The whirlpool sign of the mesentery, also known as the whirl sign, is seen when the bowel rotates around its mesentery leading to whirls of the mesenteric vessels.
The term whirlpool sign is used in other contexts: see whirlpool sign (disambiguation).
It is seen in a number of settings:
malrotation complicated by midgut volvulus
- it represents the swirling appearance of the mesentery and superior mesenteric vein around the superior mesenteric artery. The direction of swirl is clockwise on ultrasound (viewed from above so-to-speak) and counter-clockwise on CT (as if viewed from below)
- it is the corollary of the corkscrew sign seen on barium studies.
cecal volvulus and cecal bascule
- cecal volvulus and cecal bascule can have the same appearance, with whirl occurring in the cecal mesentery
- sigmoid volvulus 6
- closed loop bowel obstruction 5
- enteritis: similar pattern, but in the opposite direction has been described on ultrasound 3
- omental torsion 7
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- 2. Peterson CM, Anderson JS, Hara AK et-al. Volvulus of the gastrointestinal tract: appearances at multimodality imaging. Radiographics. 29 (5): 1281-93. doi:10.1148/rg.295095011 - Pubmed citation
- 3. Shimanuki Y, Aihara T, Takano H et-al. Clockwise whirlpool sign at color Doppler US: an objective and definite sign of midgut volvulus. Radiology. 1996;199 (1): 261-4. Radiology (abstract) - Pubmed citation
- 4. Frank AJ, Goffner LB, Fruauff AA et-al. Cecal volvulus: the CT whirl sign. Abdom Imaging. 1993;18 (3): 288-9. - Pubmed citation
- 5. Duda JB, Bhatt S, Dogra VS. Utility of CT whirl sign in guiding management of small-bowel obstruction. AJR Am J Roentgenol. 2008;191 (3): 743-7. doi:10.2214/AJR.07.3386 - Pubmed citation
- 6. Levsky JM, Den EI, DuBrow RA et-al. CT findings of sigmoid volvulus. AJR Am J Roentgenol. 2010;194 (1): 136-43. doi:10.2214/AJR.09.2580 - Pubmed citation
- 7. Tandon AA, Lim KS. Torsion of the greater omentum: A rare preoperative diagnosis. Indian J Radiol Imaging. 2010;20 (4): 294-6. doi:10.4103/0971-3026.73540 - Free text at pubmed - Pubmed citation