Imaging recommendation · Abdomen · Pelvis

Acute left lower quadrant pain

Q: What's the alternative imaging for acute left lower quadrant pain when suspected fistula or complicated?

CT — CT with IV + rectal contrast (iv contrast).

Q: What's the alternative imaging for acute left lower quadrant pain when pregnancy?

MRI — MRI abdomen/pelvis without contrast (no contrast).

Recommended: CT Abdomen/Pelvis with IV contrast is the preferred imaging study for acute left lower quadrant pain. First-line for evaluating left lower quadrant pain.

Recommended study

CT Abdomen/Pelvis with IV contrast

CT IV contrast Preferred Abdomen · Pelvis EmergencyAcute inpatient Reviewed 2026-05

First-line for evaluating left lower quadrant pain. Oral contrast optional. Include rectal contrast when fistula or complicated process is suspected.

If the default doesn't apply

Suspected fistula or complicated

CT CT with IV + rectal contrast IV contrast

Pregnancy

MRI MRI abdomen/pelvis without contrast No contrast

Watch-outs

Free air or sealed perforation

Indicates Hinchey III–IV; surgical consultation needed.

First episode in young patient

Higher rate of recurrence/complications; consider colonoscopy after acute episode resolves to exclude malignancy.

Pearls

Hinchey classification (I–IV) guides medical vs surgical management.
Right-sided diverticulitis more common in Asian populations and can mimic appendicitis.
Colonoscopy is contraindicated in acute diverticulitis (perforation risk) — delay 6 weeks.