PMC5338909_01
3D 360  transanal ultrasound. (A) Low rectum. (B) Superior anal canal at the staple line. It is evident the image of double track hypoechoic and hyperechoic around an hypoechoic fluid collection. (C-D) Rendering 3D images with airy spots more inside the fluid collection.
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PMC5338909_01_gr1.jpg
fig0005
The patient underwent 3D 360  transanal ultrasound (t-US) which demonstrated a 6 x 3 cm right lateral pararectal fluid collection with an atypical stratification of its wall that results very similar to rectal duplication (Fig. 1).