chapter 63 fetal abdomen

Question 1

fetal organs are well formed by the ___

Answer 1

2nd trimester

Question 2

forms when intestines return normally to abdominal cavity & herniate either prenatally or postnatally through an inadequately closed umbilicus

Answer 2

umbilical hernia

Question 3

how does a hernia differ from omphalocele?

Answer 3

hernia is covered by subcutaneous tissue & skin, omphalocele is only covered by subcutaneous tissue.

Question 4

most common malformation of the midgut

Answer 4

meckel’s diverticulum

Question 5

usually a small finger-like sac about 5cm long, projects from the border of the ileum

Answer 5

meckel’s diverticulum

Question 6

remnant of the proximal part of the yolk sac that fails to degenerate and disappear during the early fetal period

Answer 6

meckel’s diverticulum

Question 7

most fetuses older than ____ should have fluid in their stomach

Answer 7

16 weeks

Question 8

if fluid is not seen in the stomach, the stomach should be reevaluated in ______

Answer 8

20-30 minutes

Question 9

if an echogenic mass is seen in the fetal stomach, in a patient with clinical or sonographic evidence of an abruption, this could possibly be:

Answer 9

a hematoma associated with intraamniotic hemorrhage

Question 10

normal esophagus can be visualized in the thorax during the :

Answer 10

2nd and 3rd trimesters

Question 11

visualization of the umbilical cord site must be made to rule out:

Answer 11

• omphalocele
• gastroschisis
• hernia
• mass formation

Question 12

after birth the umbilical vein collapses and forms the _____

Answer 12

ligamentum teres

Question 13

because the fetus is capable of swallowing sufficient amounts of amniotic fluid in the 1st trimester, the stomach may be visualized by approximately ____

Answer 13

11-weeks

Question 14

meconium begins to accumulate in the distal part of the small intestine after ____

Answer 14

15-16 weeks

Question 15

distinction of large bowel from small bowel is possible after ____

Answer 15

20 weeks

Question 16

small bowel is slightly ______ compared to the liver

Answer 16

hyperechoic

Question 17

after _____, normal peristalsis is increasingly observed

Answer 17

27 weeks

Question 18

colon can be identified at the:

Answer 18

end of the 2nd trimester

Question 19

colon appears:

Answer 19

long, tubular, hypoechoic structure with well-defined walls

Question 20

colon does/doesn’t have peristalsis like small bowel:

Answer 20

doesn’t

Question 21

after 14 weeks, meconium appears ____ compared to fetal liver

Answer 21

hypoechoic

Question 22

Meconium ____ in echogenicity closer to term

Answer 22

increases

Question 23

liver ____ in fetuses with Rh-isoimmunization

Answer 23

enlarges due to increased production of blood(hematopoiesis)

Question 24

sonographically, most liver tumors appear

Answer 24

solid and hypoechoic

Question 25

about ___% of benign and malignant liver tumors are calcified

Answer 25

5%

Question 26

reversal of thoracic and abdominal organs

Answer 26

situs inversus

Question 27

prognosis in patients with total situs inversus

Answer 27

good/normal

Question 28

prognosis of patients with partial situs inversus

Answer 28

high mortality rate

Question 29

partial situs inversus is diveded into:

Answer 29

Aspenia Polysplenia

Question 30

partial situs inversus: Asplenia:

Answer 30

- absent spleen - stomach and galbladder are more midline - liver is more central - abnormal positioning of aorta/IVC on same side

Question 31

partial situs inversus: Asplenia mortality rate:

Answer 31

95%

Question 32

partial situs inversus: Polysplenia:

Answer 32

- absent gallbladder - interuption of IVC - more than one spleen, located along greater curvature of stomach(right side)

Question 33

partial situs inversus: Polysplenia mortality rate:

Answer 33

80%

Question 34

cardiac malformations occur ____% in asplenia

Answer 34

99%

Question 35

cardiac malformations occur ____% in polysplenia

Answer 35

90%

Question 36

true ascites is seen within the ____ and in the spaces between _____

Answer 36

peritoneal recesses small bowel loops

Question 37

true ascites outlines the ___

Answer 37

falciform ligament

Question 38

sonolucent band near the fetal anterior abdominal wall, is commonly seen in routine OB exams over 18 weeks

Answer 38

psuedoascites

Question 39

pseudoascites never outlines the ____

Answer 39

falciform ligament

Question 40

agenesis of the gallbladder occurs in approximately ___% of patients with biliary atresisa

Answer 40

20%

Question 41

spleen may _____ in fetuses with Rh-isoimmunization

Answer 41

enlarge

Question 42

GI malformations are important to detect before birth to help prevent:

Answer 42

- dehydration - bowel necrosis - respiratory difficulties

Question 43

develops when portion of bowel grows, infarcts, and then doesn't develop completely(GI)

Answer 43

atresia

Question 44

bowel loops above the atresia ____

Answer 44

enlarge

Question 45

bowel loops below the atresia ____

Answer 45

narrow

Question 46

atresia results in

Answer 46

hydramnios

Question 47

congenital blockage of the espophagus

Answer 47

esophageal atresia

Question 48

results from faulty separation of the foregut into its respiratory & digestive components

Answer 48

esophageal atresia

Question 49

esophageal atresia most commonly occurs with ____

Answer 49

fistula/tracheoesophageal fistula

Question 50

combination of ____ and _____ over repeated exams suggest esophageal atresia

Answer 50

polyhydramnios and absent stomach

Question 51

most common anomaly seen with esophageal atresia:

Answer 51

anorectal atresia

Question 52

blockage of duodenal lumen by a membrane:

Answer 52

duodenal atresia

Question 53

amniotic fluid fails to move past the obstruction in the duodenum and backs up into the duodenum and stomach. This creates the ____ sign

Answer 53

double-bubble sign

Question 54

duodenal atresia often exists with _____ pancreas

Answer 54

annular pancreas

Question 55

which trisomy is associated with duodenal atresia?

Answer 55

trisomy 21

Question 56

AFP is _____ due to faulty swallowing in duodenal atresia

Answer 56

elevated

Question 57

double-bubble sign most commonly results from:

Answer 57

duodenal atresia

Question 58

atresia of the ____ or _____, or both, is slightly more common than duodenal atresia

Answer 58

jejunum or ileum

Question 59

atresia of the jejunum/ileum is most often caused by

Answer 59

vascular accident

Question 60

blockage of the jejunum and ileum appears as:

Answer 60

multiple cystic structures proximal to the cite of atresia

Question 61

the more distal the obstruction(bowel) the ___ severe the hydramnios

Answer 61

less

Question 62

the dilated bowel loops can be isolated, or associated with other anomalies:

Answer 62

- ascites | - meconium peritonitis

Question 63

this is the earliest manifestation of cystic fibrosis

Answer 63

meconium ileus

Question 64

presence of thick overproduced meconium in the distal ileum

Answer 64

meconium ileus

Question 65

meconium ileus sonographically appears:

Answer 65

tiny echogenic reflections in the peristalsic small bowel

Question 66

other conditions, besides meconium ileus, that are associated with echogenic bowel

Answer 66

- cytomegalovirus | - trisomy 21

Question 67

complex disorder of the bowel and genitourinary tract. imperforate anus is found with this

Answer 67

anorectal atresia

Question 68

occurs when a membrane covers the anus, preventing expulsion of meconium

Answer 68

imperforate anus--anorectal atresia

Question 69

hirschsprung's disease AKA:

Answer 69

megacolon

Question 70

abnormal innervation of large intestines

Answer 70

hirschsprung's disease/megacolon

Question 71

sonographic appearance of hirschsprung's disease(megacolon)

Answer 71

- dilated bowel loops | - difficult to diagnose prenatally

Question 72

arises when fetus has sterile chemical peritonitis secondary to in-utero bowel perforation

Answer 72

Meconium peritonitus

Question 73

sonographic appearance of meconium peritonitis:

Answer 73

- calcifications on peritoneal surfaces or in scrotum - may cause psuedocyts - ascites fluid may be echogenic

Question 74

with hyperechoic bowel, bowel is compared to the brightness of ____

Answer 74

bone

Question 75

hyperechoic bowel is usually seen in the ____ trimester

Answer 75

2nd trimester

Question 76

true ascites is always ___

Answer 76

abnormal

Question 77

fluid collects between 2 leaves of unfused omentum, results in cystic appearance in abdomen:

Answer 77

ascites

Question 78

ascites prognosis with non-immune hydrops:

Answer 78

poor

Question 79

cystic masses of the abdomen can result in compression of other organs, creating:

Answer 79

- hydronephrosis - hydroureter - fetal hydrops