Abstract :
Objectives: Nutcracker phenomenon is caused by the compression of left renal vein between the superior mesenteric artery and the aorta. There are also variants namely the ‘posterior nutcracker phenomenon’ where the posteriorly located retroaortic or circumaortic left renal vein is compressed between the aorta and the vertebral body. The aim of this study is to define the vascular alterations in veins other than the left renal vein secondary to anterior and posterior nutcracker phenomena and emphasize their contribution to the diagnosis. Method: A total of 258 patients were enrolled in the study. Computed tomography images of 57 patients with nutcracker phenomenon were retrospectively investigated for the presence of secondary vascular alterations. In addition, images of 169 patients with a retroaortic and 32 patients with a circumaortic left renal vein variation were searched for the presence of a posterior nutcracker phenomenon and associated secondary vascular findings. Results: Dilatation of left gonadal (n: 15, 26%), left lumbar or ascending lumbar (n: 9, 16%), hemiazygos/accessory hemiazygos (n: 4, 7%), left suprarenal (n: 4, 7%), and inferior phrenic (n:2, 4%) veins were seen in anterior nutcracker phenomenon. Pelvic varices/varicoceles and pseudothrombosis in the left renal vein were present in 7(12%) and 4 ( 7%) patients, respectively. 14% of 169 patients with a retroaortic left renal vein and 16% of 32 patients with circumaortic left renal vein showed a posterior NC phenomenon and associated vascular alterations. Conclusions: Awareness of the secondary vascular findings in nutcracker phenomenon may aid in the diagnosis and guide management.
NaturalLanguageKeyword :
Nutcracker phenomenon , posterior nutcracker phenomenon , computed tomography , computed tomography angiography