Mesenteric Small Bowel, Colon, and Appendix Flashcards
The mesenteric small intestine is a tube approximately ___ meters long that lies totally within the greater peritoneal cavity.
7 meters long
The small bowel mesentery is composed of what different structures?
Composed of connective tissue, blood vessels, and lymphatic vessels and is covered by peritoneum, which reflects from the posterior parietal peritoneum
The root of the small bowel mesentery extends from where to where?
It extends obliquely from the ligament of Treitz, just left of the L2 vertebra, to the cecum, near the right sacroiliac joint.
Difference between jejunum and ileum.
The jejunum has a feathery mucosal pattern, more prominent valvular conniventes, wider lumen, and a thicker wall.
The ileum has a less featured mucosal pattern, thinner, less frequent folds, narrower lime, thinner, less frequent folds, narrower lumen, and a thinner wall.
This consists of the cecum and appendix, colon, rectum, and anal canal.
Large intestine
The large intestine is approximately how many meters in length from the ileum to the anus?
1.5 m
The large intestine is characterized by the _________, three longitudinal bands of muscle that traverse the colon shortening it to form the haustra, the sacculations created by puckering of the bowel wall.
Taenia coli
The _______ and ______ absorb water from the highly liquid material received from the ileum.
Cecum and ascending colon
It is a large blind pouch that extends below the level of the ileocecal valve.
Cecum
The cecum generally lies in the right iliac fossa but may be quite mobile.
It is covered on all sides by peritoneum (intraperitoneal), may be fixed extraperitoneally, covered only on its ventral surface by peritoneum.
It is a long worm-like tube that hangs from near the apex of the cecum.
Appendix
The ________ is extraperitoneal, lying in the anterior pararenal space, covered only on its central surface by the peritoneum.
Ascending colon
The hepatic flexors forms two curves. What are these curves?
The proximal, more posterior curve is closely related to the descending duodenum and right kidney.
The more distal anterior curve is closely related to the gallbladder.
This structure is intraperitoneal and suspended from the transverse mesocolon that arises from the peritoneum covering the pancreas and sweeps transversely across the upper abdomen.
Transverse colon
This structure limits the superior extent of the small bowel loops.
Transverse mesocolon
This colonic structure is closely related to the tail of the pancreas and the caudal aspect of the spleen.
Splenic flexors
The splenic flexure is anchored to the diaphragm by what ligament?
Phrenicocolic ligament
Which serves as a boundary between disease processes of the left subphrenic space the left paracolic gutter.
The sigmoid colon penetrates the peritoneum at the level of vertebrae _______ to continue as the extraperitoneal rectum.
S-2 to S-4
The rectums extends approximately how many cm?
12 cm
Peritoneum forming the ___________ covers the ventral and lateral aspects of the rectum.
Pouch of Douglas
The anal canal is approximately how many cm long?
3 to 4 cm
It is invested by the sphincter ani and lavator ani muscles.
A series of vertical folds in the rectum forms the ________.
Rectal columns of Morgagni
Beneath of which are the veins that when dilated are hempprhoids.
The thickness of the wall of the normal colon does not exceed ____ mm.
5 mm
Where does the appendix arise?
From the posteromedial aspect of the cecum at the junction of the taenia coli, approximately 1 to 2 cm below the ileocecal valve.
It is a blind-ended tube that is 4 to 5 mm in diameter and approximately 8 cm in diameter in length.
Appendix
May be up to 30 cm long.
A posterior position of the ileocecal valve indicates what position of the appendix?
Posterior position of the appendix
The appendix always arises from the cecum on the same side of as the ileocecal valve.
On CT, US, and MR, the appendix appears as a thin-walled tube less than ____ mm in diameter.
6 mm
