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Circummarginate placenta

Circummarginate placenta is an uncommon variation in placental morphology. The chorionic membranes insert inward from the margin of placental edge, similar to circumvallate placenta, but unlike circumvallate placenta, the placental edge is not thickened and rolled up, and there is no central dep...

Basal plate

The basal plate is a synonym for the maternal side of the placenta. The fetal side of the placenta is termed the chorionic plate. Some pathologies and processes are localized to the basal plate, and evaluation of the basal plate is a part of placental grading.

Chorionic plate

The chorionic plate is a synonym for the fetal side of the placenta. The maternal side of the placenta is termed the basal plate. Some pathologies and processes are localized to the chorionic plate, and evaluation of the chorionic plate is a part of placental grading.

Increased fetal abdominal circumference

Increased fetal abdominal circumference is usually given when the abdominal circumference lies above the 90th percentile. During the second and especially the third trimester, an increased abdominal circumference usually contributes to a high estimated fetal weight (large for dates fetus), which...

Neurenteric canal of Kovalevsky

The neurenteric canal or canal of Kovalevsky is the transient communication of the amnion through notochordal canal to the yolk sac during notochordal formation at day 16-17. Abnormalities during this stage produce the neurenteric cyst spectrum.

Kinked brainstem

Kinking of the brainstem is a rare finding in fetal or pediatric neuroimaging, invariably seen in association with other cerebral abnormalities. It generally heralds a poor neurological outcome. Clinical presentation A kinked brainstem may be seen on fetal MRI, commonly after referral from ult...

Amniotic fluid in the first trimester

Amniotic fluid in the first trimester has been estimated from weeks 7-12. Although the amniotic fluid index (AFI) is calculated in the second trimester, one can get an idea of whether the amount of amniotic fluid is too much or too little at an earlier time point. The amniotic fluid volume is r...

Vitamin B9

Vitamin B9 (folate or folic acid) is a water-soluble vitamin, part of the vitamin B complex, vital for the synthesis of several amino acids, the purines adenosine and guanine and the pyrimidine thymine (three of the four nucleotide bases and hence critical for the synthesis of nucleic acids). T...

Ductus arteriosus

The ductus arteriosum (DA) (or arteriosus) is the thick short conduit for blood to bypass the non-ventilated lungs in the fetus. It is located between and connects the proximal left pulmonary artery and the undersurface of the aortic arch distal to the origin of the last branch of the arch, at t...

Foramen ovale (cardiac)

The foramen ovale (or ovalis) is the opening in the interatrial septum in the fetal heart that allows blood to bypass the right ventricle and non-ventilated lungs, shunted from the right atrium to the left atrium. Specifically it represents the opening between the upper and lower portions of th...

Broad ligament

The broad ligaments (TA: ligamentum latum uteri or plica lata uteri 4) are the paired lateral folds of the parietal peritoneum which reflect over the upper genital tract in females. Gross anatomy The broad ligament extends from the lateral aspect of the uterus to the lateral pelvic wall and ca...

Anatomy curriculum

The anatomy curriculum is one of our curriculum articles and aims to be a collection of articles that represent the core anatomy knowledge for radiologists and imaging specialists. General anatomy Neuroanatomy Head and neck anatomy Thoracic anatomy Abdominal and pelvic anatomy Spinal anat...

Snowstorm sign (disambiguation)

Snowstorm sign may refer to: snowstorm sign: complete hydatiform mole (ultrasound) snowstorm sign: extracapsular breast implant rupture (ultrasound) snowstorm sign: thyroid pulmonary metastases (chest radiograph)

Terminal myelocystocele

Terminal myelocystoceles are an uncommon form of spinal dysraphism representing marked dilatation of the central canal of the spinal cord, herniating posteriorly through a dorsal spinal defect. The result is a skin-covered mass in the lower lumbar region, consisting of an ependyma-lined sac. E...

Asymmetric ventriculomegaly, interhemispheric cyst and dysgenesis of the corpus callosum (AVID)

Asymmetric ventriculomegaly, interhemispheric cyst, and dysgenesis of the corpus callosum (AVID) is a triad of congenital cerebral anomalies. Radiographic features markedly asymmetric enlargement of the lateral ventricles may be the initial finding on routine fetal morphology ultrasound. inte...

Absent yolk sac

Absence of the yolk sac in the presence of an embryo on a transvaginal ultrasound is considered abnormal, and in general is associated with subsequent embryonic death. See also yolk sac

Endometrial reflectivity (ultrasound grading)

Endometrial reflectivity grading on ultrasound is a system initially proposed by Smith et al. in 1984 which classifies the endometrium into four types according to the echotexture pattern. They are considered to be useful in deciding on receptivity in in-vitro fertilisation (IVF). The Smith sys...

Cerebroplacental ratio

Cerebroplacental ratio (CPR) is an obstetric ultrasound tool used as a predictor of adverse pregnancy outcome in both small for gestational age (SGA) and appropriate for gestational age (AGA) fetuses. An abnormal CPR reflects redistribution of cardiac output to the cerebral circulation, and has ...

Placenta fenestrata

Placenta fenestrata is one of the variations in placental morphology, which is characterized by one or more areas of focal placental atrophy lacking villi and covered only by the chorion membrane.

Large yolk sac

A large yolk sac is one measuring >5-6 mm in pregnancies between a gestational age of 5-10 weeks. One study had shown that a yolk sac diameter of >5 mm can be associated with an increased risk of spontaneous miscarriage although few other authors have mentioned the existence of a very large yolk...

Small yolk sac

A small yolk sac is considered a non-specific feature and, at the time of writing, there are not many publications about the clinical importance of small yolk sacs. According to some publications, a very small yolk sac may be a normal finding during early periods of normal embryologic developme...

Parapagus

Parapagus twins are conjoined twins that lie side-by-side with ventrolateral fusion. This type of conjoined twins usually shares the umbilicus, abdomen, and pelvis. The conjoined pelvis may have a single symphysis pubis and one or two sacra. The lower gastrointestinal tract (single colon and...

Cephalopagus

Cephalopagus twins are a rare type of conjoined twins. They are fused from the vertex to the umbilicus. They share a common cranium with either one composite face or two faces on opposite sides of the conjoined head. The thoraces are fused with fusion of liver, heart, and the upper gastrointest...

Rachipagus

Rachipagus twins are an extremely rare type of conjoined twins. They are joined in the dorsal aspect and face away from each other. Fusion of the occiput with varying segments of the vertebral column may occur, resulting in the sharing of the spinal cords. The fusion terminates above the sacrum...

Craniopagus

Craniopagus twins are conjoined twins that are fused at any part of the skull, except the face, foramen magnum, skull base and the vertebral column. The fused structures are most often the cranium, meninges, and dural venous sinuses. Brains tend to be separate; however, they may be connected by...

Pygopagus

Pygopagus twins are conjoined twins that are joined in the dorsal aspect, facing away from each other. They share the sacrococcygeal and perineal regions. Fusion of sacrum and coccyx frequently occurs. The dura and the spinal cords may be fused in as many as 1/3rd of the cases. The anus, rectum...

Thoracopagus conjoined twins

Thoracopagus conjoined twins are, as the name suggests, conjoined twins united at their thorax. Thoracopagus and thoraco-omphalopagus form the most common forms of conjoined twins 3. Fusion is typically face-to-face, at the upper thorax to the umbilicus with a common sternum, diaphragm, and upp...

Omphalopagus

Omphalopagus twins are joined at the front and at the level of the umbilicus. Commonly involved structures are lower thorax fusion and liver fusion. Pericardium may be common, but the heart is never shared. Stomach and the proximal small intestines are usually separate but the small intestines ...

Cervical incompetence morphological changes on ultrasound (mnemonic)

Sequential morphological ultrasound changes of the endocervical canal with cervical incompetence can be remembered using the mnemonic: Trust Your Vaginal Ultrasound Mnemonic T-shaped (normal internal cervical os) Y-shaped V-shaped U-shaped Related article cervical incompetence funnelin...

Non-invasive perinatal testing (NIPT)

Non-invasive perinatal testing (NIPT) is an antenatal screening technique that has relatively recently come into practice. It 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...

Intramembranous ossification

Intramembranous ossification describes the process of ossification from mesenchymal cells (stem cells) without a cartilaginous template and is involved in the healing process of fractures. The stages of intramembranous ossification osteogenesis are as follows: mesenchymal cells differentiate in...

Ductus venosus

Ductus venosus (DV) is a narrow, trumpet-shaped vessel which is seen in the fetal liver connecting the umbilical vein directly to the caudal inferior vena cava or distal left hepatic vein. The vessel plays a critical role in the fetal circulation by shunting oxygenated and nutrient-rich umbilica...

Three vessel and trachea view

The three vessel and trachea view (also known as 3VT view or arrow view) is one of the fetal echocardiography views. In this view, aortic and ductal arches are combined into the descending aorta and appear as a V-shaped confluence. Both arches tend to be of similar size and are located towards...

Umbilical artery

The umbilical artery gives rise to both a nonfunctional remnant of the fetal circulation and an active vessel giving supply to the bladder. In the adult, the obliterated area of the vessel is identifiable as the medial umbilical ligament and the patent segment is the superior vesical artery. Su...

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...

Pregnancy with intrauterine contraceptive device

Pregnancy with intrauterine contraceptive device (IUCD) is uncommon and an IUCD is a highly effective contraception method. Chances of pregnancy to occur is highest during the first year of IUCD usage and there are chances of adverse outcomes during pregnancy. Terminology The preferred abbrevi...

Complete hydatidiform mole with coexistent fetus

Complete hydatidiform mole with coexistent fetus is an extremely rare entity where there is a twin pregnancy with a complete hydatidiform mole and a normal fetus. Epidemiology It is seen extremely rarely, with an estimated incidence of 1 in 10,000–100,000 pregnancies 5. Clinical presentation...

Multiple placental cysts

Multiple placental cystic spaces can be seen in many conditions: within the placenta venous lakes true placental cysts allantoic ducts cysts hydropic degeneration of placenta placental mesenchymal dysplasia adjacent the placenta subchorionic/retroplacental hematoma subamniotic hematomas...

Placental mesenchymal dysplasia

Placental mesenchymal dysplasia (PMD) is a rare, benign condition that is characterized by enlargement of the placenta with multiple bunches of grape-like vesicles that can resemble a molar pregnancy by ultrasound and gross pathologic examination. Epidemiology This is an often underdiagnosed ...

Placental shelf

A placental shelf refers to a ridge of placental tissue freely abutting the margin. It may represent part of a circumvallate placenta, although an early second-trimester placental shelf can be a common, benign and transient finding 1. Placental shelves detected in early second-trimester are tho...

Absent septum pellucidum

An absent septum pellucidum may rarely be an isolated finding, or more commonly be seen in association with a variety of conditions. Epidemiology The septum pellucidum is partly or entirely absent in 2 or 3 individuals per 100,000 in the general population. Pathology An absent septum pelluc...

Embryonic growth discordance

Embryonic growth discordance is a term given to a twin growth discordance occurring during the early embryonic period. It is principally manifested by a discrepancy in crown rump length. It is considered independent of the chorionicity of the twins 5. Epidemiology Embryonic growth discordance...

Uterine artery pseudoaneurysm

Uterine artery pseudoaneurysm (UAP) is a rare cause of secondary postpartum hemorrhage. Clinical presentation UAP usually presents as delayed (secondary) postpartum hemorrhage, that is per vaginal bleeding which occurs more than 24 hours and up to 6 weeks postpartum. However, some reported ca...

Umbilical cord hematoma

Umbilical cord hematoma describes the formation of a hematoma secondary to bleeding from the umbilical cord. Pathology The hematomas can be either spontaneous or iatrogenic. Spontaneous bleeding is very rare and documented to be around 0.02% of pregnancies. Majority of the cases are iatrogenic...

Hanging noose sign

Hanging noose sign in obstetric imaging is a rarely described but classical finding of a true umbilical cord knot. It demonstrates a transverse section of the umbilical cord surrounded by a loop of umbilical cord and changes in the pressure of the knot can be demonstrated with the fetal movement...

False umbilical cord knot

False umbilical cord knots are commonly formed variants in the anatomy of the umbilical cord. It basically represents an exaggerated looping of the umbilical cord vessels, causing focal dilatation of the umbilical cord vessels. Radiographic features Ultrasound bulge or protuberance in the umb...

True umbilical cord knot

True umbilical cord knots are a rare occurrence and as the name suggests represent a knot formation in the umbilical cord. Epidemiology They occur in less than 1% of pregnancies. Pathology Risk factors a long umbilical cord polyhydramnios small fetus excessive fetal movements Radiograph...

Retroplacental complex

Retroplacental complex (RPC) is the region behind the placenta and is composed of decidua basalis and portions of myometrium including the maternal veins which drain the placenta. Radiographic features Ultrasound visualized after 20 weeks of gestation seen as an hypoechoic, subplacental regi...

Intrauterine membrane in pregnancy

An echogenic membrane might be seen within the uterus during pregnancy: membrane of maternal origin uterine septum amniotic shelf intrauterine synechiae membrane of fetal origin intertwin membrane amniotic band chorioamniotic separation chorioamniotic elevation fibrin strand

Straight umbilical cord

Straight umbilical cord implies, as the name suggests, an umbilical cord with no coils. Epidemiology The reported incidence of a straight cord is about 3.7-5% of all pregnancies. Radiographic features Ultrasound the entire length of the umbilical cord shows no evidence of coiling Complicat...

Right ventricular outflow tract view (fetal echocardiogram)

The right ventricular outflow tract (RVOT) view (or three vessel view/3VV) is one of the standard views in a fetal echocardiogram. It principally assesses the right ventricular outflow tract. It is a long axis view of the heart, highlighting the path from the right ventricle into the pulmonary t...

Left ventricular outflow tract view (fetal echocardiogram)

The left ventricular outflow tract (LVOT) view (or five chamber view) is one of the standard views in a fetal echocardiogram. It is a long-axis view of the heart, highlighting the path from the left ventricle into the ascending aorta (left ventricle outflow tract). In this view, the right vent...

Isolated inferior vermian hypoplasia

Isolated inferior vermian hypoplasia (IIVH), also referred as part of Dandy-Walker variant (DWV), is a congenital malformation characterized by partial absence of the inferior portion of the cerebellar vermis. Terminology The term Dandy-Walker variant was created to include those malformations...

Lethal omphalocele-cleft palate syndrome

Lethal omphalocele-cleft palate syndrome is, as the name suggests, characterized by the association of omphalocele and cleft palate. Prevalence is assumed to be <1 per 1,000,000. It has been postulated that this syndrome is likely to be an autosomal recessive condition 1. History and etymolog...

Pseudo-omphalocele

Pseudo-omphalocele is a spurious sonographic appearance giving an impression of an anterior abdominal wall defect. Radiographic features Antenatal ultrasound Pseudo-omphalocele may be seen in: scanning errors where there is a deformation of the fetal abdomen by transducer pressure and the im...

Echogenic yolk sac

An echogenic yolk sac is an indeterminate finding in first-trimester fetal ultrasound. It differs from a calcified yolk sac, in that the contents of the yolk sac are echogenic, not just the rim. One study has suggested that this finding is associated with fetal demise, but other reports in the ...

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...

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 ...

Induced fetal demise

Induced fetal demise as the name suggests, refers to an iatrogenically-induced fetal demise, most often by injection of a pharmacologic agent. Indications selective or non-selective reduction of one of the fetuses in a multifetal pregnancy fetal demise is often induced before medical or surgi...

The Pre-Conception and Pre-Natal Diagnostic Techniques (Prohibition Of Sex Selection) Act

The Pre-Conception and Pre-Natal Diagnostic Techniques (Prohibition Of Sex Selection) Act (PCPNDT) is a statute enacted to stop the female feticide that has resulted in declining female sex ratio in India. As per census 2011, adult sex ratio in India is 943 females per 1000 males and child sex...

Fetal head sparing theory

The fetal head sparing theory is one that underpins asymmetrical intra-uterine growth restriction, where the difference between normal head circumference and decreased abdominal circumference is attributed to the fetus's ability to preferentially supply the cerebral, coronary, adrenal and spleni...

Triple screening

Triple screening refers to a screening blood test that is used to screen pregnant women for possible neural tube defects, Down syndrome and trisomy 18 in the developing fetus. It measures: alpha-fetoprotein beta hCG unconjugated estriol Interpretation An abnormal test result doesn't indica...

Pregnancy-associated plasma protein-A

Pregnancy-associated plasma protein-A (PAPP-A) is a protein found in the maternal circulation and is produced by the placenta. The PAPP-A gene has been assigned to human chromosome 9q33.1 and contains 22 exons 5. PAPP-A values tend to rise exponentially during pregnancy and the reference range d...

Corpus luteal cyst rupture

Ruptured corpus luteal cysts are one of the commonest causes of spontaneous hemoperitoneum in a woman of reproductive age. Clinical presentation Presentation is variable, ranging from completely asymptomatic to severe abdominal pain due to peritoneal irritation. Pathology The corpus luteum i...

Expanded amnion sign

The expanded amnion sign has been described as a poor prognostic sign in early pregnancy, suspicious though not diagnostic of failed early pregnancy. Any visible embryo that is surrounded by an amnion (visible on transvaginal ultrasound) should also have a heartbeat, regardless of crown-rump len...

Fetal ventriculomegaly (differential)

Fetal ventriculomegaly (ventricle width >10 mm) is an important finding in itself and it is also associated with other central nervous system abnormalities. For more information, see the main article fetal ventriculomegaly. Differential diagnosis Fetal ventriculomegaly can be thought of in ter...

Snake under the skull sign

Snake under the skull sign is a vascular anomaly seen in holoprosencephaly. Pathology Due to the defect in the cleavage of the two hemispheres there is a fusion of the frontal lobes. This band of abnormal cortical tissue causes forward displacement of the anterior cerebral artery, so that it l...

Placental evaluation with MRI

Placental evaluation with MRI is a problem-solving technique that can be used if ultrasound evaluation is insufficient or confusing. Even if the placenta is not the main point of evaluation, it is useful to understand the appearance of the placenta on obstetric imaging for other causes. Techniq...

Bandl ring

A Bandl ring may be seen during imaging of a patient in labor. Epidemiology It is considered to be an uncommon finding in modern obstetrics (0.01-1.26%). Pathology It is a pathologic retraction ring at "Barnes boundary line", which separates the upper contractile portion of the uterus from l...

Fetal middle cerebral artery pulsatility index

The fetal middle cerebral artery (MCA) pulsatility index (PI) is a key parameter used in fetal middle cerebral arterial Doppler assessment. It is calculated by subtracting the end-diastolic velocity (EDV) from the peak systolic velocity (PSV) and then dividing by the time-averaged (mean) velocit...

3D ultrasound

Three-dimensional (3D) ultrasound is a technique that converts standard 2D grayscale ultrasound images into a volumetric dataset. The 3D image can then be reviewed retrospectively. The technique was developed for problem-solving (particularly in obstetric/gynecologic exams) and to potentially re...

Beta-hCG

Beta-hCG (bHCG or β-hCG) is a sex hormone found in the mother's blood serum that can be used to help interpret obstetric ultrasound findings. Beta-hCG levels may be used in three ways in the clinical setting of pregnancy: qualitatively, for presence/absence of fetal tissue more often determin...

Rhombencephalon

The rhombencephalon (plural: rhombencephalons or rhombencephala), or hindbrain is a primary vesicle of the neural tube. Development During the fifth week of embryological development, the rhombencephalon further subdivides into the secondary brain vesicles, the metencephalon and the myelenceph...

Calcified yolk sac

A calcified yolk sac has been described as a sign of intrauterine demise. The cause of yolk sac calcification in failed pregnancies is uncertain but is likely related to dystrophic calcification. Radiographic features Ultrasound abnormal increased echogenicity of the yolk sac with posterior a...

Preplacental abruption

Preplacental abruption or hemorrhage can be subamniotic or subchorionic in location. Clinical presentation vaginal bleeding most often painless Symptoms may be similar to placental abruption in other locations, however, it may not have as poor a prognosis as other forms of placental abruptio...

Marginal placental abruption

Marginal placental abruption is the most common type of placental abruption wherein a hematoma is located, as the name suggests, in the margin of the placenta and the blood collects below the chorionic membrane. It is most often seen in placentae that are partially implanted in the lower uterine...

Bladder flap hematoma

Bladder flap hematoma is a hematoma between the uterus and posterior wall of urinary bladder. They may be small (more commonly) or large (>5 cm, less common). Clinical presentation Small hematomas may be asymptomatic. Large ones may present with lower abdominal pain, dysuria, anemia and fever ...

Amelia

Amelia refers to a skeletal dysplasia characterized by the complete agenesis of an upper or lower extremity or all four limbs. It may be associated with other congenital anomalies, i.e. omphalocele and diaphragmatic hernias 3. Epidemiology Amelia is a very rare congenital anomaly with an incid...

Cephalopelvic disproportion

Cephalopelvic disproportion (CPD) occurs when there is a mismatch between the size of the fetal head and the maternal pelvis causing a difficulty in the safe passage of the fetus through the birth canal. Pathology Cephalopelvic disproportion may be caused by the fetal head outgrowing the capac...

Dystocia of shoulder

Shoulder dystocia (SD) refers to the failure of the shoulder to be delivered during childbirth and the need for extra-obstetric maneuvers to facilitate their passage after normal smooth gentle downward traction has failed. Dystocia literally means difficult labor. Epidemiology The incidence of...

Small gestational sac

A small gestational sac in early first trimester is considered a poor prognostic factor. Some authors use the mean sac diameter to crown rump length difference of 5 mm or greater to be normal 1. The smaller than expected sac diameter in pregnancies 36-42 days from the last menstrual period ha...

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...

Double outlet left ventricle

Double outlet left ventricle (DOLV) is an extremely rare congenital cardiac anomaly where both the aorta and pulmonary trunk arise from the anatomical left ventricle. It is usually classified as a conotruncal anomaly and is often associated with a ventricular septal defect with normal continuity...

Fetal circulation

Fetal circulation differs from the adult circulation due to the presence of certain vessels and shunts. These shunts close after birth, and most of the fetal vessels are visible as remnants in the adult circulation. The function of these shunts is to direct oxygen-rich venous blood to the syst...

Cystic hygroma vs occipital meningocele

Cystic hygroma and occipital meningocele are both differential diagnosis for an antenatally detected cystic collection noted on the posterior aspect of the head and neck. A simple differentiation can be made based on the contents and presence of septations: cystic hygroma will present as a wel...

Acrania anencephaly sequence

Acrania anencephaly sequence or acrania–exencephaly–anencephaly sequence is the progression from a relatively normal-appearing exposed brain due to an absent cranium (acrania) to an amorphous brain mass (exencephaly) to no recognisable brain tissue (anencephaly) 1. Epidemiology The acrania ane...

Femur length (obstetric ultrasound)

Fetal femur length (FL) is a basic biometric parameter to assess fetal size. Femur length, together with biparietal diameter, head circumference, and abdominal circumference, are computed to produce an estimate of fetal weight. In the second trimester, this may be extrapolated to an estimate of ...

Fetal abdominal circumference

Abdominal circumference (AC) is one of the basic biometric parameters used to assess fetal size. AC together with biparietal diameter, head circumference, and femur length are computed to produce an estimate of fetal weight. In the second trimester, this may be extrapolated to an estimate of ges...

Head circumference

Head circumference (HC) is one of the basic biometric parameters used to assess fetal size. HC together with biparietal diameter (BPD), abdominal circumference (AC), and femur length (FL) are computed to produce an estimate of fetal weight. In the second trimester, this may be extrapolated to an...

Biparietal diameter

Biparietal diameter (BPD) is one of the basic biometric parameters used to assess fetal size. BPD together with head circumference (HC), abdominal circumference (AC), and femur length (FL) are computed to produce an estimate of fetal weight. In the second trimester this may be extrapolated t...

Trauma in pregnancy

Trauma is a leading cause of mortality in pregnancy. Pregnancy increases the incidence and severity of abdominal trauma in females. Epidemiology Trauma affects up to 7% of pregnancies, and the incidence of pregnancy in level 1 trauma patients is estimated to be ~2% 1. Pathology Etiology 9...

Fetal chylothorax

Fetal chylothorax is defined as the presence of lymphatic fluid within the pleural cavity of the fetus. Pathology Associations pulmonary hypoplasia hydrops fetalis premature delivery Radiographic features Antenatal ultrasound may show echogenic fluid in the pleural cavities Treatment S...

Fetal MCA systolic/diastolic ratio

Fetal MCA systolic/diastolic (S/D) ratio is an important parameter in fetal middle cerebral arterial Doppler assessment. It is a useful predictor of fetal distress and intrauterine growth restriction (IUGR). Interpretation Normal During pregnancy the middle cerebral (and other intracranial)...

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