Colon - Diagnosis/Imaging

Appendicitis

Diagnosis/Imaging 

-Adults (non- pregnant)

     - CT (w/IV contrast) - appendix >6mm

-Children and Pregnant Women

     -Ultrasound (modality of choice)

           -appendix >6mm           -periappendiceal fat changes 

           -free fluid       -appendicolith

      - CT and MRI

Diverticulosis

Imaging

- Colonoscopy - small openings, “pouches” in colonic wall

- CT and selectively Barium Enema

Diverticulitis

Imaging

- Contrast Enhanced CT (CE-CT)

     -first-line study

     -pericolic fat stranding (“dirty fat”) - hallmark sign

Ulcerative Colitis (UC)

Imaging 

-Colonoscopy (gold standard)

-abdominal x-ray - mucosal edema (“thumbprinting”)

-CT/MRI/BE - loss of haustration (“lead pipe” colon) in chronic UC

Crohn Colitis

Diagnosis/Imaging  

- Ileocolonoscopy, MRE/CTE, laboratory marker (all gold standard)

Ischemic Colitis (IC)

Imaging

-Colonoscopy - diagnostic gold standard 

-CT w/contrast - submucosal edema (“thumbprinting”)

Irritable Bowel Syndrome (IBS)

Imaging - not used for IBS

Diagnosis 

-symptom criteria - recurrent abdominal pain >1 day/week in last 3 months, w/2 or more of:

  -pain related to defecation

  -change in stool frequency

  -change in stool form

Colorectal Cancer

Imaging

- CT - first-line for staging 

-MRI

Large Bowel Obstruction (LBO)

Diagnosis/Imaging

- abdominal x-ray - dilated colon >12 cm (risk of perforation)

- CT: gold standard

Volvulus of the Colon

Diagnosis/Imaging 

-CT (preferred) - “whirl/whirlpool sign”

- abdominal x-ray - coffee bean appearance (sigmoid)

-BE - “birds beak”

-Ultrasound - markedly dilated bowel loops, whirlpool signs

Hemorrhoids

Surgical

-severe cases: excisional hemorrhoidectomy (gold standard for Grade III-IV)