|LETTER TO EDITOR
|Year : 2021 | Volume
| Issue : 1 | Page : 222
The yin-yang sign: Footprint in diagnosis of pseudoaneurysm
Suvarna Deshpande, Suresh Phatak
Department of Radiodiagnosis, Jawaharlal Nehru Medical College, Datta Meghe Institute of Medical Sciences (Deemed to be University), Wardha, Maharashtra, India
|Date of Submission||28-Apr-2020|
|Date of Decision||20-Dec-2020|
|Date of Acceptance||18-Jan-2021|
|Date of Web Publication||29-Jul-2021|
Dr. Suresh Phatak
Department of Radiodiagnosis, Datta Meghe Institute of Medical Sciences, Sawangi (M) Wardha, Maharashtra
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Deshpande S, Phatak S. The yin-yang sign: Footprint in diagnosis of pseudoaneurysm. J Datta Meghe Inst Med Sci Univ 2021;16:222
When there is a focal or diffuse dilatation of an artery to more than its 50% diameter, an aneurysm is formed. It can be of two types, true: Where all layers of the arterial wall are involved and false: Where all layers of the arterial wall are not involved. Most of these aneurysm grow rapidly and are asymptomatic, so their diagnosis plays a very vital role for further management. In false aneurysm (pseudoaneurysm), there are high chances of the development of thrombus and so filling by blood occurs only in a part of lesion [Figure 1].
|Figure 1: Gray scale ultrasound shows a hypoechoic lesion of size 36 mm × 20 mm with most of its lumen occupied by thrombus. Small partial lumen is visualized|
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Pseudoaneurysm is diagnosed on Doppler ultrasound or computed tomography with the help of “the yin-yang sign.” This sign is an ancient Chinese symbol which is alluded in radiology for evaluation of aneurysmal vascular structures. The yinyang sign is produced on color Doppler due to the presence of swirling and turbulent movement of bidirectional blood flow as red color is produced by the blood flowing toward transducer and blue color is produced by blood flowing away from the transducer. Thus, this sign on Doppler ultrasound helps in the swift diagnosis of pseudoaneurysm and avoid its further complication [Figure 2].
|Figure 2: Color Doppler showing classical yin yang sign (flow towards and away from the transducer in residual lumen in branch of external carotid artery)|
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Conflicts of interest
There are no conflicts of interest.
| References|| |
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[Figure 1], [Figure 2]