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
Hydrops fetalis
Hydrops fetalis is excessive fluid into the third space in a fetus, which could be due to heart failure, volume overload, decreased oncotic pressure, or increased vascular permeability.
Epidemiology
The estimated incidence is ~1 in 2000 pregnancies 16 and ~1 in 1000 live births 17, although th...
Article
Pre-eclampsia
Pre-eclampsia is a disorder of pregnancy involving new-onset hypertension (systolic BP ≥140 mmHg or diastolic BP ≥90 mmHg) and involvement of one or more other organ systems.
Epidemiology
Pre-eclampsia affects up to 8% of pregnancies 1.
Risk factors
diabetes mellitus 2
chronic hypertension ...
Article
Placentomegaly
Placentomegaly is a term applied to an abnormally enlarged placenta.
Epidemiology
Associations
It can be associated with several maternal and fetal disorders:
maternal
maternal anemia(s)
maternal diabetes
chronic intrauterine infections
alpha-thalassemia
fetal
umbilical vein obstructio...
Article
Renal agenesis
Renal agenesis refers to a congenital absence of one or both kidneys. If bilateral (traditionally known as the classic Potter syndrome) the condition is fatal, whereas if unilateral, patients can have a normal life expectancy.
Epidemiology
Unilateral renal agenesis affects approximately 1 in ...
Article
Fetal tricuspid regurgitation
Tricuspid regurgitation (TR) (also known as tricuspid insufficiency) is a common finding in imaging of the fetus. Tricuspid regurgitation represents the abnormal backflow of blood into the right atrium during right ventricular contraction due to valvular leakage (i.e. it is a valvulopathy).
Ep...
Article
Chiari III malformation
Chiari III malformation is an extremely rare anomaly characterized by a low occipital and high cervical encephalocele with herniation of posterior fossa contents, that is, the cerebellum and/or the brainstem, occipital lobe, and fourth ventricle.
Pathology
Associations
agenesis of the corpus...
Article
Fetal bowel dilatation
Fetal bowel dilatation can occur from many causes, which include:
intestinal atresias: mainly distal
anal atresia
apple-peel intestinal atresia
ileal atresia
jejunal atresia
jejuno-ileal atresia
Hirschsprung disease
megacystis microcolon hyperperistalsis syndrome 4
congenital chloride d...
Article
Isolated inferior vermian hypoplasia
Isolated inferior vermian hypoplasia (IIVH) is a congenital malformation characterized by partial absence of the inferior portion of the cerebellar vermis.
Terminology
Previously the term Dandy-Walker variant was used to describe cystic malformations of the posterior fossa that did not meet th...
Article
Monochorionic twin pregnancy
A monochorionic twin pregnancy is a type of monozygotic twin pregnancy where the twins share a single chorion. Depending on the sharing of the amnion this can be further divided into two types:
monochorionic monoamniotic (MCMA) pregnancy: single amnion
monochorionic diamniotic (MCDA) pregnancy...
Article
Monozygotic twin pregnancy
A monozygotic (MZ) twin pregnancy results from the division of single zygote following fertilization, resulting in identical genetic material. These twins are therefore always of the same sex.
Epidemiology
Monozygotic twins account for approximately 30% of all twin pregnancies 1. The estimated...
Article
Twin-to-twin transfusion syndrome
Twin-to-twin transfusion syndrome (TTTS), less commonly known as stuck twin syndrome, is a potential complication that can occur in a monochorionic twin pregnancy (either MCDA or MCMA).
Epidemiology
This complication can occur in ~10% (range 15-25%) of monochorionic pregnancies, giving an est...
Article
Congenital megaureter
A congenital (primary) megaureter encompasses causes of an enlarged ureter which are intrinsic to the ureter, rather than as a result of a more distal abnormality; e.g. bladder, urethra (see secondary megaureter). It includes:
obstructed primary megaureter
refluxing primary megaureter
althoug...
Article
Non-invasive perinatal testing (NIPT)
Non-invasive perinatal testing (NIPT) is an antenatal screening technique that relies on the detection of small amounts of cell-free fetal DNA to be detected in the maternal bloodstream, hence allowing prenatal genetic diagnosis to occur by way of a maternal blood test. It can be performed from ...
Article
Ovarian vein thrombosis
Ovarian vein thrombosis (actually most often thrombophlebitis) occurs most commonly in postpartum patients and can result in pulmonary emboli. A presentation is usually with acute pelvic pain in the postpartum period, then termed puerperal ovarian vein thrombosis or postpartum ovarian vein throm...
Article
Congenital pulmonary airway malformation
Congenital pulmonary airway malformations (CPAM) are multicystic masses of segmental lung tissue with abnormal bronchial proliferation. CPAMs are considered part of the spectrum of bronchopulmonary foregut malformations.
Terminology
Until recently, they were described as congenital cystic aden...
Article
Placental infarction
Placental infarction refers to a localized area of ischemic villous necrosis. It is a significant cause of placental insufficiency.
Epidemiology
A localized infarction can occur in up to ~25% of all placental pathologies and approximately 5-20% of all gestations (on average 12.5%) 6.
Pathol...
Article
Barth syndrome
Barth syndrome (BTHS), also known as 3-methylglutaconic aciduria type II, is an extremely rare X-linked multisystem disorder that is usually diagnosed in infancy.
Epidemiology
Barth syndrome has an estimated prevalence of 1 in 300,000-400,000 live births.
Clinical presentation
It is characte...
Article
Roberts syndrome
Roberts syndrome, also known as Roberts-SC phocomelia syndrome, pseudothalidomide syndrome, or Appelt-Gerken-Lenz syndrome, is a rare congenital malformation syndrome.
Clinical presentation
general
intrauterine growth restriction
postnatal growth and developmental delay
failure to thrive
t...
Article
Megalencephaly
Megalencephaly is a disorder characterized by an abnormally large brain. It is primarily a proliferative disorder of embryonic origin. It may involve all or part of the cerebral hemispheres and can be bilateral or unilateral. It is often associated with polymicrogyria or agyria.
Terminology
...
Article
Lowe syndrome
Lowe syndrome, also known as the oculocerebrorenal syndrome of Lowe, is a multisystem disorder characterized by anomalies primarily affecting the eyes, nervous system, and kidneys.
Epidemiology
It is an extremely rare, pan-ethnic disease, with an estimated prevalence in the general population ...
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