High-Resolution MR Cisternography of the Cerebellopontine Angle: 2D versus 3D Fast Spin-Echo Sequences
Eriko Iwayama
,a,
Shinji Naganawaa,
Tokiko Itoa,
Hiroshi Fukatsua,
Mitsuru Ikedaa,
Takeo Ishigakia and
Nobuyasu Ichinosea
a From the Department of Radiology, Nagoya University School of Medicine, Nagoya (E.I., S.N., T.It., H.F., M.I., T.Is.); and Toshiba Corporation, Tokyo (N.I.), Japan.
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FIG 1. Flow velocity and flow pattern of CSF in the prepontine cistern obtained in a volunteer with cine phase velocity mapping. The average peak velocity of CSF in four volunteers was 1.2 cm/s.
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FIG 2. A and B, Single-section 3-mm-thick 2D image (A) and 30-mm-slab 3-mm-section 3D image (B). The 2D image shows loss of signal intensity in the prepontine cistern (arrows) compared with the 3D image (arrows)
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FIG 3. A, Schematic diagram of 30-mm-slab 3D images (shaded area) with intraslab presaturation pulses except for the 1-mm-slab center volume.
B, 30-mm-slab 1-mm-section 3D image with intraslab presaturation pulses show signal loss (arrows).
C, Single-section 3-mm-thick 2D image shows some signal loss (arrowheads).
D, 30-mm-slab 1-mm-section 3D image without presaturation pulse shows no signal loss in the prepontine cistern.
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FIG 4. A–H, Comparison of various TEs in single-section 3-mm-thick 2D images: TE = 80 (A), TE = 100 (B), TE = 120 (C), TE = 160 (D), TE = 254 (E); and 30-mm-slab 1-mm-section 3D image (F). In all four volunteers, CSF signal relative to that of the water phantom decreased gradually as TE increased in single-section 3-mm-thick 2D images (G). In all four volunteers, CNR between the water phantom and the cerebellar peduncle increased gradually as TE increased (H)
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FIG 5. A–F, Comparison of various section thicknesses for single-section 2D images: 2 mm (A), 3 mm (B), 4 mm (C), 5 mm (D); and 30-mm-slab 1-mm-section 3D image (E). In all four volunteers, CSF signal relative to that of the water phantom increased gradually as section thickness increased (arrows in A–E) (F)
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FIG 6. Images obtained in a healthy volunteer for comparison of 2D and 3D FSE sequences.
A, Multisection 3-mm-thick 2D image.
B, 30-mm-slab 1-mm-section 3D image. The visibility of the vertebral artery is poor in the 2D image (arrow) but excellent in the 3D image (arrow).
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FIG 7. 57-year-old man with right-sided trigeminal neuralgia.
A and B, Multisection 3-mm-thick 2D image (A) and 30-mm-slab 1-mm-section 3D image (B). A mass (white arrowheads) presumed to be an epidermoid cyst compressing the trigeminal nerve (black arrowheads) is depicted in the right cerebellopontine angle. Although the tumor is isointense with CSF on the 3D image (large arrow), the tumor can be recognized more clearly on the 2D image, owing to signal loss in CSF (small arrows).
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