TY - GEN
T1 - Optimization of combination of voxel size and flip angle by visual evaluation for renal magnetic resonance angiography without a contrast agent
AU - Kida, K.
AU - Goto, S.
AU - Azuma, Y.
N1 - Copyright:
Copyright 2021 Elsevier B.V., All rights reserved.
PY - 2009
Y1 - 2009
N2 - To improve spatial resolution of renal magnetic resonance (MR) angiography, we attempted to use MR signals before reaching steady state in balanced turbo field echo (b-TFE) sequence. An isotropic protocol (isotropic voxel size; 0.78 mm) was constructed, but the loss of contrast to noise ratio (CNR) was not avoided though we employed the dedicated k-space scheme. The trade-off of the spatial resolution and CNR is difficult to decide by numerical value only, and it is necessary to introduce evaluation of clinical images for the determination of a flip angle. In this study, we investigated the optimal combination of voxel size and flip angle using visual evaluation in order to obtain a good balance of the spatial resolution and CNR. A paired comparison method was employed as visual evaluation. As a result, the highest scale-value of available combination of isotropic voxel size and flip angle was 0.67 mm and 60 degrees. This isotropic protocol of the highest resolution for MR angiography of renal arteries using contrast behavior during the transient phase of b-TFE sequence will be useful in the clinical field.
AB - To improve spatial resolution of renal magnetic resonance (MR) angiography, we attempted to use MR signals before reaching steady state in balanced turbo field echo (b-TFE) sequence. An isotropic protocol (isotropic voxel size; 0.78 mm) was constructed, but the loss of contrast to noise ratio (CNR) was not avoided though we employed the dedicated k-space scheme. The trade-off of the spatial resolution and CNR is difficult to decide by numerical value only, and it is necessary to introduce evaluation of clinical images for the determination of a flip angle. In this study, we investigated the optimal combination of voxel size and flip angle using visual evaluation in order to obtain a good balance of the spatial resolution and CNR. A paired comparison method was employed as visual evaluation. As a result, the highest scale-value of available combination of isotropic voxel size and flip angle was 0.67 mm and 60 degrees. This isotropic protocol of the highest resolution for MR angiography of renal arteries using contrast behavior during the transient phase of b-TFE sequence will be useful in the clinical field.
KW - Isotropic protocol
KW - Paired comparison method
KW - Renal MR angiography
KW - Spatial resolution
KW - Transient phase
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U2 - 10.1007/978-3-642-03879-2_103
DO - 10.1007/978-3-642-03879-2_103
M3 - Conference contribution
AN - SCOPUS:77950870480
SN - 9783642038785
T3 - IFMBE Proceedings
SP - 364
EP - 367
BT - World Congress on Medical Physics and Biomedical Engineering
PB - Springer Verlag
T2 - World Congress on Medical Physics and Biomedical Engineering: Diagnostic Imaging
Y2 - 7 September 2009 through 12 September 2009
ER -