摘要篇首： The nutcracker phenomenon refers to compression of the left renal vein between the aorta and the superior mesenteric artery, which results in renal venous hypertension and its clinical symptoms.1 This phenomenon is an unusual, but well-accepted cause of hematuria. As of now, it appears the nutcracker phenomenon is probably more common than previously suspected.2 To the best of our knowledge, however, there have been few trials investigating the use of multislice helical computed tomography angiography (CTA) of the renal vein along with measurements of the angles and distances between the aorta and the SMA in the diagnosis of the nutcracker phenomenon. The purpose of This work was to study the anatomic changes involved in the nutcracker phenomenon by comparing the vascular anatomy in patients with this phenomenon to that in healthy control subjects, and to assess the value of CTA in the diagnosis of this condition.