Articles
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45 results found
Article
Lambda sign (disambiguation)
There are two described lambda (λ) signs:
lambda sign (twin pregnancy)
lambda sign (sarcoidosis)
Article
Butterfly sign (choroid plexus)
The butterfly sign refers to the normal appearance of the choroid plexuses on axial imaging of the fetal brain, commonly observed on the antenatal ultrasound. Its absence may suggest holoprosencephaly 1.
In the CNS, the term should not be confused with a butterfly glioma, which is a glioblastom...
Article
Amniotic fluid sludge (ultrasound)
Amniotic fluid sludge is a finding in obstetric transvaginal ultrasound scanning. Defined as free-floating hyperechogenic material in close proximity to the cervical internal os within the amniotic cavity of women with intact fetal membranes 1. It images as a dense, homogenous mass 2.
Pathology...
Article
Abnormally eccentric gestational sac
An eccentrically-located gestational sac towards the fundus of the uterus is the normal sonographic appearance, however, an abnormally eccentric gestational sac on ultrasound may be apparent due to a number of causes:
interstitial ectopic pregnancy 1
normally implanted pregnancy in a
bicornu...
Article
Chorionic bump
Chorionic bump is a finding that can be uncommonly seen in a first-trimester scan. It may represent a small hematoma bulging into the gestational sac or an anembryonic (failed) second pregnancy that is being resorbed. It is also seen in some patients undergoing infertility treatment.
Epidemiolo...
Article
Interstitial line sign
The interstitial line sign is an ultrasound finding in interstitial ectopic pregnancy. It is an echogenic line from the mass to the endometrial echo complex. Reportedly it has high sensitivity (80%) and specificity (98%).
Article
Yolk stalk sign
The yolk stalk sign is the abnormal sonographic finding when an embryo with a crown-rump length of ≤ 5 mm without heartbeat is separated from the yolk sac. It is suspicious but not diagnostic of a failed early pregnancy. In early embryonic development, the embryo is typically adjacent to the dev...
Article
Congenital hallux valgus
Congenital hallux valgus is a very rare finding wherein a fetus or newborn shows lateral deviation of the first toe(s). When found on prenatal imaging, bilateral congenital/foetal hallux valgus is highly suggestive of fibrodysplasia ossificans progressiva 1,2.
See also
hallux valgus
Article
Fetal maceration
Fetal maceration is one of the signs of fetal death. It is a destructive process caused by enzymatic autolysis of cells that begins immediately following fetal death. It results in epidermal desquamation and edema. It is visible on ultrasound between 12 to 24 hours after fetal death. It may not ...
Article
T sign (disambiguation)
The T sign has been described in several different pathologies:
T sign (obstetrics)
T sign (elbow MRI)
upper T sign (brain)
lower T sign (brain)
See also
tau sign
Article
T sign (obstetrics)
The T sign is really the absence of a twin peak sign (or lambda (λ) sign) and is used in ultrasound assessment of a multifetal pregnancy.
It refers to the lack of chorion extending between the layers of the intertwin membrane, denoting a monochorionic pregnancy. The intertwin membrane comes to ...
Article
Tubal ring sign
The tubal ring sign, also referred to as a bagel sign or blob sign, is one of the ultrasound signs of a tubal ectopic pregnancy. It comprises an echogenic ring that surrounds an unruptured ectopic pregnancy. It is said to have a 95% positive predictive value (PPV) for ectopic pregnancy.
Differe...
Article
Echogenic fetal bowel
Echogenic fetal bowel is an observation in antenatal ultrasound imaging, in which fetal bowel appears to be brighter than it is supposed to be. It is a soft marker for trisomy 21 and has several other associations. When observed, it needs to be interpreted in the context of other associated abno...
Article
Cloverleaf skull (craniosynostosis)
Cloverleaf skull, also known as kleeblattschädel syndrome or deformity, refers to a type of severe craniosynostosis that gives the skull a cloverleaf shape. It is very rare, with less than 130 case reports globally. It typically results from intrauterine premature closure of the sagittal, corona...
Article
Twin peak sign
The twin peak sign, also known as the lambda (λ) sign, is the triangular appearance of the chorion insinuating between the layers of the intertwin membrane and strongly suggests a dichorionic diamniotic twin pregnancy. It is best seen in the first trimester (between 10-14 weeks) 5. While the pre...
Article
Bladder vessel sign
Bladder vessel sign refers to the visualization of tortuous flow voids on MRI traversing space between the urinary bladder and the uterus (vesicouterine space); which normally contains fat and is devoid of blood vessels.
The sign is seen in the case of placenta accreta spectrum disorders, where...
Article
Bunch of grapes sign (disambiguation)
Bunch of grapes sign refers to the imaging appearance of multiple cystic spaces or lesions and it has been described for multiple pathologies:
bunches of grapes sign (hepatic abscess) 8
bunch of grapes sign (botryoid rhabdomyosarcoma) 5
bunch of grapes sign (bronchiectasis) 3
...
Article
Snowstorm sign (complete hydatiform mole)
Snowstorm sign in obstetric imaging is classically seen in complete hydatiform mole. It is characterized by the presence of many hydropic villi which gives the ultrasonographic appearance of a central heterogeneous mass having a solid, hyperechoic area and interspersed with a multitude of cystic...
Article
Mickey Mouse sign (anencephaly)
The Mickey Mouse sign in obstetric ultrasound denotes the characteristic "floating appearance" of the fetal cerebral lobes due to the absence of the cranium due to anencephaly.
Radiographic features
The sign is best seen in the coronal plane (in relation to the fetal head), where the cerebral...
Article
Banana sign (cerebellum)
The banana sign is one of the many notable fruit inspired signs.
This sign is seen on axial imaging through the posterior fossa of fetuses with associated conditions such as Chiari II malformation and/or spina bifida.
In Chiari II malformation, the banana sign describes the way the cerebellum...
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