MR angiography of renal vascular malformations

We wanted to determine whether three-dimensional phase contrast (3DPC) MR angiography is clinically useful in the diagnosis of renal vascular malformations.

Three-dimensional PC MR angiography was performed in 22 patients with gross hematuria and in 8 healthy volunteers. Small flip angles and 60 cm/s velocity encoding best demonstrated the normal intrarenal arteries with arteriovenous differentiation in the eight healthy volunteers. In the 22 patients with gross hematuria, intraarterial digital subtraction angiography demonstrated cirsoid-type malformations in 6 patients, aneurysmal-type malformations in 3 patients, and normal vascular anatomy in 13 patients.

Magnetic resonance angiography detected all three aneurysmal-type malformations and four of the cirsoid-type malformations. Small cirsoid-type malformations were not detected in two patients. The moderate or large malformations were demonstrated as dilated and tortuous feeding arteries and high intensity renal veins with high flow velocity. We found no correlation between signal intensity in the suprarenal inferior vena cava and the presence of arteriovenous shunts. There were no false-positive cases.

Sensitivity, specificity, and accuracy in this series were 78, 100, and 91%, respectively.