Jejunum & Ileum & Large Intestine Flashcards
Distal 3/5, ends at the ileocecal junction
Lies in the RLQ
Villi: short, club-shaped
Intestinal glands (crypts): <3cm diameter
Circular folds: small, few, disappear distally
Location: hypogastric & inguinal region, right side
Vasa recta: short
Prominent Peyer patches, Vitamin B12 absorption
Ileum
Proximal 2/5 , begins at the duodenojejunal flexure
Lies in the LUQ
Villi: Long finger-like
Intestinal glands (crypts): >3cm diameter
Circular folds: large, numerous palpable
Location: umbilical region, left side of abdomen
Vasa recta: long
Often empty, thicker walls, more vascular/redder than ileum
Jejunum
6-7 meters long
Jejunum & Ileum
Blood supply of JEJUNUM & ILEUM
SUPERIOR MESENTERIC ARTERY from the abdominal aorta at level L1, sending 15-18 branches which unite to form loops
ARTERIALARCADES that gives rise to VASA RECTA
What anatomic features permits the surgeons to distinguish the ileum from other parts of the small intestine?
It has more fat in its mesentery than the jejunum
Characteristic of JEJUNUM
Deeper red
2-4cm
Thick and heavy
Greater vascularity
Long vasa recta
Few, large arcades
Less fat
Large, tall plicaecircularis
Few lymphoid nodules
Characteristic of ILEUM
Paler pink
2-3cm
Thin and light
Less vascularity
Short vasa recta
Many arcades
More fat
Low, sparse-absent in distal
Many lymphoid nodules
Part of the small intestine invaginates into an adjacent distal segment (intussuscipiens)
May be jejunoileal, ileoileal or most commonly, ileocecal
More common in children; may be caused by hyperplasia of lymphatic tissue in the wall of ileum
Obstructed bowel, right sided colicky pain, abdominal distention and hematochezia
Intussusception
Villi: none
Intestinal glands (crypts): 6-9cm diameter
Circular folds: none
Colon
Taenia coli
- 3 longitudinal bands of smooth muscle
Appendices epiploicae
- fatty tags
Haustra
- sacculations of the wall separated by plicae semilunaris
Large intestine
Hypersensitivity to gluten & gliadin protein (wheat, other grains) –> lymphocytes, plasma cells macrophages, eosinophils in lamina propria
Anti-gliadin antibodies in blood
SSX: chronic diarrhea, flatulence, weight loss, fatigue
Celiac disease
Chronic granulomatous inflammatory bowel disease –> linear, serpentine ulcers with skip areas
MC site: ileum
SSX: RLQ mass, diarrhea, refer, weight loss, weakness
Complications: strictures, fistulas
Crohn’s disease
Appendix is intraperitoneal, suspended by mesoappendix
McBurney point: midpoint of the line from R anterior superior iliac spine (ASIS) to umbilicus
Appendicitis
Dilatation of transverse colon –> perforation
SSX: abdominal pain, fever, leukocytosis
Toxic megacolon
Dilatation of cecum
Often in critically ill, bed ridden patients
Ogilvie syndrome
