chapter 62 fetal anterior abdominal wall Flashcards
abdominal wall defects occur during the ____ trimester
first trimester
the midgut usually returns into the abdominal cavity by week
11-12
most common types of abdominal wall defects
- gastroschisis
- omphalocele
- umbilical hernia
this develops when there is a midline defect of the abdominal muscles, fascia, and skin that results in herniation of intraabdominal structures into the base of the umbilical cord
omphalocele
omphalocele: AFP levels:
normal or slightly elevated
two types of omphalocele:
- contains liver in the sac
2. contains bowel w/o liver
this type of omphalocele has a higher risk for chromosomal abnormalities
bowel omphalocele
this omphalocele affects the abdominal wall muscles, fascia, and skin
liver omphalocele
fetal mortality with isolated omphalocele
10%
fetal mortality increases to ____% when more than 1 abnormality exists
80%
bowel omphaloceles appear ____
echogenic
bowel omphaloceles must be distinguished from umbilical hernia, this is done by:
checking the cord insertion: normal cord insert suggests umbilical hernia
assosciated anomalies with omphalocele:
- cardiac
- gastrointestinal
- neural tube defects
- genitourinary tract
Periumbilical defect, opening in the layers of the abdominal wall with herniation of bowel.
gastroschisis
gastroschisis is almost always located:
to the right of the umbilicus
gastroschisis infrequently involves:
- stomach
- genitourinary organs
- rarely involves liver
theoretically, gastroschisis is a consequence of
atrophy of the right umbilical vein or distruption of the omphalomesentric artery
gastroschisis size:
2-4cm
umbilical cord insertion in fetuses with gastroschisis:
normal
_____ is always found in the herniation of gastroschisis
small bowel
AFP levels with gastroschisis
highly elevated
why are AFP levels elevated in gastroschisis
because it is an open defect–exposed bowel
gastroschisis is more common in
males
Gastroschisis is sonographically detectable after ___ weeks gestation
12 weeks
notably dilated bowel may suggest :
infarction or bowel atresia
rupture of the amnion which leads to the entrapment/entanglement of fetal parts:
amniotic band syndrome
How do you differentiate an omphalocele from gastroschisis
- presence of membrane(gastro doesn’t have one)
- look at cord(gastroschisis will have a normal cord)
- omphalocele often occurs with chromosomal anomalies
Rare group of disorders that involves macroglossia, omphalocele, visceromegaly(enlarged abdominal organs)
Beckwith-Weidmann syndrome
defect in the lower abdominal wall & anterior wall of the bladder
bladder exstrophy
protrusion of bladder through the abdominal wall defect
bladder exstrophy
bladder exstrophy is accompanied with
omphalocele inguinal hernia chrytorchidism -anal problems genital malformations
in bladder exstrophy, the urinary bladder is ___
not visible
soft tissue mass that represents the exposed bladder mucosa seen on the surface of the lower abdominal wall:
bladder exstrophy
occurs in early development with involvement of primitive gut and persistent cloaca
cloacal exstrophy
extrophy of badder in which two hemibladders are separated by intestinal mucosa
cloacal exstrophy
cloacal exstrophy involves
- lower abdominal wall defect below the cord insertion including extrophy of bladder and protrusion of intestines
- lower limb abnormalities
- spinal defects
- anal atresia
primary finding in cloacal exstrophy
anterior abdominal wall defect
cloacal extrophy may also have abnormally ____ cord insert
low
Rare, association of all 5 defects:
- cleft in distal sternum
- Diphragmatic defect
- Midline anterior ventral defect
- Defect of apical pericardium with communication into peritoneum
- internal cardiac defect
Pentalogy of Cantrell
usual primary finding in Pentalogy of Cantrell
high or superumbilical omphalocele
Exposed heart presents outside chest through a cleft sternum:
ectopia cordis
ectopia cordis is associated with these anomalies;
- omphalocele
- cardiovascular malformations
- craniofacial defects
occurs with fusion of amnion and chorion
limb-body-wall complex
limb-body-wall defects: more commonly affects what side:
affects the left side 3x more than the right
associated with
- large cranial defects
- facial clefting
- body wall complex defects involving throrax and abdomen
- limb defects
- scoliosis
- various internal malformations
limb-body-wall complex
with limb-body-wall complex, the umbilical cord is:
short and adherent to placental membranes or absent
limb-body-wall complex sonographically:
- large defects
- involve abdomen and thorax
- bizarre appearing mass entangled with membranes
