HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Abstract Full Text Full Text (PDF) Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Quigley, M. F. Articles by Haughton, V. Search for Related Content PubMed PubMed Citation Articles by Quigley, M. F. Articles by Haughton, V.

Cerebrospinal Fluid Flow in Foramen Magnum: Temporal and Spatial Patterns at MR Imaging in Volunteers and in Patients with Chiari I Malformation¹

¹ From the Departments of Radiology and Medical Physics, University of Wisconsin, 600 Highland Ave, Madison WI 53792. Received May 12, 2003; revision requested July 2; revision received October 10; accepted November 17. Address correspondence to V.H. (e-mail: vmhaughton@wisc.edu).

View larger version (87K): [in a new window]   Figure 1. Fourteen successive transverse phase-contrast MR images (flip angle, 20°; 20/5; section thickness, 5 mm; field of view, 180 mm; matrix, 256 x 256; encoding velocity, 10 cm/sec) of CSF flow through foramen magnum during cardiac cycle in a volunteer. CSF velocities are color coded, with a violet-blue-green-yellow-orange-red scale corresponding to a range from –3.0 cm/sec (caudad velocities) to 3.0 cm/sec (cephalad velocities). The subarachnoid space is outlined in white lines. Flow is cephalad (diastole) in 1-3, caudad (systole) in 6-11, not going in either direction in 12, and cephalad again in 13 and 14. Symmetrical regions or nodes in the anterolateral subarachnoid space have the greatest cephalad and caudad velocities. Vertebral arteries are identified as predominantly violet regions outside the subarachnoid space at the extreme right and left of the field of view. In the image plane, blood flow within these arteries exhibits a negative (caudad) component, resulting in the violet coloration of the arterial regions. Some arterial aliasing, evidenced by small red regions corresponding to apparent positive flow, is seen in both arteries.

View larger version (34K): [in a new window]   Figure 2. Surface contour plots of velocity data in Figure 1 (transverse phase-contrast MR images through foramen magnum of presumably healthy adult). The flow is scaled from –3.0 to 3.0 cm/sec, as indicated by the color-velocity scale on the left. Velocities outside the region of CSF flow have been set equal to 0 to aid in visualization. Surfaces above the horizon plane show cephalad flow (in 1-3, 13, and 14), and surfaces below the horizon plane show caudad flow (in 6-12). The contour plots show the spatial inhomogeneity of flow, with higher cephalad velocities within the anterior nodes. They show slightly greater cephalad and caudad velocities in the anterior subarachnoid space than in the posterior subarachnoid space. The difference is more pronounced for cephalad velocities. At the phases in the cardiac cycle that correspond to transitions between cephalad and caudad flow (in 4, 5, and 12), little flow is present in either direction.

View larger version (82K): [in a new window]   Figure 3. Fourteen successive transverse phase-contrast MR images of CSF flow through foramen magnum during cardiac cycle in patient with symptomatic Chiari I malformation. Color coding and imaging parameters are same as in Figure 1. The subarachnoid space is outlined in white lines. 1-5 show cephalad CSF flow; 6-11, caudad CSF flow; and 13 and 14, cephalad flow again. At the transition from caudal to cephalad flow (in 12), little flow is evident. Color images show pronounced flow inhomogeneity. Regions of the anterior paramidline subarachnoid space have markedly elevated velocities. The posterior subarachnoid space, compared with the anterior subarachnoid space, has reduced velocities. 1-5 show CSF flow in both the cephalad direction (paramidline) and the caudad direction (midline).

View larger version (41K): [in a new window]   Figure 4. Surface contour plots of velocity data in Figure 3 (transverse phase-contrast MR images through foramen magnum of symptomatic patient with Chiari I malformation). The flow is scaled from –3.0 to 3.0 cm/sec. Velocities outside the region of CSF flow have been set to 0. 1-3 show a large cephalad jet in right anterior subarachnoid space and an even larger one in left anterior subarachnoid space. Somewhat smaller caudad jets are evident in 7-11. Bidirectional flow is less conspicuous in the surface contour plots because of the orientation of the image plane.

View larger version (56K): [in a new window]   Figure 5. Phase-contrast MR image and two alternate views of surface contour plot (3 in Figs 3 and 4, respectively) in patient with Chiari I malformation show regions with cephalad (red) and caudad (violet) flow in different regions in the subarachnoid space. The subarachnoid space is outlined in white lines on the MR image. The surface contour plots have been oriented to display the bidirectional flow more effectively. Extreme cephalad velocities are seen in the two anterior jets, and extreme caudad velocities are seen in counterjets adjacent to the anterior jets.

View larger version (82K): [in a new window]   Figure 6a. (a) Transverse phase-contrast MR image of cumulative flow in each voxel at end of cardiac cycle (color coding, –0.5 to 0.5 cm/sec; subarachnoid space outlined in white lines), (b) graph of velocity for each voxel as function of time, and (c) graph of cumulative flow for each voxel as function of time in volunteer. In a, the cumulative flow is shown in a violet-blue-green-yellow-orange-red color scale from –0.5 to 0.5 mm3. In b, the units of measure for velocity are millimeters per second, and in c, the units for cumulative flow are cubic millimeters. A series of voxels are highlighted in white and green in a, and the time courses for these voxels are indicated with the same colors in b and c. In b and c, the mean velocity and mean cumulative flow are shown as heavy white traces. Cumulative flow is seen to fall within a range of about –2 to 2 mm3 in individual voxels (a, c). Voxels exhibiting extreme CSF velocities (white and green traces in b) show some of the largest positive or negative cumulative flow at the end of the cardiac cycle (a, c).

View larger version (22K): [in a new window]   Figure 6b. (a) Transverse phase-contrast MR image of cumulative flow in each voxel at end of cardiac cycle (color coding, –0.5 to 0.5 cm/sec; subarachnoid space outlined in white lines), (b) graph of velocity for each voxel as function of time, and (c) graph of cumulative flow for each voxel as function of time in volunteer. In a, the cumulative flow is shown in a violet-blue-green-yellow-orange-red color scale from –0.5 to 0.5 mm3. In b, the units of measure for velocity are millimeters per second, and in c, the units for cumulative flow are cubic millimeters. A series of voxels are highlighted in white and green in a, and the time courses for these voxels are indicated with the same colors in b and c. In b and c, the mean velocity and mean cumulative flow are shown as heavy white traces. Cumulative flow is seen to fall within a range of about –2 to 2 mm3 in individual voxels (a, c). Voxels exhibiting extreme CSF velocities (white and green traces in b) show some of the largest positive or negative cumulative flow at the end of the cardiac cycle (a, c).

View larger version (25K): [in a new window]   Figure 6c. (a) Transverse phase-contrast MR image of cumulative flow in each voxel at end of cardiac cycle (color coding, –0.5 to 0.5 cm/sec; subarachnoid space outlined in white lines), (b) graph of velocity for each voxel as function of time, and (c) graph of cumulative flow for each voxel as function of time in volunteer. In a, the cumulative flow is shown in a violet-blue-green-yellow-orange-red color scale from –0.5 to 0.5 mm3. In b, the units of measure for velocity are millimeters per second, and in c, the units for cumulative flow are cubic millimeters. A series of voxels are highlighted in white and green in a, and the time courses for these voxels are indicated with the same colors in b and c. In b and c, the mean velocity and mean cumulative flow are shown as heavy white traces. Cumulative flow is seen to fall within a range of about –2 to 2 mm3 in individual voxels (a, c). Voxels exhibiting extreme CSF velocities (white and green traces in b) show some of the largest positive or negative cumulative flow at the end of the cardiac cycle (a, c).

View larger version (71K): [in a new window]   Figure 7a. (a) Transverse phase-contrast MR image of cumulative flow in each voxel at end of cardiac cycle (color coding, –0.5 to 0.5 mm/sec; subarachnoid space outlined in white lines), (b) graph of velocity for each voxel as function of time, and (c) graph of cumulative flow for each voxel as function of time in patient with Chiari I malformation. In a, the cumulative flow is shown in a violet-blue-green-yellow-orange-red color scale from –0.5 to 0.5 mm3. In b, the units of measure for velocity are millimeters per second, and in c, the units for cumulative flow are cubic millimeters. A series of voxels are highlighted in white and green in a, and the time courses for these voxels are indicated with the same colors in b and c. In b and c, the mean velocity and cumulative flow are shown as heavy white traces. Cumulative negative (caudad) flow of up to 4 mm3 at the end of the cardiac cycle is seen in some voxels (a, c). In adjacent regions, cumulative positive (cephalad) flow in the posterior region is near 0, less than 0.25 mm3. Voxels with positive cumulative flow at the end of the cardiac cycle (white traces in c) exhibit cephalad velocities in excess of 40 mm/sec. Voxels with negative cumulative flow at the end of the cardiac cycle (green traces in c) exhibit caudad velocities of 20-50 mm/sec. In most voxels, cephalad velocities are less than 30 mm/sec.

View larger version (34K): [in a new window]   Figure 7b. (a) Transverse phase-contrast MR image of cumulative flow in each voxel at end of cardiac cycle (color coding, –0.5 to 0.5 mm/sec; subarachnoid space outlined in white lines), (b) graph of velocity for each voxel as function of time, and (c) graph of cumulative flow for each voxel as function of time in patient with Chiari I malformation. In a, the cumulative flow is shown in a violet-blue-green-yellow-orange-red color scale from –0.5 to 0.5 mm3. In b, the units of measure for velocity are millimeters per second, and in c, the units for cumulative flow are cubic millimeters. A series of voxels are highlighted in white and green in a, and the time courses for these voxels are indicated with the same colors in b and c. In b and c, the mean velocity and cumulative flow are shown as heavy white traces. Cumulative negative (caudad) flow of up to 4 mm3 at the end of the cardiac cycle is seen in some voxels (a, c). In adjacent regions, cumulative positive (cephalad) flow in the posterior region is near 0, less than 0.25 mm3. Voxels with positive cumulative flow at the end of the cardiac cycle (white traces in c) exhibit cephalad velocities in excess of 40 mm/sec. Voxels with negative cumulative flow at the end of the cardiac cycle (green traces in c) exhibit caudad velocities of 20-50 mm/sec. In most voxels, cephalad velocities are less than 30 mm/sec.

View larger version (49K): [in a new window]   Figure 7c. (a) Transverse phase-contrast MR image of cumulative flow in each voxel at end of cardiac cycle (color coding, –0.5 to 0.5 mm/sec; subarachnoid space outlined in white lines), (b) graph of velocity for each voxel as function of time, and (c) graph of cumulative flow for each voxel as function of time in patient with Chiari I malformation. In a, the cumulative flow is shown in a violet-blue-green-yellow-orange-red color scale from –0.5 to 0.5 mm3. In b, the units of measure for velocity are millimeters per second, and in c, the units for cumulative flow are cubic millimeters. A series of voxels are highlighted in white and green in a, and the time courses for these voxels are indicated with the same colors in b and c. In b and c, the mean velocity and cumulative flow are shown as heavy white traces. Cumulative negative (caudad) flow of up to 4 mm3 at the end of the cardiac cycle is seen in some voxels (a, c). In adjacent regions, cumulative positive (cephalad) flow in the posterior region is near 0, less than 0.25 mm3. Voxels with positive cumulative flow at the end of the cardiac cycle (white traces in c) exhibit cephalad velocities in excess of 40 mm/sec. Voxels with negative cumulative flow at the end of the cardiac cycle (green traces in c) exhibit caudad velocities of 20-50 mm/sec. In most voxels, cephalad velocities are less than 30 mm/sec.