B5-069 GI Embryology Flashcards
(89 cards)
1
Q
buccopharyngeal membrane is the site of future
A
mouth
2
Q
cloacal membrane is the site of the future
A
anus
3
Q
ventral mesentary forms the
A
hepatogastric portion of lesser omentum
4
Q
dorsal mesogastrium forms the
2
A
greater omentum and gastrocolic liagment
5
Q
only the […] has both dorsal and ventral mesentary
A
foregut
mid and hind only have dorsal
6
Q
portion of stomach that grows much larger forming the greater curvature
A
original posterior portion
7
Q
lienal =
A
splenic
8
Q
dorsal mesentary forms the
A
greater omentum
9
Q
ventral mesentary forms the
A
lesser omentum
10
Q
the endodermal lining of the yolk sac becomes the
A
primitive gut
surronded by splanchnic mesoderm
11
Q
2nd most common GI abnormality
A
infantile pyloric stenosis
12
Q
male
3-10 weeks old
projectile, non-bilious vomiting
A
infantile pyloric stenosis
13
Q
“olive” caudal to costal margin near midline
A
infantile pyloric stenosis
14
Q
infants with pyloric stenosis may suffer from […] and […] due to loss of gastric acid
A
dehydration
hypochloremia
15
Q
hypertrophy of pyloric spinchter muscles
A
plyloric stenosis
16
Q
treatment for pyloric stenosis
A
- IV hydration
- oral atropine (relax spinchter)
- surgical intervention
17
Q
suspends gut tube from posterior body wall
A
dorsal mesentary
18
Q
forms the lower portion of septum transversum
A
ventral mesentary
foregut
19
Q
the pancreas, 3rd and 4th portions of the duodenum become […] as gut is rotating
A
retroperitoneal
20
Q
- evolutionarily conserved transcription factors that are used in regional patterning
- used in both mesoderm and endoderm
A
Hox genes
21
Q
hole in back of diaphragm
A
Bochadlek
22
Q
most congenital diaphragmatic hernias occur on which side?
A
left
23
Q
hole in front of diaphragm near the xiphiod process
A
morgagni hole
24
Q
- difficulty breathing
- fast breathing
- fast heart rate
- cyanosis
- abnormal chest development
- abdomen appears caved in
A
CHD
25
CHD is typically diagnosed when in pregnancy?
22-24 weeks
or in 1st trimester screening US
26
liver and gallbladder buds grow into the lower portion of the
septum transversum
27
Bockdalek hernia are [...] and to [...]
back and to the left
| 90% of CDH
28
breath sounds on right, bowel sounds on left side of chest
CDH
29
forms the falciform ligament and lesser omentum
ventral mesentary
30
liver growth causes the lower portion of the septum transversum to
thin
| leaves falciform
31
part of the liver fuses with the developing diaphragm leaving
| 2
bare area of liver
coronary ligament
32
intially, dorsal and ventral [...] form on opposite sides of the end of the foregut tube
pancreatic buds
| ventral migrates around in 5th week
33
thought to arise when single ventral pancreatic bud fails to migrate and fuses to duodenum
or
when two ventral pancreatic buds form and migrate in opposite directions, constricting duodenum
annular pancreas
34
* polyhydramnios in utero
* difficulty feeding after birth
* non bilious vomiting
* starting day 1 for newborns
annular pancreas
35
* associated with maternal polyhydramnios,
* down syndrome,
* esophageal and duodenal atresia,
* imperforate anus,
* Meckel's diverticulum
complete annular pancreas
36
about 1/3 of newborns with annular pancreas have
trisomy of a chromosome
**21, 18 or 13**
37
in adults, this condition is associated with:
* epigastic pain
* pancreatitis
* upper GI bleeding from peptic ulceration
* other GI issues
annular pancreas
38
treatment for annular pancreas
typically requires surgery
| duodenal bypass
39
* early (<24 hours) vomiting that may contain bile
* abdomen not dilated
* maternal polyhydramnios in 50% of cases
duodenal atresia
40
double-bubble sign
duodenal atresia
| gas in stomach and 1st part of duodenum
41
VACTERL association
duodenal atresia
anal atresia
42
duodenal atresia is associated with other congenital abnormalities [...]% of the time
50%
43
VACTERL stands for
Vertebral defect
Anal (and duodenal) atresia
Cardiac defects
Tracheo-esophageal fistula
Renal anomalies
Limb abnormalities
44
annular pancreas and duodenal atresia are hard to distinguish without
imaging
45
why can focal obstruction of the GI tract occur in almost any small lumen?
luminal occlusion by endoderm -> recanalization
| recanalization failure = obstruction
46
recanalization errors can cause
| 5
1. cysts
2. duplications
3. septa formation
4. diverticuli
5. failure to reopen lumen
47
forms primary intestinal loop with the superior mesenteric artery on its axis
midgut
48
from the 6th week to 10th week, the instestines are physiologically
hernia
| occuring at same time as recanalization
49
recanalization occurs during what weeks of development
6-9
50
failure of the gut to return to the peritoneal cavity
omphalocele
51
in an omphalocele, the intestinal loops is covered with [...] which is attached to an enlarged umbilical cord
amnion
52
navel covered with thin layer of amnion
omphalocele
53
* involve herniated small intestine only
* repaired shortly after birth
* may be able to be delivered vaginally
small omphalacele
54
* may involve herniated liver and even spleen
* may require multiple surgeries
* typically delivered via C section
omphalocele
55
* detected by prenatal US
* elevated alpha-fetoprotein levels
| 2
omphalocele
gastroschisis
56
about half of babies with omphaloceles have trisomy of
chromosomes 18 or 21
57
25-45% of babies with omphalocele have other birth defects like
| 4
* heart defects
* neural tube defects
* CDH
* chromosomal abnormalities
58
* maternal age younger than 20 or older than 35
* alcohol/tobacco use while pregnant
* SSRIs
* obesity
| risk factors for
omphalocele
59
failure of body wall closure followed by gut herniation
gastroschisis
60
* typically occurs to the right of umbilicus
* intestines not covered with membrane
gastroschisis
61
defect in anterior abdominal wall through rectus abdominis, just to right of umbilicus
gastroschisis
62
gastroshisis is more frequent in [...] mothers
young, teenage
63
gastroschisis is inherited in an [...] manner
autosomal recessive
| not associated with other congenital defects
64
greatest risk for ischemia of gastroschisis
volvulus
65
congenital anomaly of gut due to remnant of vitelline duct
meckel's diverticulum
66
meckel's diverticulum is a remnant where the vitilline duct was attached to the [...]
ileum
67
rule of 2s for Meckel's
* 2% of population
* 2'' long
* located 2 ft from ileocecal junction
* presents before age 2
* may contain 2 ectopic tissue (stomach/pancreas)
68
* abdominal pain
* blood in stool
* presents before age 2
* twice as frequent in males
Meckel's diverticulum
69
pain mimics appendicitis but that doesn't happen in two year olds
meckel's
70
how is Meckel's diagnosed?
* radioactive technetium-99 injection and pertechetate scan
* colonoscopy
71
caused by failure of neural crest cell to migrate around developing intestines
hirschsprung disease
72
failure of RET gene
hirschsprung disease
73
results in non-motile portion of bowel due to lack of ENS
hirschsprung disease
74
suspected if meconium is not passed within 48 hours of birth
hirschsprung disease
75
* abdominal distension
* constipation
* diagnosed prior to first birthday
hirschsprung disease
76
hirschsprung disease is associated with trisomy
21
77
often discovered when unable to obtain rectal temp
imperforate anus
78
why does imaging follow the discovery of anal atresia?
1. to plan surgical correction
2. **to look for other congenital defects**
79
typically [...] VACTERL defects are present in affected individuals
3
80
imperforate anus is associated with trisomy
18/21
81
the part that prolapses into the other is called the [...] and the part that receives it is called the [...]
1. intussusceptum
2. intussuscipiens
82
* below age of 5
* sudden pain that comes and goes
* vomiting
* stool mixed with blood
* cramping abdominal pain
* may palpate "sausage mass"
intussusception
83
bull's eye or target appearance on US
intussusception
84
treatment intussusception
barium or air enema
laparotomy
surgery
85
most common location of intussusception
ileocecal junction
86
adults who have their spleen removed are at a 10-20x higher risk of death due to
sepsis
87
most babies born without a spleen [...] within the first few months of life
die
| due to infection
88
asplenia or polysplenia are often associated with
other congenital defects
89
a single accessory spleen or lobulated spleen is usually
asymptomatic
