Shadi A Esfahani MD,MPH, Presenter: Nothing to Disclose

David K. Yousefzadeh MD, Abstract Co-Author: Nothing to Disclose

To illustrating that the pseudo-whirlpool sign (PWS) is caused by rightward jejunum (RWJ) and swirling of the jejunal vein (JV) not the swirling of the superior mesenteric vein (SMV).

A retrospective review of abdominal CT images was performed in 128 patients without malrotation or heterotaxia. Types of jujonal vein (JV), anatomic classification of JV, orientation of superior mesenteric vein and artery (SMV and SMA), and position of D3 between Aorta (AO) and SMA (to exclude incidental malrotation) were evaluated in two groups of patients with RWJ and leftward jejunum (LWJ). Statistical analysis was performed regarding the linkage between findings in RWJ versus LWJ, using Chi Square test. 

Of 128 pediatric patients (F/M: 60/68), 86 children had LWJ, showing the JV runs either between SMA and AO (Type Ia) or anterior to SMA (type IIa) before joining the SMV. None had PWS. Of 42 patients with RWJ, 35 had PWS with rightward JV swirling around SMA before joining the SMV (type Ib). In remaining 7 ones without PWS, right JV did not swirl around SMA before joining SMV (type IIb). SMV was always vertically oriented irrespective of presence or absence of PWS. PWS disappeared or reappeared as the jejunum flipped from one side to another in 7 children.

This primary study suggests that the PWS occurs due to the swirling of type Ib JV in RWJ despite the WS appearance as a result of SMV swirling. As the RWJ became LWJ after the treatment, the PWS disappeared and types Ib & IIb JV became types Ia and IIa. This sign was not seen in patients with LWJ and showed to be clinically inconsequential in patients with RWJ.

The pseudo whirlpool sign, associated with rightward shift of the jejunum does not indicate malrotation and warrant no further imaging studies.

Esfahani, S, Yousefzadeh, D, Distinction between the Ominous Whirlpool Sign and Pseudo Whirlpool Sign: Swirling of Superior Mesenteric vs the Jejunal vein.  Radiological Society of North America 2012 Scientific Assembly and Annual Meeting, November 25 - November 30, 2012 ,Chicago IL. http://archive.rsna.org/2012/12034184.html