Brain Imaging in the Unsedated Pediatric Patient: Comparison of Periodically Rotated Overlapping Parallel Lines with Enhanced Reconstruction and Single-Shot Fast Spin-Echo Sequences
Kirsten P. Forbesa,
James G. Pipea,
John P. Karisa,
Victoria Farthinga and
Joseph E. Heisermana
a From the Barrow Neurological Institute, Phoenix, AZ
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FIG 1. Illustration of PROP k-space data acquisition. Data are acquired in a series of rotating blades, each of which collects data from the central area of k-space. Each blade contains several phase-encode lines.
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FIG 2. Bar graph shows the mean score of the two observers in grading both PROP and SS-FSE images for visible effects of motion. Scores were as follows: 0, no motion; 1, mild motion; 2, moderate motion; and 3, severe motion. On most images, no motion effects were seen, and PROP and SS-FSE performed equally in terms of motion correction.
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FIG 3. Compensation of moderate head motion with SS-FSE and PROP FSE imaging.
A, T1-weighted image shows the effects of head motion. Motion artifact and variable signal intensity are demonstrated across the image.
B, SS-FSE image shows no evidence of motion artifact and enables a good assessment of ventricular size.
C, PROP FSE image offers improved gray matter-white matter differentiation. Note that artifact overlying the right side of the skull. This was caused by a ventricular catheter and was worse on this study than on others because of a higher receiver bandwidth.
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FIG 4. Compensation of severe head motion with SS-FSE and PROP FSE imaging.
A, T1-weighted image shows the effects of severe head motion, with notable motion artifact and image blurring.
B, SS-FSE image shows a marked reduction in motion artifact, although the artifact remains even when a parent is holding the child’s head still.
C, PROP FSE image also offers a substantial reduction in motion artifact, although the image still demonstrates some blurring.
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FIG 5. Visibility of pathology on SS-FSE and PROP images. Bar graph shows the impressions of the two observers regarding the images that depicted pathology most clearly. While observer 1 judged most of the images to be equal, observer 2 thought that PROP images offered an advantage.
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FIG 6. Bar graph reveals the sequences that the observers preferred. Both observers clearly preferred PROP images because of improvements in the contrast of the brain parenchyma.
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FIG 7. Improved image contrast with PROP MR imaging.
A, SS-FSE image of the brain allows assessment of ventricular size and subarachnoid spaces, but assessment of the brain parenchyma is limited.
B, PROP FSE image offers improved contrast, which allows a more-detailed assessment of both gray matter and white matter. This improvement allows the identification of a small focus of gray matter heterotopia in the lateral wall of the right lateral ventricle.
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AJNR - American Journal of Neuroradiology