What causes Hurricane sign in abdomen on CT?
Let me know in the comments.
Click to reveal the answer
Answer:
Whirlpool-like (also called the Hurricane sign) swirling appearance of bowel loops and mesentery around the superior mesenteric artery (SMA) in midgut volvulus, a surgical emergency due to intestinal malrotation; also described in some cases of portal venous gas where gas outlines mesenteric vessels in a swirling pattern.
Why is it called so?
Named for its resemblance to the swirling clouds and eye of a hurricane on weather radar, reflecting the characteristic rotational distortion of vascular and bowel structures around a central axis. The term Hurricane sign visually conveys the concentric, rotating configuration seen on CT.
Pathophysiology
Midgut volvulus arises from incomplete rotation and fixation of the midgut during embryonic development, allowing the small bowel mesentery to twist around the SMA axis; this produces a “corkscrew” or whirlpool configuration visible on CT as clockwise or counterclockwise swirling of bowel and mesentery superior to the SMA origin. In portal venous gas, intraluminal gas extends into mesenteric veins, accentuating the swirling vascular pattern amid edematous bowel.
Alternative names: Whirlpool sign, corkscrew sign
Other associated named signs: SMV inversion, beak sign
Access all radiology signs posted so far: https://radiogyan.com/radiology-signs/
Improve Content And Help Your Colleagues!
Found an error in the post? Please let us know using our contact page and we will update it with due credits!
If you wish to contribute radiological images for this case (or any other article on the website), you can submit them here and you will be duly credited: Submit radiology case