Cloud-processed 4D CMR flow imaging for pulmonary flow quantification.
OBJECTIVE
In this study, we evaluated a cloud-based platform for cardiac magnetic resonance (CMR) four-dimensional (4D) flow imaging, with fully integrated correction for eddy currents, Maxwell phase effects, and gradient field non-linearity, to quantify forward flow, regurgitation, and peak systolic velocity over the pulmonary artery.


METHODS
We prospectively recruited 52 adult patients during one-year period from July 2014. The 4D flow and planar (2D) phase-contrast (PC) were acquired during same scanning session, but 4D flow was scanned after injection of a gadolinium-based contrast agent. Eddy-currents were semi-automatically corrected using the web-based software. Flow over pulmonary valve was measured and the 4D flow values were compared against the 2D PC ones.


RESULTS
The mean forward flow was 92 (±30) ml/cycle measured with 4D flow and 86 (±29) ml/cycle measured with 2D PC, with a correlation of 0.82 and a mean difference of -6ml/cycle (-41-29). For the regurgitant fraction the correlation was 0.85 with a mean difference of -0.95% (-17-15). Mean peak systolic velocity measured with 4D flow was 92 (±49) cm/s and 108 (±56) cm/s with 2D PC, having a correlation of 0.93 and a mean difference of 16cm/s (-24-55).


CONCLUSIONS
4D flow imaging post-processed with an integrated cloud-based application accurately quantifies pulmonary flow. However, it may underestimate the peak systolic velocity.
Department of Radiology, Erasmus MC, Rotterdam, The Netherlands; Department of Cardiology, Erasmus MC, Rotterdam, The Netherlands. Electronic address: ralucachelu@hotmail.com.
Raluca G
RG
Chelu
Department of Radiology, Erasmus MC, Rotterdam, The Netherlands; Department of Radiology, Aga Khan University Hospital, Nairobi, Kenya.
Kevin W
KW
Wanambiro
Department of Radiology, University of California, San Diego, CA, USA.
Albert
A
Hsiao
Department of Radiology, Erasmus MC, Rotterdam, The Netherlands; Department of Cardiology, Erasmus MC, Rotterdam, The Netherlands.
Laurens E
LE
Swart
Department of Radiology, Erasmus MC, Rotterdam, The Netherlands.
Teun
T
Voogd
Department of Cardiology, Erasmus MC, Rotterdam, The Netherlands.
Allard T
AT
van den Hoven
Department of Cardiology, Erasmus MC, Rotterdam, The Netherlands.
Matthijs
M
van Kranenburg
Department of Radiology, Erasmus MC, Rotterdam, The Netherlands; Department of Cardiology, Erasmus MC, Rotterdam, The Netherlands.
Adriaan
A
Coenen
Department of Radiology, Erasmus MC, Rotterdam, The Netherlands; Department of Radiology, University Hospital, Genoa, Italy.
Sara
S
Boccalini
Department of Radiology, Erasmus MC, Rotterdam, The Netherlands.
Piotr A
PA
Wielopolski
MR Applications and Workflow - Europe, GE Healthcare B.V. Hoevelaken, The Netherlands.
Mika W
MW
Vogel
Department of Radiology, Erasmus MC, Rotterdam, The Netherlands.
Gabriel P
GP
Krestin
Department of Radiology, Stanford University, Stanford, CA, USA.
Shreyas S
SS
Vasanawala
Department of Radiology, Erasmus MC, Rotterdam, The Netherlands; Department of Cardiology, Erasmus MC, Rotterdam, The Netherlands.
Ricardo P J
RPJ
Budde
Department of Cardiology, Erasmus MC, Rotterdam, The Netherlands.
Jolien W
JW
Roos-Hesselink
Department of Radiology, Erasmus MC, Rotterdam, The Netherlands; Department of Cardiology, Erasmus MC, Rotterdam, The Netherlands.
Koen
K
Nieman
D000328:Adult; D001783:Blood Flow Velocity; D000067917:Cloud Computing; D003287:Contrast Media; D005260:Female; D005682:Gadolinium; D006330:Heart Defects, Congenital / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006801:Humans; D007089:Image Enhancement; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D011446:Prospective Studies; D011664:Pulmonary Valve / Q000000981:diagnostic imaging* / Q000503:physiopathology; D012680:Sensitivity and Specificity
D003287:Contrast Media; D005682:Gadolinium
4D CMR flow imaging; Eddy current correction; Flow visualization; Phase contrast; Pulmonary regurgitant fraction