Renal artery pseudoaneurysm

Giant,
sporadic, multicentric, locally aggressive, renal angiomyolipoma, complicated by emphysematous pyelonephritis, psuedoaneurysm and Wunderlich syndrome. CECT sagittal section through the lesion shows pooling of intravenous contrast within the lesion suggestive of pseudo-aneurysm formation.
www.eurorad.org • CC by-nc-sa-4.0
Giant,
sporadic, multicentric, locally aggressive, renal angiomyolipoma, complicated by emphysematous pyelonephritis, psuedoaneurysm and Wunderlich syndrome. CECT sagittal section through the lesion shows pooling of intravenous contrast within the lesion suggestive of pseudo-aneurysm formation.
www.eurorad.org • CC by-nc-sa-4.0
Endovascular
intervention in renovascular disease: a pictorial review. Axial CT (a, long white arrow) and angiographic (b, black arrow) images of a left intraparenchymal renal artery pseudoaneurysm subsequent to partial nephrectomy for renal tumour. The propensity for severe haemorrhage with these lesions warranted selective coil embolisation (c, white arrow)
insightsimaging.springeropen.com • Open Access
Radiopaedia • CC-by-nc-sa 3.0 • de

Renal artery pseudoaneurysms are uncommon vascular finding, with the majority occuring after a renal intervention.

Pathology

A renal artery pseudoaneurysm differs from a renal artery true aneurysm (as might occur in fibromuscular dysplasia) in that it does not involve all three layers of the arterial wall, but rather involves an outpouching through one or more layers of the wall.

Renal artery pseudoaneuryms occur most commonly following an intervention, such as partial nephrectomy or percutaneous nephrostomy. A pseudoaneurysm may complicate renal transplantation. Rarely, they may occur from infection (possibly after renal artery stent placement).

Radiographic features

Ultrasound
  • focal dilatation of the renal artery 
  • if large, there may be a yin-yang swirling within the pseudoaneurysm
CT/MRI
  • focal dilatation off the renal artery on a contrast-enhanced study
Digital subtraction angiography (DSA)
  • abnormal well-defined saccular outpouching off the renal artery during a selective renal artery angiogram

Treatment and prognosis

Treatment decisions are individualized to the patient; women who plan to become pregnant are considered to be at higher risk. If large (>2 cm), asymptomatic, and a branch vessel it can be treated with coil embolization  (although aneurysms smaller than 2 cm have ruptured). Main renal artery pseudoaneurysms may require a stent or surgical ligation.

If symptomatic, more aggressive therapy may be indicated, including surgery.

Siehe auch:
Assoziationen und Differentialdiagnosen zu Aneurysma spurium der Arteria renalis:
Embolisation
Aneurysma spurium der Arteria renalis
insightsimaging.springeropen.com • Open Access