syncytial knot


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syn·cy·tial knot

a localized aggregation of syncytiotrophoblastic nuclei in the villi of the placenta during early pregnancy.

syncytial knot

A multinucleated aggregate of syncytial nuclei at the surface of terminal villi in the placenta, which is rarely seen under 20 weeks of gestation. In term placentas, most syncytial knots are regarded as artefacts of tangential sectioning; the minority are syncytial sprouts, bridges, or apoptotic knots. They are consistently present, increasing with gestational age, and can be used to evaluate villous maturity.

Syncytial knots are associated with uteroplacental malperfusion (maternal diabetes, hypertension, pre-eclampsia and anaemia) and are an important datum in placental examination. In placentas without a history of malperfusion or clinical conditions associated with malperfusion, at 20 to 25 weeks, syncytial knots average 7%; at 26 to 33 weeks, 13%; at 36 weeks, 22.5%; at term, 37 to 40 weeks, term placentas have an average of 28% syncytial knots.

syncytial knot

Obstetrics A multinucleated protrusion from the trophoblastic surface which is commonly found in later pregnancy, excessively so in post-term gestation. See Chorionic villi. Cf Syncytial bud, Syncytial sprout.

syn·cy·tial knot

(sin-sish'ăl not)
A localized swelling or aggregation of syncytiotrophoblastic nuclei in the villi of the placenta during early pregnancy.
Synonym(s): nuclear aggregation.
References in periodicals archive ?
Syncytial knots were found in all placentas but they were considerably more at decreasing levels of maternal hemoglobin (19.
Keywords: Low hemoglobin concentration, Placental infarcts, Placental morphology, Placental weight, Syncytial knots.
Rathod KB, Jaiswal KN et al (2007) (11) showed pathological changes of placenta in the form of infarction, calcification, increased syncytial knots.
Descriptive morphological characterization of syncytial knots shed in vitro from first trimester placenta [abstract].
Syncytial knots are seen with increased frequency in the last weeks of pregnancy and more villi show these changes in high risk pregnancies.
HISTOPATHOLOGICAL CHANGESIN ASPIRIN GROUP ABSENT MINIMAL CYTOTROPHOBLASTIC PROLIFERATION 56% 44% SYNCYTIAL KNOTS 68% 32% BASEMENT MEMBRANE THICKENING 72% 28% FIBRINOIDNECROSIS 84% 16% MEDIAL HYPERTROPHY 76% 24% OLD INFARCTS 92% 08%
VILLOUS OBSERVATION IN PIH CASES HISTOPATHOLOGICAL CHANGES MILD SEVERE CYTOTROPHOBLASTIC PROLIFERATION 72% 28% SYNCYTIAL KNOTS 64% 36% BASEMENT MEMBRANE THICKENING 30% 26% MEDIAL HYPERTROPHY 38% 30% FIBRINOID NECROSIS 28% 24% OLD INFARCTS 36% 44%
The number of areas of Syncytial knots in PIH group (70.
Syncytial knots are consistently present, increasing with increasing gestational age, and can be used to evaluate villous maturity.