. Synonym: ileocaecocolic sphincter, marginal sphincter, operculum ilei, Varolius' sphincter. (05 Mar 2000) |
| rectosigmoid sphincter | <anatomy> A circular band of muscular fibres at the recto sigmoid junction. Synonym: O'Beirne's sphincter, O'Beirne's valve, pelvirectal sphincter. (05 Mar 2000) |
| Glisson's sphincter | The smooth muscle sphincter of the hepatopancreatic ampulla within the duodenal papilla. Synonym: musculus sphincter ampullae hepatopancreaticae, Glisson's sphincter, hepatopancreatic sphincter, Oddi's sphincter. (05 Mar 2000) |
| pathologic sphincter | A thickening of circular musculature caused by disease. (05 Mar 2000) |
| mediocolic sphincter | A physiological sphincter located midway in the ascending colon. (05 Mar 2000) |
| pelvirectal sphincter | <anatomy> A circular band of muscular fibres at the recto sigmoid junction. Synonym: O'Beirne's sphincter, O'Beirne's valve, pelvirectal sphincter. (05 Mar 2000) |
| choledochal sphincter | Smooth muscle sphincter of the common bile duct immediately proximal to the hepatopancreatic ampulla; it is this sphincter that controls the flow of bile in the duodenum. Synonym: musculus sphincter ductus choledochi, Boyden's sphincter, choledochal sphincter, sphincter muscle of common bile duct. (05 Mar 2000) |
| microscopic sphincter | A sphincter visible only under the microscope. (05 Mar 2000) |
| midgastric transverse sphincter | Angular sphincter, thickening of the circular muscular layer forming a proposed intermediate sphincter at the level of the angular notch of the stomach. While the thickening of the circular muscle may indicate the commencement of the pyloric antrum, true functional sphincteric activity distinct from the other peristaltic contractions of the stomach is not observed although some of these may in fact temporarily close off the antrum from the remainder of the stomach lumen. Synonym: antral sphincter, midgastric transverse sphincter, sphincter antri, sphincter intermedius, sphincter of antrum, sphincter of gastric antrum. (05 Mar 2000) |