Fetal abdomen

7/19/2011

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Ultrasound EvaluationOf the Fetal AbdomenUltrasound EvaluationOf the Fetal Abdomen

Fetal Abdomen

Of the Fetal AbdomenOf the Fetal Abdomen

Director of Ultrasound Research & Education

Geisinger Medical Center

Danville, Pennsylvania

Mani Montazemi, RDMS

Current Official Practice GuidelineCurrent Official Practice Guideline

• Abdomen

– Anterior abdominal wall

– Cord insertion

Stomach

• Abdomen

– Anterior abdominal wall

– Cord insertion

Stomach

Fetal Abdomen

– Stomach• Presence, size, situs

– Kidneys

– Bladder

– Number of umbilical cord vessels

– Stomach• Presence, size, situs

– Kidneys

– Bladder

– Number of umbilical cord vessels

Scanning Tips Scanning Tips

Fetal Abdomen

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Fetal StomachFetal Stomach

• Wide range of shapes– Round to oval to kidney-shaped

• Wide range of sizes– 4mm to 4cm

• Wide range of shapes– Round to oval to kidney-shaped

• Wide range of sizes– 4mm to 4cm

Fetal Abdomen

• Variable filling and emptying– Based on fetal swallowing and peristalsis

• Variable filling and emptying– Based on fetal swallowing and peristalsis

Non-visualization of the StomachNon-visualization of the Stomach

• < 19 wks, 50% ABNL

• > 19 wks, 100% ABNL

• < 19 wks, 50% ABNL

• > 19 wks, 100% ABNL

Fetal Abdomen

Esophageal AtresiaEsophageal Atresia

Fetal Abdomen

Ecografia

Highlight

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• Incidence – 1 in 2500 to 4000 live births

• Overall detection rate – only 50%– Most of the polyhydramnios occur after 24 weeks

S ll h b bbl ld b di i d b i

• Incidence – 1 in 2500 to 4000 live births

• Overall detection rate – only 50%– Most of the polyhydramnios occur after 24 weeks

S ll h b bbl ld b di i d b i

Fetal Abdomen

– Small stomach bubble could be dismissed as being normal

– Small stomach bubble could be dismissed as being normal


• Small stomach depend on the type of esophageal atresia

• 5 types - most common with

• Small stomach depend on the type of esophageal atresia

• 5 types - most common with

Fetal Abdomen

yptracheoesophageal fistula– Fluid may cross the fistula

– Gastric secretions may accumulate

yptracheoesophageal fistula– Fluid may cross the fistula

– Gastric secretions may accumulate


• High incidence of additional anomalies > 50%– Cardiac, other GI, GU track,

CNS, Facial, skeletal, T18/21

• 40 % have IUGR

• High incidence of additional anomalies > 50%– Cardiac, other GI, GU track,

CNS, Facial, skeletal, T18/21

• 40 % have IUGR

Fetal Abdomen

• Incidence three times higher in twins

• Classic findings– Polyhydramnios

– Absent or small stomach bubble

• Incidence three times higher in twins

• Classic findings– Polyhydramnios

– Absent or small stomach bubble

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Non-visualization or Always Small Stomach (< 1cm)

Non-visualization or Always Small Stomach (< 1cm)

Causes:• High Gastrointestinal obstruction

– Mouth to esophagus

• Narrow/compressed chest

Causes:• High Gastrointestinal obstruction

– Mouth to esophagus


Fetal Abdomen


• Thoracic or neck mass

• Swallowing disorders

• Defect or mass in the fetal mouth (clefts)

• Severe neurologic or muscular abnormalities


• Thoracic or neck mass

• Swallowing disorders

• Defect or mass in the fetal mouth (clefts)

• Severe neurologic or muscular abnormalities

What do you see?What do you see?

Fetal Abdomen

Duodenal ObstructionDuodenal Obstruction

Fetal Abdomen

Large, obstructed stomach and a distended proximal duodenumLarge, obstructed stomach and a distended proximal duodenum

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• Two cystic structures in the abdomen that communicate with each other– Classic “double bubble”

• Two cystic structures in the abdomen that communicate with each other– Classic “double bubble”

Fetal Abdomen


• Can be seen as early as 22 weeks, usually it’s not apparent up until 29-32 weeks

• Polyhydramnios after 24 weeksDetection rate only 50%

• Can be seen as early as 22 weeks, usually it’s not apparent up until 29-32 weeks

• Polyhydramnios after 24 weeksDetection rate only 50%

Fetal Abdomen

– Detection rate = only 50%

• Associated with a 30% incidence of trisomy 21

• Associated with VACTERL complex

– Detection rate = only 50%

• Associated with a 30% incidence of trisomy 21

• Associated with VACTERL complex

VACTERL ComplexVACTERL Complex

Vertebral defects

Anal atresia

Cardiac defects

Vertebral defects

Anal atresia

Cardiac defects

Fetal Abdomen

Tracheoesophageal fistula

Esophageal atresia

Renal anomalies

Limb defects

Tracheoesophageal fistula

Esophageal atresia

Renal anomalies

Limb defects

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Duodenal ObstructionMajority of cases are due to mechanical problems

Duodenal ObstructionMajority of cases are due to mechanical problems

• Intrinsic causes – structural abnormalities

– Atresia (42%) • half of all duodenal atresias occur with Down syndrome, although

conversely, few cases of Down syndrome have duodenal atresia

Diaphragmatic web (10%)

• Intrinsic causes – structural abnormalities

– Atresia (42%) • half of all duodenal atresias occur with Down syndrome, although

conversely, few cases of Down syndrome have duodenal atresia

Diaphragmatic web (10%)

Fetal Abdomen

– Diaphragmatic web (10%)

– Stenosis (38%)

• Extrinsic causes – external cause

– Annular pancreas

– Malrotation

– Ladd’s bands

– Diaphragmatic web (10%)

– Stenosis (38%)

• Extrinsic causes – external cause

– Annular pancreas

– Malrotation

– Ladd’s bands


• Prognosis is dependent upon whether other anomalies are present and their severity

• Prognosis is dependent upon whether other anomalies are present and their severity

Fetal Abdomen

Polyhydramnios is a constant feature in all intestinal atresiaPolyhydramnios is a constant feature in all intestinal atresia

Fetal Abdomen

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Ventral Wall DefectsVentral Wall Defects

Omphalocele– Central defect– Associated anomalies are common– High risk of aneuploidy

Omphalocele– Central defect– Associated anomalies are common– High risk of aneuploidy

Gastroschisis– Periumbilical defect– Associated anomalies are uncommon– Little to no risk of aneuploidy– High rate of bowel related

complications

Gastroschisis– Periumbilical defect– Associated anomalies are uncommon– Little to no risk of aneuploidy– High rate of bowel related

complications

Fetal Abdomen

complications– Associated with substance abuse &

medications

complications– Associated with substance abuse &

medications

OmphaloceleOmphalocele

Fetal Abdomen

• Herniation of intraabdominal contents into the base of the cord

• ALWAYS covered by a membrane


• Umbilical cord inserts onto membrane– In large defects may be displaced eccentrically

• The herniated bowel is NOT directly exposed to amniotic fluid

• Umbilical cord inserts onto membrane– In large defects may be displaced eccentrically

• The herniated bowel is NOT directly exposed to amniotic fluid

Fetal Abdomen

• Bowel usually does not thicken or dilate• Bowel usually does not thicken or dilate

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Is This an Omphalocele?Is This an Omphalocele?

Fetal Abdomen

Pseudo-OmphalocelePseudo-Omphalocele

Fetal Abdomen

Caused by scanning oblique or by excessive transducer pressureCaused by scanning oblique or by excessive transducer pressure

OmphaloceleCan be a small or large wall defect

OmphaloceleCan be a small or large wall defect

Fetal Abdomen

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• Small– Failure of normal midgut rotation

– Cord midpositioned

Us all contains onl bo el

• Small– Failure of normal midgut rotation

– Cord midpositioned

Us all contains onl bo el

Fetal Abdomen

– Usually contains only bowel

– Associated with chromosomal anomalies

– Usually contains only bowel

– Associated with chromosomal anomalies


• Large– Failure of anterior abdominal

wall closure

– Cord eccentric

• Large– Failure of anterior abdominal

wall closure

– Cord eccentric

Fetal Abdomen

Cord eccentric

– May contain organs

– Scoliosis

– Associated with structural anomalies

Cord eccentric

– May contain organs

– Scoliosis

– Associated with structural anomalies


Measurements of AC inaccurate and should

Fetal Abdomen

inaccurate and should be excluded from

biometric calculations

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• IUGR has been reported in 20% of patients

• 50% have associated anomalies (20% cardiac)

• 30% are associated with trisomy 13 & 18

• IUGR has been reported in 20% of patients

• 50% have associated anomalies (20% cardiac)

• 30% are associated with trisomy 13 & 18

Fetal Abdomen

• Elevated maternal serum alpha-fetoprotein (70%)• Elevated maternal serum alpha-fetoprotein (70%)


• Omphalocele and cord cyst may co-exist– Whartons jelly cyst – mucoid degeneration of Wharton Jelly

– Allantoic cyst – always near insertion site

– Omphalomesenteric duct cyst – associated with intraabdominal

• Omphalocele and cord cyst may co-exist– Whartons jelly cyst – mucoid degeneration of Wharton Jelly

– Allantoic cyst – always near insertion site

– Omphalomesenteric duct cyst – associated with intraabdominal

Fetal AbdomenJane J.K. Burns, RDMS

mesenteric cystsmesenteric cysts

Diagnostic ChallengeDiagnostic Challenge

Separate from but contiguous with the bladder

Fetal Abdomen

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Patent Urachus With Allantoic CystPatent Urachus With Allantoic Cyst

Urachus is an embryological remnant of the allantois which runs from the apex of the bladder

through the umbilical ring to terminate in the proximal umbilical cord

Fetal Abdomen

Umbilical Cord

Allantoic Stalk

Yolk Stalk

Cloaca

A Ruptured OmphaloceleCan Resemble Gastroschisis

A Ruptured OmphaloceleCan Resemble Gastroschisis

Fetal Abdomen

Omphalocele @11 Weeks ?Omphalocele @11 Weeks ?

Fetal Abdomen

Potential PitfallPotential Pitfall

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Normal Midgut HerniationNormal Midgut Herniation

• Fetal bowel normally herniates into the base of the umbilical cord at approx. the 7-8 weeks MA

• Detected sonographically from 9 11 wks

• Fetal bowel normally herniates into the base of the umbilical cord at approx. the 7-8 weeks MA

• Detected sonographically from 9 11 wks

Fetal Abdomen

• Detected sonographically from 9-11 wks

• Should not be visible by 12 week

• Detected sonographically from 9-11 wks

• Should not be visible by 12 week

“Possible Anomaly”CRL > 44mm with persistent herniation

Maximum dimension of abdominal mass > 7mm

Normal Midgut HerniationNormal Midgut Herniation

• This appearance should not be mistaken for a ventral wall defect

• This appearance should not be mistaken for a ventral wall defect

Fetal Abdomen

Midgut (umbilical) herniation beyond the 12th week of gestation has to be considered pathological

Fetal Abdomen

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GastroschisisGastroschisis

Fetal Abdomen

Small defect to right of cord insertionNo membrane over bowel


• Incidence is 1 in 3000 births– Varies considerably with

maternal age

– Strong association reported among younger patients

• Incidence is 1 in 3000 births– Varies considerably with

maternal age

– Strong association reported among younger patients

Fetal Abdomen

• Less likely for organ herniation

• Variable amounts of bowel herniated

• Bowel floats within amniotic fluid

• Less likely for organ herniation

• Variable amounts of bowel herniated

• Bowel floats within amniotic fluid


• Hepatic herniation is less frequent with gastroschisis than with omphaloceles

• Hepatic herniation is less frequent with gastroschisis than with omphaloceles

Fetal Abdomen

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• Small defect (2-4cm)• Small defect (2-4cm)

Fetal Abdomen


• Associated anomalies in about < 10% of fetuses

• IUGR in up to 50%

• No chromosomal abnormalities

• Elevated maternal serum alpha fetoprotein (70%)

• Associated anomalies in about < 10% of fetuses

• IUGR in up to 50%

• No chromosomal abnormalities

• Elevated maternal serum alpha fetoprotein (70%)

Fetal Abdomen

• Elevated maternal serum alpha-fetoprotein (70%)• Elevated maternal serum alpha-fetoprotein (70%)


• Oligohydramnios – More common than polyhydramnios

– Suggest fetal distress

• Oligohydramnios – More common than polyhydramnios

– Suggest fetal distress

Fetal Abdomen

• Polyhydramnios– Suggest bowel obstruction or atresia

• Polyhydramnios– Suggest bowel obstruction or atresia

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• Marked bowel dilatation, which may be either external or internal to the abdominal cavity, suggests bowel obstruction and/or ischemia

• Marked bowel dilatation, which may be either external or internal to the abdominal cavity, suggests bowel obstruction and/or ischemia

Fetal Abdomen


• Bowel can twist and cut off blood supply• Bowel can twist and cut off blood supply

Fetal Abdomen


Fetal Abdomen

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Fetal Abdomen


Fetal Abdomen

Ectopic Cordis“Large omphalocele coming all the way to heart”

Ectopic Cordis“Large omphalocele coming all the way to heart”

• Rare malformation

• Protrusion of heart through chest wall

• Association - Pentalogy of Cantrell

• Rare malformation

• Protrusion of heart through chest wall

• Association - Pentalogy of Cantrell

Fetal Abdomen

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Pentalogy of CantrellPentalogy of Cantrell

A term used to describe the association of 5 anomalies:

1. Midline supraumbilical abdominal defect

2. Defect of the lower sternum

3 Defect of the diaphragmatic pericardium

A term used to describe the association of 5 anomalies:

1. Midline supraumbilical abdominal defect

2. Defect of the lower sternum

3 Defect of the diaphragmatic pericardium

Fetal Abdomen

3. Defect of the diaphragmatic pericardium

4. Anterior diaphragmatic hernia

5. Intracardiac abnormalities

3. Defect of the diaphragmatic pericardium

4. Anterior diaphragmatic hernia

5. Intracardiac abnormalities

Pentalogy of Cantrell – US FindingsPentalogy of Cantrell – US Findings

• Midline anterior wall defect usually upper abdomen

• Ectopic heart• Pericardial or pleural effusion

• Midline anterior wall defect usually upper abdomen

• Ectopic heart• Pericardial or pleural effusion

Fetal Abdomen

• Craniofacial anomalies• Ascites• Two vessel cord

• Craniofacial anomalies• Ascites• Two vessel cord

Limb-Body Wall ComplexLimb-Body Wall Complex

• Also known as “body stalk” anomaly

• Failure of ventral abdominal wall to close– Often left sided

• Also known as “body stalk” anomaly

• Failure of ventral abdominal wall to close– Often left sided


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• Abdominal organs lie in a sac outside the abdominal cavity

• Short or absent umbilical cord

• Fetus lies directly on placenta*

• Universally fatal

• Abdominal organs lie in a sac outside the abdominal cavity

• Short or absent umbilical cord

• Fetus lies directly on placenta*

• Universally fatal

Fetal Abdomen


• Amniotic bands attached broadly to the fetus & placenta

• Large thoraco-abdominal wall defect – no covering membrane

• Amniotic bands attached broadly to the fetus & placenta

• Large thoraco-abdominal wall defect – no covering membrane


no covering membrane

• Distorted body axis

no covering membrane

• Distorted body axis


• Severe scoliosis – prominent feature

• Limb defects common

• Complex array of multiple malformations

• Severe scoliosis – prominent feature

• Limb defects common

• Complex array of multiple malformations

Fetal Abdomen

– Craniofacial & Internal organ anomalies– Craniofacial & Internal organ anomalies

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Bladder & Cloacal ExstrophyBladder & Cloacal Exstrophy

• Failure of closure of lower abdominal wall resulting in exposed bladder

• Omphalocele• Absent bladder

• Failure of closure of lower abdominal wall resulting in exposed bladder

• Omphalocele• Absent bladder

Fetal Abdomen

• Imperforate anus• Spinal abnormalities• Malformation of the

genitalia• Single umbilical artery

• Imperforate anus• Spinal abnormalities• Malformation of the

genitalia• Single umbilical artery

Bladder ExstrophyBladder Exstrophy

• 2o to abnormal development of the cloacal membrane

• Incidence is 1:30,000 births

• Eversion & exteriorization of the pelvic viscera on the

• 2o to abnormal development of the cloacal membrane

• Incidence is 1:30,000 births

• Eversion & exteriorization of the pelvic viscera on the

Fetal Abdomen

the pelvic viscera on the abdominal surface– Inferiorly displaced umbilicus

– Widely separared pubic bones

the pelvic viscera on the abdominal surface– Inferiorly displaced umbilicus

– Widely separared pubic bones

Reports of T21 & 13

Bladder Exstrophy – US FindingsBladder Exstrophy – US Findings

• Non-visible bladder• Normal kidneys• Normal amniotic fluid

volume

• Non-visible bladder• Normal kidneys• Normal amniotic fluid

volume

Fetal Abdomen

• Low CI• Bulging mass

protruding from the lower abdominal wall

• Small penis • Splayed iliac bones

• Low CI• Bulging mass

protruding from the lower abdominal wall

• Small penis • Splayed iliac bones

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Cloacal ExstrophyCloacal ExstrophyOmphalocele & bladder extrophy with prolapsed ileum between the two bladder halves

Fetal Abdomen

Ventral Wall DefectsRelation to UmbilicusVentral Wall DefectsRelation to Umbilicus

• Above umbilicus– Consider pentalogy of cantrell

• At umbilicusC id hi i h l l

• Above umbilicus– Consider pentalogy of cantrell

• At umbilicusC id hi i h l l

Fetal Abdomen

– Consider gastroschisis or omphalocele

• Below umbilicus– Consider exstrophy of bladder or cloaca

• Difficult to tell because of size– Consider body stalk anomaly

– Consider gastroschisis or omphalocele

• Below umbilicus– Consider exstrophy of bladder or cloaca

• Difficult to tell because of size– Consider body stalk anomaly

Normal Appearance of BowelNormal Appearance of Bowel

• Amniotic fluid is swallowed & as it gets to the small bowel it mixes with bowel mucopolysaccharide

• Moves to the large bowel – water is resorbed, leaving meconium

• Amniotic fluid is swallowed & as it gets to the small bowel it mixes with bowel mucopolysaccharide

• Moves to the large bowel – water is resorbed, leaving meconium

Fetal Abdomen

• Meconium is expelled at birth

• If there is obstruction or if meconium is abnormally thick that wouldn’t pass it causes obstruction in the bowel – meconium ileus

• Meconium is expelled at birth

• If there is obstruction or if meconium is abnormally thick that wouldn’t pass it causes obstruction in the bowel – meconium ileus

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Normal Appearance of BowelNormal Appearance of Bowel

• Meconium– Variable in echogenicity (hypo to hyperechoic), can be

seen throughout the later part of pregnancy, particularly in late 3rd trimester

• Meconium– Variable in echogenicity (hypo to hyperechoic), can be

seen throughout the later part of pregnancy, particularly in late 3rd trimester

Fetal Abdomen

Hyperechoic BowelHyperechoic BowelWhat DoesWhat Does

Fetal Abdomen

What Does

That Mean?

What Does

That Mean?

Hyperechoic BowelHyperechoic Bowel

• Increased echogenicity of the mesentery and small bowel walls

• Increased echogenicity of the mesentery and small bowel walls

Fetal Abdomen

The bowel itself is not echogenic

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Hyperechoic BowelHyperechoic Bowel

• Often normal variant– Related to higher

frequency transducers and to images with greater contrast

• Often normal variant– Related to higher

frequency transducers and to images with greater contrast

Fetal Abdomen

greater contrastgreater contrast

Fetal Abdomen

Echogenic Fetal BowelEchogenic Fetal Bowel

• Abnormal if– > 4 cm in size

– May have mass effect

Homogeneo s or heterogeneo s

• Abnormal if– > 4 cm in size

– May have mass effect

Homogeneo s or heterogeneo s

Fetal Abdomen

– Homogeneous or heterogeneous

– Brightness > bone (femur, spine, iliacs)

– Homogeneous or heterogeneous

– Brightness > bone (femur, spine, iliacs)

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Echogenic Fetal BowelEchogenic Fetal Bowel

• Seen in association with:– Cystic fibrosis, trisomy 21, cytomegalovirus

(CMV), parvo virus (5th disease), GI obstruction and IUGR

• Seen in association with:– Cystic fibrosis, trisomy 21, cytomegalovirus

(CMV), parvo virus (5th disease), GI obstruction and IUGR

Fetal Abdomen

Echogenic BowelEchogenic Bowel

• Swallowed blood (intra-amniotic hemorrhage)• Swallowed blood (intra-amniotic hemorrhage)

Fetal Abdomen

4 days post-amniocentesis4 days post-amniocentesis

Meconium PeritonitisMeconium Peritonitis

• Leaking of bowel contents leading to an intense peritoneal reaction

• Leaking of bowel contents leading to an intense peritoneal reaction

Fetal Abdomen

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• 50% have underlying bowel pathology• 50% have underlying bowel pathology

Fetal Abdomen


• Calcifications 85%– Usually punctate, linear or clumped foci


Fetal Abdomen



• Ascities 54%U ll l



Fetal Abdomen

– Usually complex– Usually complex

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Fetal Abdomen

– Usually complex

• Bowel dilatations 27%

– Usually complex







Fetal Abdomen

– Usually complex


• Pseudocysts 14%

• Polyhydramnios 65%

– Usually complex


• Pseudocysts 14%

• Polyhydramnios 65%


• Calcifications can extend to thorax• Calcifications can extend to thorax

Fetal Abdomen

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• Calcifications can extend to scrotal sac• Calcifications can extend to scrotal sac

Fetal Abdomen

Abdominal CalcificationsAbdominal Calcifications

• Infections: herpes, toxoplasmosis, cytomegalovirus

• Tumors: teratoma, hepatoblastoma, neuroblastoma

• Peritonitis: meconium leak

• Infarcted bowel

• Infections: herpes, toxoplasmosis, cytomegalovirus

• Tumors: teratoma, hepatoblastoma, neuroblastoma

• Peritonitis: meconium leak

• Infarcted bowel

Fetal Abdomen

• Infarcted bowel

• Gallstones

• Idiopathic

• Infarcted bowel

• Gallstones

• Idiopathic

Small & Large

Fetal Abdomen

Bowel ObstructionObstructions below the duodenum are even harder to diagnose

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Small Bowel ObstructionSmall Bowel Obstruction

• Jejunal & ileal obstruction is more common than duodenal obstruction!– Vascular injury

• Jejunal & ileal obstruction is more common than duodenal obstruction!– Vascular injury

Fetal Abdomen

• Small bowel loops can be seen specially in 3rd

trimester• Small bowel loops can be seen specially in 3rd

trimester


• They peristalsis and change in configuration

• Do not persist, and should not be >15 mm in length and 7 mm in diameter

• They peristalsis and change in configuration

• Do not persist, and should not be >15 mm in length and 7 mm in diameter

Fetal Abdomen

7 mm in diameter• Can rarely present as cyst

like mass• Polyhydramnios

– Timing & severity dependent on site of atresia

7 mm in diameter• Can rarely present as cyst

like mass• Polyhydramnios

– Timing & severity dependent on site of atresia

Small bowels are centrally locatedSmall bowels are centrally located


Causes:

• Intestinal atresia– Related to an in utero vascular accident

Causes:

• Intestinal atresia– Related to an in utero vascular accident

Fetal Abdomen

• Stenosis

• Volvulus

• Meconium ileus– In fetuses with cystic fibrosis

• Stenosis

• Volvulus

• Meconium ileus– In fetuses with cystic fibrosis

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PitfallsPitfalls

• Different processes can be mistaken for dilated small bowel– Cysts in an enlarged multicystic displastic kidney

Dilated tortuous ureter

• Different processes can be mistaken for dilated small bowel– Cysts in an enlarged multicystic displastic kidney

Dilated tortuous ureter

Fetal Abdomen

– Dilated tortuous ureter – Dilated tortuous ureter

Large Bowel ObstructionLarge Bowel Obstruction

• Normal large bowel < 20 mm diameter

• Rare - It occurs at the anal-rectal region

• Additional structural &

• Normal large bowel < 20 mm diameter

• Rare - It occurs at the anal-rectal region

• Additional structural &

Fetal Abdomen

chromosomal anomalies are very common (75%)– VACTERL & caudal regression

syndrome

Causes:• Atresia• Stenosis

chromosomal anomalies are very common (75%)– VACTERL & caudal regression

syndrome

Causes:• Atresia• Stenosis

Solid Abdominal MassesSolid Abdominal MassesMesoblastic nephroma Neuroblastoma Hepatoblastoma

Fetal AbdomenSubdiaphragmatic extralobar

pulmonary sequestration

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Fetal Abdomen

Abdominal CystsDifferential Diagnosis

Abdominal CystsDifferential Diagnosis

• RUQ– Hepatic/choledochal cyst

• LUQ– Splenic cyst

• PosteriorRenal cyst hydronephrosis

• RUQ– Hepatic/choledochal cyst

• LUQ– Splenic cyst

• PosteriorRenal cyst hydronephrosis

Fetal Abdomen

– Renal cyst, hydronephrosis

• Anterior/mid-abdomen– Mesenteric cyst, umbilical vein varix

• Lower abdomen– Ovarian cyst (but may migrate to mid-abdomen)– Ureterocele– Urachal cyst– Hydrometrocolpos

– Renal cyst, hydronephrosis

• Anterior/mid-abdomen– Mesenteric cyst, umbilical vein varix

• Lower abdomen– Ovarian cyst (but may migrate to mid-abdomen)– Ureterocele– Urachal cyst– Hydrometrocolpos


Fetal Abdomen

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Fetal Abdomen

There is Flow! Is it venous or arterial?There is Flow! Is it venous or arterial?

Fetal Abdomen

Umbilical Vein VarixUmbilical Vein Varix

• Focal dilatation of umbilical vein

• Usually intraabdominal but extrahepatic may occur in association with persistent right umbilical vein

• Focal dilatation of umbilical vein

• Usually intraabdominal but extrahepatic may occur in association with persistent right umbilical vein

Fetal Abdomen

umbilical vein

• It may also occur in free floating loops of cord

• Umbilical vein varix of intra-amniotic segment is rarer than intra-abdominal

umbilical vein

• It may also occur in free floating loops of cord

• Umbilical vein varix of intra-amniotic segment is rarer than intra-abdominal

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• Focal dilatation of intra-abdominal portion

– Usually near cord insertion

– Abnormal if internal diameter > 9 mm or twice size of intrahepatic portion of vein

Normal size at week 20 is 3 4 mm with linear increase up

• Focal dilatation of intra-abdominal portion

– Usually near cord insertion

– Abnormal if internal diameter > 9 mm or twice size of intrahepatic portion of vein

Normal size at week 20 is 3 4 mm with linear increase up

Fetal Abdomen

– Normal size at week 20 is 3-4 mm with linear increase up to 8 mm at term

– Normal size at week 20 is 3-4 mm with linear increase up to 8 mm at term


Fetal Abdomen


• Can be associated with:– Chromosome abnl (T-21, 18, 9)

– Congenital malformations– Decreased growth

H d

• Can be associated with:– Chromosome abnl (T-21, 18, 9)

– Congenital malformations– Decreased growth

H d

Fetal Abdomen

– Hydrops– Thrombosis

• May be first manifestation of elevated venous pressure therefore may signify increased risk of cardiac decompensation

• As isolated finding: normal outcome

– Hydrops– Thrombosis

• May be first manifestation of elevated venous pressure therefore may signify increased risk of cardiac decompensation

• As isolated finding: normal outcome

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Choledochal CystCholedochal Cyst

• Cystic dilatation of the CBD

• Separate from gallbladder

• No communication with stomach

• Cystic dilatation of the CBD

• Separate from gallbladder

• No communication with stomach

Fetal Abdomen

Abdominal CystsAbdominal Cysts

Fetal Abdomen

Abdominal CystsAbdominal Cysts

• Lower abdomen – Female: think ovarian: may migrate/auto-amputate

• Torsion in ~ 40 % if > 5 cm

• Lower abdomen – Female: think ovarian: may migrate/auto-amputate

• Torsion in ~ 40 % if > 5 cm

Fetal Abdomen

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Thank YouThank You

Fetal Abdomen

Thank YouThank You

Fetal abdomen

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