Ureteropelvic junction obstruction in lower pole moiety of duplex kidney
Presentation
Left loin pain
Patient Data
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Cystic mass at lower pole of left kidney
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![This study is a stack](/packs/stack-YQKLCKBI.gif)
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![This study is a stack](/packs/stack-YQKLCKBI.gif)
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Delayed 20 minutes post-injection of contrast, imaged supine and prone.
Duplex left collecting system with a ureteropelvic junction (UPJ) obstruction in the lower pole moiety - no ureter identified in the lower pole. Non-filling of lower pole ureter even in the prone position.
![](https://prod-images-static.radiopaedia.org/images/51566381/29dbf073c78e865afdd171777794f6_big_gallery.jpeg)
Pre-operative MAG3 nuclear renogram: delayed filling and emptying of left lower pole moiety.
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Post-pyleoplasty MAG3 renogram: filling and emptying of left lower pole moiety much improved after Lasix injection.
Post pyeloplasty MAG3 statistics: note rapid clearance from left kidney post-Lasix injection at 22 minutes