Purpose To demonstrate the feasibility of free-breathing three-dimensional (3D) radial ultrashort echo time (UTE) magnetic resonance (MR) imaging in the simultaneous detection of @entity1151 ( @entity1151 ) and high-quality evaluation of @entity358 . Materials and Methods The institutional animal care committee approved this study. A total of 12 beagles underwent MR imaging and computed tomography (CT) before and after induction of @entity1151 with autologous clots. Breath-hold 3D MR angiography and free-breathing 3D radial UTE (1.0-mm isotropic spatial resolution; echo time, 0.08 msec) were performed at 3 T. Two blinded radiologists independently marked and graded all PEs on a four-point scale (1 = low confidence, 4 = absolutely certain) on MR angiographic and UTE images. Image quality of @entity358 was scored on a four-point-scale (1 = poor, 4 = excellent). Locations and ratings of emboli were compared with reference standard CT images by using an alternative free-response receiver operating characteristic curve (AFROC) method. Areas under the curve and image quality ratings were compared by using the F test and the Wilcoxon signed-rank test. Results A total of 48 emboli were detected with CT. Both readers showed higher sensitivity for @entity1151 detection with UTE (83% and 79%) than with MR angiography (75% and 71%). The AFROC area under the curve was higher for UTE than for MR angiography (0.95 vs 0.89), with a significant difference in area under the curve of 0.06 (95% confidence interval: 0.01, 0.11; P = .018). UTE image quality exceeded that of MR angiography for subsegmental arteries (3.5    0.7 vs 2.9    0.5, P = .002) and @entity358 (3.8    0.5 vs 2.2    0.2, P < .001). The apparent signal-to-noise ratio in @entity358 was significantly higher for UTE than for MR angiography (41.0    5.2 vs 24.5    6.2 [P < .001] and 10.2    1.8 vs 3.5    0.8 [P < .001], respectively). The apparent contrast-to-noise ratio between arteries and PEs was higher for UTE than for MR angiography (20.3    5.2 vs 15.4    6.7, P = .055). Conclusion In a @entity235 model, free-breathing 3D radial UTE performs better than breath-hold 3D MR angiography in the detection of @entity1151 and yields better image quality for visualization of small vessels and @entity358 . Free-breathing 3D radial UTE for detection of @entity1151 is feasible and warrants evaluation in @entity1 subjects. (  ) RSNA, 2015.

Pulmonary Embolism Detection with Three-dimensional Ultrashort Echo Time MR Imaging: Experimental Study in XXXX .

@entity235 :: ('9615', 'Species') :: ['canine'] @entity1 :: ('9606', 'Species') :: ['human'] @entity358 :: ('MESH:D008171', 'Disease') :: ['lung parenchyma', 'pulmonary arteries and lung parenchyma'] @entity1151 :: ('MESH:D011655', 'Disease') :: ['PE', 'pulmonary embolism']
@entity235 :: (9615,Species) :: ['Canines']
