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PROPELLER Acquisition on the Philips Achieva Recent results collected in Hamburg – JAN 2006
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Philips Medical Systems, E. Brian Welch, Hamburg Results JAN 20062 Recent TSE results collected in Hamburg – JAN 2006 Liquid-filled resolution phantom experiencing high-speed in-plane rotational motion induced by a computer controlled stepper motor TSE, readout matrix size = 384, 25 blades over 180°, blade width=24 STATIC MOTION UNCORRECTED MOTION CORRECTED
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Philips Medical Systems, E. Brian Welch, Hamburg Results JAN 20063 The plot is periodic like the actual phantom motion Detected angles are large leading to large missing “wedges” in k-space TSE, readout matrix size = 384, 25 blades over 180°, blade width = 24 Detected Angular Motion k-space after motion correction Recent TSE results collected in Hamburg – JAN 2006
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Philips Medical Systems, E. Brian Welch, Hamburg Results JAN 20064 Simple short TR gradient echo acquisition – not known to be published nor presented to dateSimple short TR gradient echo acquisition – not known to be published nor presented to date FFE, readout matrix size=256, 34 blades over 360°, blade width=24, blade acquisition duration ~=150 msecFFE, readout matrix size=256, 34 blades over 360°, blade width=24, blade acquisition duration ~=150 msec STATIC MOTION UNCORRECTED MOTION CORRECTED Recent FFE results collected in Hamburg – JAN 2006
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Philips Medical Systems, E. Brian Welch, Hamburg Results JAN 20065 Amplitude and speed of motion phantom is smaller than in TSE experiment Because of increased number of propeller blades collected over 360°, no wedges of k-space are missing even after correction for rotation FFE, readout matrix size=256, 34 blades over 360°, blade width=24, blade acquisition duration ~= 150 msec Recent FFE results collected in Hamburg – JAN 2006 Detected Angular Motion k-space after motion correction
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Philips Medical Systems, E. Brian Welch, Hamburg Results JAN 20066 Animation loops showing the low resolution “disk images” collected by every FFE propeller bladeAnimation loops showing the low resolution “disk images” collected by every FFE propeller blade Rotation is noticeable in uncorrected disk images… corrected disk images are stableRotation is noticeable in uncorrected disk images… corrected disk images are stable STATIC MOTION UNCORRECTED MOTION CORRECTED Recent FFE results collected in Hamburg – JAN 2006
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Philips Medical Systems, E. Brian Welch, Hamburg Results JAN 20067 Center of Mass criterion is not useful on FFE data TSE center of mass is smoothly sinusoidal (LEFT GRAPH) FFE susceptibility inconsistencies as readout direction changes with blade orientation create a distorted center of mass trajectory (RIGHT GRAPH) Recent TSE + FFE results collected in Hamburg – JAN 2006 STATIC TSE STATIC FFE
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