3/20 Disease of Abd Wall - Corbett

Question 1

gastroscisis

Answer 1

abnormal folding of body wall → ventral vody wall defect (full-thickness)

due to failure of mesoderm forming in body wall

rupture of amnion around umbilical ring

Question 2

omphalocele

Answer 2

extraembryonic gut (extruded through umbilicus for devpt/rotation) fails to return

peritoneum and amnion still cover the extruded bowel!

why worse than gastroschisis? worse associated anomalies!

• high risk of aneuploidy
• other structural anomalies (VACTERL)

Question 3

gastroschisis vs omphalocele

Answer 3

Question 4

Meckel’s diverticulum

• Rule of 2s

Answer 4

incomplete obliteration of vitelline duct

common pres: bleeding

Rule of 2s:

2” long, within 2ft ileocecal valve, 2% of pop, 2yrs of age, 2 epi types (gastric, pancreatic)

Question 5

structural components of mature diaphragm

Answer 5

1. septum transversum
2. pleuroperitoneal membranes
3. mesoderm of body wall
4. esoph mesoderm

Question 6

diaphragmatic hernias

Answer 6

1. Bochdalek hernia (most common, 95%) → posterolateral portion of diaphragm
2. Morgnani hernia/other anterior
3. central hernia

see herniation of viscera into the chest

• hypoplastic lung on affected side with hypoxemia and pulmo HTN
• pushes heart over

Question 7

sliding hiatus hernia

paraesophageal hernia

Answer 7

Type 1 hiatus hernia

hiatus widens, stomach and GE jx slide into chest

• no hernia sac
• structures remain in post mediastinum

50% of pt with GERD → type I hiatus hernia

Type 2 hiatus hernia

GE jx still at/below diaphragm

• fundus slides up past diaphragm
• can lead to gastric volvulus!

Question 8

abdominal wall hernias

Answer 8

1. indirect inguinal

2. direct inguinal

3. femoral

4. umbilical

inguinal type are most common

more common in males → susceptibility due to descent of testes

Question 9

descent of testes

Answer 9

Question 10

distiniguishing between indirect vs direct inguinal hernia

Answer 10

position relative to inferior epigastric vessels

• LATERAL to vessels? indirect
• MEDIAL to vessels? direct
  
  • exit abd via hesselbach’s triangle
  • reflext weakness in transversalis fascia

Question 11

femoral hernias

Answer 11

located INFERIOR to inguinal ligament, MEDIAL to femoral vein

mnemonic: NAVL (nerve, artery, vein, lymphatic - lateral to medial)

Question 12

ventral mesentary derivatives

dorsal mesentary derivatives

Answer 12

VENTRAL

1. hepatic ligaments

• falciform ligament
  
  • coronary
  • triangular

2. lesser omentum

• hepatogastric
• hepatoduodenal

DORSAL

1. greater omentum

• gastrocolic
• gastrosplenic
• splenorenal
• gastrophrenic
• mesentery of small int
• mesocolon

Question 13

foramen of Winslow

gastroduodenal ligament - Pringle maneuver

Answer 13

Question 14

intestinal malrotations

Answer 14

bowel twists on itself leading to eventual ischemia/necrosis of bowel as blood supply is compromised

“apple peel” sign

bilious vomiting