Types of Ileal Interposition

Types of Ileal Interposition

Our small intestines vary between 450 cm and 800 cm and consist of three parts: Duodenum, Jejunum and Ileum.
Duodenum creates first part of small intestines. Its length is between 20 to 25 cm. It starts just after the Pylorus muscle which controls gastric outlet. Jejunum creates second section of small intestine. Approximately 40% of small intestines is jejunum.
Ileum is the last part of small intestines. It connects small intestine into large intestine (colon). Approximately 60% of all small intestines consists of ileum.

Generally, length of duodenum (around 25 cm) is not considered in average intestinal length. Therefore, length of jejunum varies between 200 to 350 cm and length of ileum varies between 350 to 450 cm. It is not possible to differentiate jejunum and ileum visually. Exact differentiation point can not be noticed. Even cellular differentiation is not on a certain point. So we base on our preliminary acceptations while determining distances.

Small intestines are the main body part for food absorption but their functions extend beyond this. The small intestines and the digestive system has a strong hormonal impact on regulation of food absorption and process troughout the body. Different intestinal derived hormones (which are called incretins or secretins) play an important role in metabolic regulation. Therefore they have strong impact on formation and treatment of Type 2 Diabetes.

The purpose of Ileal Interposition surgeries as a sum, is to enhance the early stimulation of distal ileal segment with raw and undigested food. All tree different types of Interposition, bring the distal ileal segment to a close anatomical position in different ways.
I. Gastroileal Interposition with Bipartition (GIB)
II. Duodenoileal Interposition (DII)
III. Jejunoileal Interposition (JII)

I. Gastroileal Interposition (GIB) :
a. Ileal segment is connected directly to the stomach. Early and strong stimulation of distal ileum. (HINDGUT STIMULATION)
b. Duodenal anatomy is preserved.
c. ERCP is available after surgery.
d. Large gastroileal anastomoses enhances food to be directed mainly to ileal segment. By this way duodenum is kept away from food. The negative incretin secretion is suppressed. (FOREGUT SUPRESSION!)
e. All the bowels are in contact with food. Moreover the ileal segment which becomes the main route of stomach drainage, diverts all its material to the very beginning of jejunum. That’s why there is NO MALABSORPTION RISK.

II. Duodenoileal Interposition :
a. The ileum is connected to postpyloric duodenum.
b. Duodenum is transected and diverted from food.
c. Duodenum is definetly excluded from food.
f. ERCP becomes impossible due to anatomical exclusion of duodenum!
g. Its almost Irreversable.

III. Jejunoileal Interposition :
a. The ileum is connected to jejunum after Treitz ligment.
b. Duodenum is preserved and stay directly connected with food.
c. NO FOREGUT SUPRESSION! (Less Antidiabetic Effect).
e. ERCP is available!
f. Totally Reversable.