93. Colon Flashcards
Which artery supplies the proximal half of the descending colon?
B) Middle colic artery
In cats, the cecocolic orifice is located:
B) Adjacent to the ileocolic orifice
Which of the following structures tethers the descending colon to the ascending duodenum?
A) Duodenocolic ligament
Which portion of the colon is primarily involved in fecal storage?
D) Distal colon
Which cells are responsible for mucus secretion in the colon?
A) Goblet cells
In which species is the cecum short and comma-shaped?
B) Cats
Which of the following is the most common cause of feline megacolon?
B) Idiopathic
What is the primary function of short-chain fatty acids in the colon?
B) Absorb Na+ and Cl-
Which layer of the colon is most important for tensile strength during healing?
B) Submucosa
What is the recommended suture pattern for colonic anastomosis?
A) Simple interrupted
The mesocolon is shortest at the level of the right colic flexure.
False
The colonic epithelium is involved in both absorption and secretion functions.
True
Colonic transit is slower than that of the small intestine, allowing time for fecal mixing.
True
The left colic artery supplies the proximal portion of the transverse colon.
False
The colon of cats contains numerous aggregated lymphoid nodules similar to those in the small intestine.
False
A biofragmentable anastomosis ring provides an inverted wound with high bursting strength.
True
Fibrin glue has been shown to have consistently positive results for colonic sealing in veterinary patients.
False
Colonic mucosa is composed of columnar and cuboidal epithelial cells arranged in parallel crypts.
True
A major component of colonic secretion is K+ and bicarbonate (HCO3-).
True
The cranial mesenteric artery supplies the majority of the colon.
False
Describe the role of the vasa recta in colonic blood supply.
The vasa recta bifurcate and supply blood to the muscular and submucosal layers.
What is the primary clinical sign of idiopathic megacolon in cats?
Severe constipation and obstipation.
What surgical procedure is indicated for cecal neoplasia in dogs?
Typhlectomy.
Which diagnostic imaging technique is best for identifying colonic polyps?
Colonoscopy.
What are the main functions of goblet cells in the colon?
Secretion of mucus.
Name two common indications for colectomy in cats.
Megacolon, neoplasia.
What is the function of the ileocolic junction?
Prevents reflux of colonic contents into the small intestine.
What is the significance of aldosterone in colonic sodium absorption?
Enhances sodium absorption via amiloride-sensitive sodium channels.
What is the role of the cranial rectal artery in colonic vasculature?
Supplies the distal descending colon and rectum.
How does colonic wound strength compare to that of the small intestine during healing?
Colonic wound healing is slower than the small intestine, with strength returning to 75% at 4 months.
A cat presents with chronic obstipation and megacolon. What medical management options are available before considering surgery?
Stool softeners, prokinetics, manual evacuation.
A dog presents with colonic volvulus. What are the key clinical signs and imaging findings?
Abdominal distension, gaseous distension on radiographs.
You are performing a subtotal colectomy in a cat with megacolon. What considerations should you have regarding the ileocolic junction?
Preserving the ileocolic junction reduces the risk of small intestinal bacterial overgrowth.
What complications can arise from a combined abdominal transanal pull-through procedure for colorectal tumors?
Wound dehiscence, fecal incontinence.
In a dog with a colonic tumor, why might you perform a CT scan prior to surgery?
To assess tumor size, invasion, and potential metastasis.
Which antibiotic is recommended for perioperative prophylaxis in colonic surgery?
C) Cefoxitin
Which of the following is a risk factor for colonic wound dehiscence?
A) Hypoperfusion
Which diagnostic method is best suited for evaluating submucosal colonic lesions?
A) Ultrasound
What is the most likely complication after colopexy?
D) Fecal incontinence
In which type of colonic neoplasia is immunohistochemistry most useful?
B) Gastrointestinal stromal tumors (GIST)
Postoperative hemorrhage is a common complication of biofragmentable anastomosis rings.
False
Cats with megacolon often respond well to long-term medical management alone.
False
Colonic anastomosis using staples tends to result in more fibrosis compared to sutures.
False
The cranial mesenteric artery supplies the entire transverse colon.
False
The submucosa is the weakest layer of the colon.
False
