[Assessment of renal arteries in patients suspected of having renovascular hypertension: comparison of Doppler sonography with multiphase MR angiography].

In 40 patients suspected of having renal artery stenosis Doppler ultrasound and multiphase magnetic resonance angiography (MRA) was performed. In 18 cases digital subtraction angiography, which served as a reference method, was performed. Use of multiphase MRA enabled technique, due to short acquisition time, acquisition of 3 phases of examination during a single breath-hold. Parameters of MR examination: field = 1.5T, TR = 5 ms, TE = 2 ms, number of slices = 30-35, slice thickness = 1 mm, field of view = 30 x 45 cm, matrix = 164 x 512. Visualization of main and accessory renal arteries, as well as presence and grade of stenosis was evaluated. In the group of 18 patients with 42 renal arteries, 23 stenoses and 8 accessory arteries were detected. Sensitivity and specificity of MRA in diagnosis of renal artery stenosis was 87% and 100%, of ultrasound 78% and 100%. During MRA examination, 7 accessory renal arteries were visualized, comparing to one detected by USG. Comparing to Doppler ultrasound, multiphase MRA has higher sensitivity and similar specificity in diagnosis of renal artery stenosis. Ultrasonography, contrary to MRA, has low sensitivity in diagnosis of accessory renal arteries.