study guide test 2 Flashcards
Which anomaly refers to a fetus with a significantly narrow chest diameter?
asphyxiating thoracic dystrophy
What is the most important determinate for fetal viability?
pulmonary development
Sonographic evaluation of normal thorax: What should it include?
examined in both trans and coronal or parasagittal planes
thoracic cavity is symmetrically bell-shaped: with the ribs forming the lateral margins, the clavicles forming the upper margins, and the diaphragm forming the lower margins
lungs serve as the lateral borders for the heart and lie superior to the diaphragm
Chest circumference measurements are made in trans plane at what level?
four chamber view of the heart
Fetal breathing
most prominent in the 2nd and 3rd trimester
mature fetus spends 1/3 of the time breathing
breathing is present if the fetal chest of abd makes seesaw movements for 20sec
What are the cardiac access degrees?
normal ranges from 22-75 degrees (average 45 degrees)
What abnormalities are associated with pulmonary hypoplasia?
renal agenesis
premature rupture of membranes
posterior urethral valve syndrome
Sonographic findings for CAM:
Type I: single or multiple large cysts 2cm in diameter; good prognosis after resection of affected lung
Type II: multiple small cysts <1cm in diameter, echogenic; high incidence of other congenital anomalies (renal gastrointestinal)
Type III: large, bulky, noncystic lesions producing mediastinal shift; poor prognosis
Ussually 1 lobe is affected; associated with polyhydramnios and anascrea; poor prognosis
Diaphragmatic hernia: anteriomedial
Foramen of Morgagni
What lung cyst is the most common?
bronchogenic cyst
Severity of pulmonary hypoplasia is determined by what?
depends on when pulmonary hypoplasia occurred during pregnancy, its severity, and its duration
What is the supernumerary of the lung called?
pulmonary sequestration
What is the normal sonographic appearance of the fetal chest?
majority of the heart is positioned in the midline and left chest
Apex of the heart should be directed toward the spleen
base of the heart lies horizontal to the diaphragm
What is the appearance of fetal lungs on ultrasound?
homogeneous with moderate echogenicity
If you see pleural fluid, what should you be looking for?
diaphragm?????
Pulmonary Sequestration and its sonographic findings:
it is a supernumerary lobe of the lungs, separated from the normal tracheobronchial tree
findings: echogenic solid mass resembling lung tissue; rarely occurs below diaphragm; associated with hydrops and polyhydramnios, diaphragmatic hernia, gastrointestinal anomalies; normal intra-abdominal anatomy
Where is congenital bronchial atresia most commonly located?
left upper lobe
What is the most common type of diaphragmatic defect?
foramen of Bochdalek
What is the mortality rate at birth for a fetus with a diaphragmatic hernia?
high
What is a diaphragmatic hernia frequently associated with?
cardiac malformations
central nervous system malformations
renal anomalies
vertebral defects
pulmonary hypoplasia
facial clefts
If there is pleural fluid, what could happen?
a shift
What is a rupture of amnion that leads to entanglement or entrapment?
amniotic band syndrome
What is the defect in the lower abdominal wall and lower anterior wall of the bladder?
bladder exstrophy (cloacal exstrophy-rare and more complex)
An anomaly with large cranial, facial, and body wall defects is called?
limb-body wall complex
Which abnormality would have visceration of bowel to the right of the umbilical cord?
gastroschisis
If you have an omphalocele and scoliosis is also present, what should you consider?
limb-body wall complex
If an omphalocele is low, what other anomalies should you consider?
bladder or cloacal exstrophy
anal atresia
spina bifida
What all does Beckwith-Wiedemann Syndrome include?
macroglossia
omphalocele
visceromegaly
Gastroschisis is a consequence of atrophy of what vessel?
right umbilical vein
What will you see with a lower abdominal wall in bladder exstrophy?
omphalocele
inguinal hernia
undescended testes
anal problems
What abdominal wall defects are the most common?
gastroschisis
umbilical hernia
omphalocele
Critical part of the process of closing the umbilical wall:
folding
Normal embryonic herniation of the bowel permits what?
midgut grows faster than the abdominal cavity at this stage because of the increased size of the liver and kidneys
What is omphalocele?
omphalocele with only bowel has a higher risk for chromosomal abnormalities and other anomalies
If you have a 19wk fetus with an elevated MSAFP, and you see herniated, free floating bowel loops, what should you consider?
gastroschisis
What are the 5 defects of Pentalogy of Cantrell?
cleft distal sternum
diaphragmatic defect
midline anterior ventral wall defect
defect of the apical pericardium with communication into the peritoneum
internal cardiac defect
What is gastroschisis?
occurs more frequently in males
located to the right of normal cord insertion
MSAFP levels are significantly elevated
What is the prognosis with gastroschisis?
excellent
What is the most dramatic finding in ectopia cordis?
heart is outside the thoracic cavity
A high or superumbilical omphalocele is usually the primary finding of what condition?
Pentalogy of Cantrell
Limb body wall defects are more common on which side?
left side
What common anomalies coexist with gastroschisis?
coexisting anomalies are rare
Notably dilated, free floating bowel loops; what might this suggest?
Infarction????
Herniation of an omphalocele is covered in a membrane that consists of what?
amnion and peritoneum
Umbilical vein drains:
placenta
body stalk
evolving abdominal wall
Hepatic bud enlarges and the right umbilical vein atrophies during what wk of gest?
7-9wks???
Fetus with partial situs inversus demonstrates what?
thoracic viscera are usually reversed
abdominal viscera may or may not be reversed
Evidence of a double bubble in a fetus with Tri 21. What is this condition?
duodenal atresia
Fetus with dilated loops of echogenic bowel should be evaluated for what?
meconium peritonitis
duodenal atresia
bowel obstruction
Where is the spleen visualized in ultrasound?
trans plane posterior and to the left of the fetal stomach
What causes echogenic areas in the fetal abdomen?
calcified:
peritoneal calcification-meconium peritonitis, hydrometrocolpos
intraluminal meconium calcification-anorectal atresia, small bowel atresia, rarely isolated without bowel obstruction
parenchymal-liver, splenic, ovarian cyst
cholelithiasis-gallbladder
noncalcified:
echogenic meconium
intraabdominal extrathoracic pulmonary sequestration
tumors
adrenal hemorrhage
What is a cystic growth of the common bile duct?
choledochal cyst
Haustral folds can be found in what structure?
colon
A remnant of the prox part of the yolk stalk is called?
Meckel’s diverticulum
Sonographic demonstration of normal esophagus in 2nd and 3rd tri will appear as what?
2 or more parallel echogenic lines (multilayered pattern)
Most common malformation in the midgut is?
Meckel’s diverticulum
How early can you distinguish between large and small bowel?
after 20 menstrual wks
Fetal stomach:
most fetuses older than 14-16wks should have fluid in their stomachs
echogenic debris may be visualized along dependent wall of stomach (vernix, protein, or intraamniotic hemorrhage)
esophageal anomalies are the least common problem for nonvisualization of the stomach
Transposition of the liver, stomach, absence of the gb, multiple spleens, disruption of the IVC; what is this condition?
polysplenia
Sonolucent band identified near the fetal anterior abdominal wall?
pseudoascites
What is the most reliable criteria for dilated bowel loops?
bowel diameter???
Causes for double bubble:
diaphragmatic hernia
annular pancreas
Ladd’s bands
duodenal stenosis
duodenal atresia
prox jejunal atresia
malrotation
What coexisting anomalies are common with esophageal atresia?
anorectal atresia (most common)
vertebral defects
heart defects
renal and limb anomalies
What are the derivatives of the hindgut?
left part of the transverse colon
descending colon
sigmoid colon
rectum
superior portion of anal canal
epithelium of the urinary bladder
most of the urethra
What is the normal diameter of fetal small bowel?
5mm
What is the sonographic appearance for choledochal cyst?
close prox of the cyst to the neck of the gb
ovoid RUQ cyst with an entering bile duct
cyst and gb that enlarge as gest progresses
absence of peristaltic activity in the cyst
Peritoneal calcification at 30wks gest. What is it?
meconium peritonitis
VACTERL is a group of anomalies assc with what anomaly?
anorectal atresia
Fetal liver:
large compared with other intra-abdominal organs
hepatic veins and fissures are formed by end of 1st tri
occupies most of upper abdomen
What is situs inversus?
total-right side heart axis and aorta, transposistion of liver, stomach, and spleen; left side gb
partial-right side stomach; left side liver
Complex disorder of the bowel and genitourinary tract is?
anorectal atresia
