Nonenhanced Renal Artery MR Angiography With Time Spatial Labeling Inversion Pulse Technology And Its Clinical Values

Objective To evaluate the feasibility of nonenhanced renal artery MR angiography（MRA）with respiratory-gated time spatial labeling inversion pulse（Timeslip）and its clinical application.Methods Forty-eight consecutive patients underwent the 3.0 T MRI（TOSHIBA EXCELART Vantage）examination to visualize renal artery with contrast-enhanced MRA（CEMRA）and the examination with Time slip technology.Signal to noise ratio（SNR）and contrast to noise ratio（CNR）was measured on CEMRA and Time-slip images,respectively.Two experienced radiologists assessed the imaging quality of renal artery MRA on 3D-MIPs reconstructed images.Results 96 renal arteries and 4 accessory renal arteries in 48 patients were visualized on both Time slip and CEMRA.SNR values on Time slip and CEMRA were 106.4±15.8 and 86.1±16.3（t=-4.353,P<0.001）;CNR were 99.1±17.5 and 80.2±17.4（t=-4.619,P<0.001）,respectively.Timeslip MIP images obtained higher quality than CEMRA did（Z=-2.246,P=0.018）,and venous contamination was sharply reduced on Time-slip technology when compared with CEMRA（Z=-4.749,P<0.001）.Conclusion Non-enhanced renal artery MRA with respiratory-gated Time-slip technology can provide higher SNR images of renal artery than conventional CEMRA,which can provide more information for clinical decision making.