Adaptive online self-gating (ADIOS) for free-breathing noncontrast renal MR angiography.
OBJECTIVE
To develop a respiratory self-gating method, adaptive online self-gating (ADIOS), for noncontrast MR angiography (NC MRA) of renal arteries to overcome some limitations of current free-breathing methods.


METHODS
A NC MRA pulse sequence for online respiratory self-gating was developed based on three-dimensional balanced steady-state free precession (bSSFP) and slab-selective inversion-recovery. Motion information was derived directly from the slab being imaged for online gating. Scan efficiency was maintained by an automatic adaptive online algorithm. Qualitative and quantitative assessments of image quality were performed and results were compared with conventional diaphragm navigator (NAV).


RESULTS
NC MRA imaging was successfully completed in all subjects (n = 15). Similarly good image quality was observed in the proximal-middle renal arteries with ADIOS compared with NAV. Superior image quality was observed in the middle-distal renal arteries in the right kidneys with no NAV-induced artifacts. Maximal visible artery length was significantly longer with ADIOS versus NAV in the right kidneys. NAV setup was completely eliminated and scan time was significantly shorter with ADIOS on average compared with NAV.


CONCLUSIONS
The proposed ADIOS technique for noncontrast MRA provides high-quality visualization of renal arteries with no diaphragm navigator-induced artifacts, simplified setup, and shorter scan time.
University of California, Los Angeles, Department of Bioengineering, Los Angeles, California, USA.|Cedars-Sinai Medical Center, Biomedical Imaging Research Institute, Department of Biomedical Sciences, Los Angeles, California, USA.
Yibin
Y
Xie
Cedars-Sinai Medical Center, Biomedical Imaging Research Institute, Department of Biomedical Sciences, Los Angeles, California, USA.
Zhaoyang
Z
Fan
Cedars-Sinai Medical Center, Department of Imaging, Los Angeles, California, USA.
Rola
R
Saouaf
Siemens Medical Solutions, Los Angeles, California, USA.
Yutaka
Y
Natsuaki
Siemens Medical Solutions, Los Angeles, California, USA.
Gerhard
G
Laub
University of California, Los Angeles, Department of Bioengineering, Los Angeles, California, USA.|Cedars-Sinai Medical Center, Biomedical Imaging Research Institute, Department of Biomedical Sciences, Los Angeles, California, USA.
Debiao
D
Li
D000328:Adult; D000465:Algorithms; D003287:Contrast Media; D005246:Feedback; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008875:Middle Aged; D009862:Online Systems; D010363:Pattern Recognition, Automated / Q000379:methods*; D012077:Renal Artery / Q000033:anatomy & histology*; D015203:Reproducibility of Results; D015656:Respiratory Mechanics; D055425:Respiratory-Gated Imaging Techniques / Q000379:methods*; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted; D013382:Subtraction Technique; D055815:Young Adult
D003287:Contrast Media
noncontrast MRA; online self-gating; renal MRA