title: Four-dimensional ultrasonography of a true knot of the umbilical cord.
abstract: We describe the prenatal diagnosis of a true knot of the umbilical cord using the "hanging noose" sign. Changes in the tension of the knot, which are related to fetal movements, were studied with 4-dimensional ultrasonography.
authors.affiliation: Prenatal Diagnosis Unit, Service of Obstetrics and Gynecology, Hospital Xeral, Pontevedra, Spain. clopezr@meditex.es
authors.forename: Carlos López
authors.initials: CL
authors.lastname: Ramón y Cajal
authors.forename: Raquel Ocampo
authors.initials: RO
authors.lastname: Martínez
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D011247:Pregnancy; D018608:Ultrasonography, Doppler; D016216:Ultrasonography, Prenatal; D014470:Umbilical Cord / Q000002:abnormalities* / Q000000981:diagnostic imaging*