PRESENTATION ON DEVELOPMENT OF DIGESTIVE SYSTEM AND ASSOCIATED DEVELOPMENTAL ANOMALIES

1. DEVELOPMENT OF DIGESTIVE
SYSTEM AND ASSOCIATED
DEVELOPMENTAL ANOMALIES
Dr. Maskur Ara Ferdouse
Anatomy, M.Phil. Part-I
Rangpur Medical College

2. Primitive Gut Tube
The digestive tract develops
from the primitive gut tube that
is derived from the dorsal part
of the endodermal yolk sac.

3. Development of foregut derivatives

4. Successive stages in the development of the respiratory diverticulum and
esophagus through partitioning of the foregut:

5. Clinical co-relation:
1)Esophageal atresia
2)Esophageal stenosis
3)Tracheoesophageal fistula
4)Achalashia cardia

8. Fig: CXR-Frontal View: Coiling up of introduced NG tube in the esophagus
with gas shadow in stomach.

9. Fig: CXR-Frontal View: Bird beak appearance in achalasia cardia

10. Stomach:
The stomach appears as a fusiform dilatation of foregut
distal to the esophagus in the fourth week of development.
The dilatation presents a ventral border, a dorsal border left
and right surfaces and an upper and lower end.

11. Changes in shape and position of stomach:
The changes in position of the stomach can be easily explained by
assuming that it rotates twice.
1)Around a longitudinal axis
2)Around an anteroposterior axis

12. Rotation of the stomach along its longitudinal axis and
anteroposterior axis

13. Changes in the mesenteries of the stomach due to its rotation

14. Clinical co-relation:
Congenital hypertrophic pyloric stenosis

15. Duodenum:
The duodenum develops from two sources-
1) The first and second part of the duodenum up to the
opening of the common bile duct develop from foregut.
2) The second part of the duodenum below the opening of
the common bile duct along with third and fourth part
develop from midgut.

17. Fig: Barium Meal X- Ray Abdomen showing deudenal cap

18. Clinical co-relation:
1)Duodenal stenosis
2)Duodenal atresia
3)Duodenal diverticuli

20. Double bubble sign

21. The Liver:
The liver, the largest gland in the body develops from
following three sources-
Parenchyma- Endoderm of hepatic bud .
Fibrous stroma - Mesenchyme of septum transversum .
Hepatic sinusoids - Absorption and broken umbilical and
vitelline vein.

23. Clinical co-relation:
Liver and GB abnormalities-

24. Development of pancreas:
Pancreatic Abnormalities:
The ventral pancreatic bud consists of two
components that normally fuse and rotate around the
duodenum so that they come to lie below the dorsal
pancreatic bud. Occasionally, however, the right
portion of the ventral bud migrates along its normal
route, but the left migrates in the opposite direction.
In this manner, the duodenum is surrounded by
pancreatic tissue, and an annular pancreas is
formed. The malformation sometimes constricts the
duodenum and causes compete obstruction
Accessory pancreatic tissue may be any where
from the distal end of the esophagus to the tip of the
primary intestinal loop. Most frequently, it lies in the
mucos of the stomach and in Meckel’s diverticulum,
where it may show all of the histological
characteristics of the pancreas itself.

25. Prearterial (cephalic ) :
Lower part of deuodenum
Jejunum.
Most part of the illeum.
Post arterial (Caudal) :
Terminal part of illeum.
caecum.
Appendix.
Ascending colon.
Right 2/3rd of transverse
colon.
Derivatives of midgut:

26. Development of the primary
intestinal loop is characterized by
rapid elongation, particularly of the
cephalic limb. As a result of the rapid
growth and expansion of the liver,
the abdominal cavity temporarily
becomes too small to contain all the
intestinal loops, and they enter the
extraembryonic cavity in the
umbilical cord during the sixth week
of development (physiological
umbilical herniation).
Physiological Herniation

27. Rotation of Midgut:

29. Development of cecum and appendix:

30. Body Wall Defect:

31. 1.Meckel’s diverticulum
2.Vitalline cyst or Enterocystoma
3. Umbilical fistula or Vitelline fistula
Vitelline duct abnormalities:

32. Gut Rotation Defects:
1)Reversed rotation of the intestinal loop.
2)Duplications of intestinal loop.
3)Gut atresia and stenosis.

34. Hindgut:
Cloacal region in embryos at successive stages of development

35. Hindgut abnormalities:
1)Congenital megacolon (Hirchprung’s disease)
2)Rectal fistula
3)Imperforate anus

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