1. Undulating folds or valves in the proximal mucosa of the cystic duct. (wikipedia.org)
2. A series of crescentic folds of mucous membrane in the upper part of the cystic duct, arranged in a somewhat spiral manner. (biology-online.org)
Syn: plica spiralis ductus cystici, Amussat’s valve, Heister’s valve, spiral valve of cystic duct, spiral fold of cystic duct, valvula spiralis.