Articles
Articles are a collaborative effort to provide a single canonical page on all topics relevant to the practice of radiology. As such, articles are written and continuously improved upon by countless contributing members. Our dedicated editors oversee each edit for accuracy and style. Find out more about articles.
786 results found
Article
Increased fetal renal echogenicity
Increased fetal renal echogenicity is a non-specific sonographic finding with no underlying cause seen in many cases, although it is a potential indicator of underlying disease due to the association with numerous pathologies (especially if accompanied by enlargement) 1:
chromosomal abnormaliti...
Article
Fetal atrioventricular block
Fetal atrioventricular block is a form a fetal bradyarrhythmia often classified into
fetal partial atrioventricular block (PAVB)
fetal complete atrioventricular block (CAVB)
Epidemiology
Fetal atrioventricular block is considered rare finding with reported occurrences of around 1:11,000-20,0...
Article
Fetal urinary bladder
The fetal urinary bladder, also known as the bladder bubble, is visible as an anechoic cyst on ultrasound in most fetuses from 12-13 weeks of gestation 1.
The size of the bladder is denoted by measuring the longitudinal bladder diameter from superiorly to inferiorly in the sagittal plane. Age-r...
Article
Fetal breathing movements
Fetal breathing movements (FBM) are episodic rhythmic contractions of the diaphragm and other muscles of respiration.
Fetal breathing may be noticed as early as 15 weeks of gestation. At 24 -28 weeks, the fetus breaths about 10-20% of the time, increasing to 30% at 30 weeks of pregnancy 1. Feta...
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
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
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
Intrathymic left brachiocephalic vein
Intrathymic left brachiocephalic vein is a common variant that can often be seen during fetal ultrasound. Instead of coursing posterior to the thymus, the left brachiocephalic vein courses through the thymus 1.
It is considered a normal variant and is believed to have no adverse effects on the...
Article
Footling presentation
A footling presentation (sometimes termed an incomplete breech presentation) is a variation in fetal presentation and is considered a form of breech presentation. It is uncommon and thought to account for around 10-30% of births. In this presentation the fetus has a longitudinal lie but has one ...
Article
Normal imaging examples
This article lists examples of normal imaging divided by body region and system.
brain
head and neck
spine
chest
breast
gastrointestinal
genitourinary
hepatobiliary
upper limb
lower limb
pediatrics
Article
Enhanced myometrial vascularity
Enhanced myometrial vascularity (EMV), often misdiagnosed as an acquired uterine arteriovenous malformation, is the presence of transiently increased blood flow within the uterine myometrium, typically associated with complications of pregnancy.
Terminology
Somewhat confusingly, the term “enh...
Article
Cervical cerclage
Cervical cerclage is a treatment that is undertaken during pregnancy to reduce the chances of preterm labor. It involves the placement of a suture around the neck of the cervix. It aims to reduce the risk of preterm birth and provides mechanical support to keep the cervix closed 1,2.
Cervical c...
Article
Symphyseal fundal height
Symphyseal fundal height (SFH) is commonly used measurement practiced primarily used to detect fetal intrauterine growth restriction (IUGR).
For fetuses after 24 weeks' gestation, it is measured using a tape as the distance
from
- the pubic symphysis (by identifying the upper border of the sy...
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
Frog eye sign
The frog eye sign is seen when the orbital structures show a characteristic protrusion due to fetal anencephaly. The term is particularly used in point of care ultrasound (POCUS) 1.
Radiographic features
On obstetric ultrasound the frog eye sign is best appreciated in the coronal plane (in re...
Article
Quadruple screening test
The quadruple screening test, also known as the quad screen, AFP Plus quad test or multiple marker screening test, is a maternal antenatal screening blood test that can be used in conjunction with other investigations e.g. ultrasound soft markers, to estimate the risk of aneuploidy 1.
This is ...
Article
The crisscross sign
The crisscross sign is a fetal ultrasound sign that describes the normal relationship between the ventricular outflows tracts of the fetal heart. The left ventricular outflow tract (LVOT); represented by the take-off of the aorta (Ao) from the left ventricle, is perpendicular (90o) to the right ...
Article
Adenomyomatous endometrial polyp
An adenomyomatous polyp of the endometrium is a rare form of endometrial polyp and comprises of a pedunculated lesion that contains smooth muscle in addition to the usual components of an endometrial polyp. On outer examination, they may be difficult to differentiate from ordinary endometrial po...
Article
Precipitous labor
Precipitous labor, also known as precipitous birth, is labor that happens too quickly, and is formally defined as fetal expulsion three hours or less after the start of regular uterine contractions. Contradictory and somewhat limited data demonstrates a higher risk of pregnancy-related complicat...
Article
Forceps delivery criteria (mnemonic)
A mnemonic to remember the criteria for forceps delivery is:
FORCEPS
Mnemonic
F: fetus alive
O: os dilated
R: ruptured membrane / rotation complete
C: cervix take-up
E: engagement of head
P: presentation suitable
S: sagittal suture in AP diameter of inlet
Unable to process the form. Check for errors and try again.