Presurgical Evaluation of the Motor Hand Area with Functional MR Imaging in Patients with Tumors and Dysplastic Lesions
Eric Achten, MD, PhD2,1,
Graeme D. Jackson, MD, PhD1,4,
Julie A. Cameron, MD2,
David F. Abbott, PhD1,
Damien L. Stella, MD2 and
Gavin C. A. Fabinyi, MD3
1 Brain Imaging Research Institute (E.A., G.D.J., D.F.A.)
2 Departments of Radiology (J.A.C., D.L.S.)
3 Neurosurgery (G.C.A.F.)
4 Neurology (G.D.J.), Austin and Repatriation Medical Centre, Studley Rd, Heidelberg 3084, Victoria, Australia.
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Figure 1a. Localizing the sections for functional MR imaging. (a) Coronal T1-weighted localizer MR image (300/15). (b–d) Three oblique T1-weighted localizer images (300/15) from which (b) superficial to (d) deep oblique sections for functional MR imaging were selected. b–d were acquired parallel to the line from the superior sagittal sinus to the sylvian fissure at the approximate level of the central sulcus (16). Note that the central sulcus (arrowheads) and the motor HRA (arrow) can easily be seen in b–d.
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Figure 1b. Localizing the sections for functional MR imaging. (a) Coronal T1-weighted localizer MR image (300/15). (b–d) Three oblique T1-weighted localizer images (300/15) from which (b) superficial to (d) deep oblique sections for functional MR imaging were selected. b–d were acquired parallel to the line from the superior sagittal sinus to the sylvian fissure at the approximate level of the central sulcus (16). Note that the central sulcus (arrowheads) and the motor HRA (arrow) can easily be seen in b–d.
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Figure 1c. Localizing the sections for functional MR imaging. (a) Coronal T1-weighted localizer MR image (300/15). (b–d) Three oblique T1-weighted localizer images (300/15) from which (b) superficial to (d) deep oblique sections for functional MR imaging were selected. b–d were acquired parallel to the line from the superior sagittal sinus to the sylvian fissure at the approximate level of the central sulcus (16). Note that the central sulcus (arrowheads) and the motor HRA (arrow) can easily be seen in b–d.
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Figure 1d. Localizing the sections for functional MR imaging. (a) Coronal T1-weighted localizer MR image (300/15). (b–d) Three oblique T1-weighted localizer images (300/15) from which (b) superficial to (d) deep oblique sections for functional MR imaging were selected. b–d were acquired parallel to the line from the superior sagittal sinus to the sylvian fissure at the approximate level of the central sulcus (16). Note that the central sulcus (arrowheads) and the motor HRA (arrow) can easily be seen in b–d.
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Figure 2a. Stack displays used to detect motion. The abscissa of the stack images is the pixel values of a predefined row (XZ) and corresponding column (YZ) selected interactively by putting a crosshair on any image in the functional MR imaging time series. The ordinate is the same pixel row and/or column from all the images in the time series. (a) Stack for the control subject in whom the images in Figure 3 were obtained. No movement was present; in the Z direction of the stack (ordinate), no wobbling or shift of lines is visible. (b) Stack for patient 3 shows wobbling and shifts (arrows) in the Z direction, an indication of unacceptable motion.
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Figure 2b. Stack displays used to detect motion. The abscissa of the stack images is the pixel values of a predefined row (XZ) and corresponding column (YZ) selected interactively by putting a crosshair on any image in the functional MR imaging time series. The ordinate is the same pixel row and/or column from all the images in the time series. (a) Stack for the control subject in whom the images in Figure 3 were obtained. No movement was present; in the Z direction of the stack (ordinate), no wobbling or shift of lines is visible. (b) Stack for patient 3 shows wobbling and shifts (arrows) in the Z direction, an indication of unacceptable motion.
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Figure 3a. Typical results of the analysis: difference maps and t-test maps. (a–c) T1-weighted axial oblique localizer images (300/15) obtained in a control subject overlaid with color-coded and thresholded (difference > 2%) difference maps at three consecutive levels from superficial to deep. (d–f) T1-weighted axial oblique localizer images (300/15) overlaid with color-coded and thresholded (t > 2.75) t-test maps. Typical artifacts in a–c are the important edge phenomena due to CSF pulsation (solid arrows) and the more prominent spurious covariance of unrelated pixels (arrowheads). Note the omega-shaped (open arrow in a–f) motor HRA, with an excellent depiction of the same in e. Three sections were sufficient to include all the activated pixels in the HRA.
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Figure 3b. Typical results of the analysis: difference maps and t-test maps. (a–c) T1-weighted axial oblique localizer images (300/15) obtained in a control subject overlaid with color-coded and thresholded (difference > 2%) difference maps at three consecutive levels from superficial to deep. (d–f) T1-weighted axial oblique localizer images (300/15) overlaid with color-coded and thresholded (t > 2.75) t-test maps. Typical artifacts in a–c are the important edge phenomena due to CSF pulsation (solid arrows) and the more prominent spurious covariance of unrelated pixels (arrowheads). Note the omega-shaped (open arrow in a–f) motor HRA, with an excellent depiction of the same in e. Three sections were sufficient to include all the activated pixels in the HRA.
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Figure 3c. Typical results of the analysis: difference maps and t-test maps. (a–c) T1-weighted axial oblique localizer images (300/15) obtained in a control subject overlaid with color-coded and thresholded (difference > 2%) difference maps at three consecutive levels from superficial to deep. (d–f) T1-weighted axial oblique localizer images (300/15) overlaid with color-coded and thresholded (t > 2.75) t-test maps. Typical artifacts in a–c are the important edge phenomena due to CSF pulsation (solid arrows) and the more prominent spurious covariance of unrelated pixels (arrowheads). Note the omega-shaped (open arrow in a–f) motor HRA, with an excellent depiction of the same in e. Three sections were sufficient to include all the activated pixels in the HRA.
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Figure 3d. Typical results of the analysis: difference maps and t-test maps. (a–c) T1-weighted axial oblique localizer images (300/15) obtained in a control subject overlaid with color-coded and thresholded (difference > 2%) difference maps at three consecutive levels from superficial to deep. (d–f) T1-weighted axial oblique localizer images (300/15) overlaid with color-coded and thresholded (t > 2.75) t-test maps. Typical artifacts in a–c are the important edge phenomena due to CSF pulsation (solid arrows) and the more prominent spurious covariance of unrelated pixels (arrowheads). Note the omega-shaped (open arrow in a–f) motor HRA, with an excellent depiction of the same in e. Three sections were sufficient to include all the activated pixels in the HRA.
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Figure 3e. Typical results of the analysis: difference maps and t-test maps. (a–c) T1-weighted axial oblique localizer images (300/15) obtained in a control subject overlaid with color-coded and thresholded (difference > 2%) difference maps at three consecutive levels from superficial to deep. (d–f) T1-weighted axial oblique localizer images (300/15) overlaid with color-coded and thresholded (t > 2.75) t-test maps. Typical artifacts in a–c are the important edge phenomena due to CSF pulsation (solid arrows) and the more prominent spurious covariance of unrelated pixels (arrowheads). Note the omega-shaped (open arrow in a–f) motor HRA, with an excellent depiction of the same in e. Three sections were sufficient to include all the activated pixels in the HRA.
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Figure 3f. Typical results of the analysis: difference maps and t-test maps. (a–c) T1-weighted axial oblique localizer images (300/15) obtained in a control subject overlaid with color-coded and thresholded (difference > 2%) difference maps at three consecutive levels from superficial to deep. (d–f) T1-weighted axial oblique localizer images (300/15) overlaid with color-coded and thresholded (t > 2.75) t-test maps. Typical artifacts in a–c are the important edge phenomena due to CSF pulsation (solid arrows) and the more prominent spurious covariance of unrelated pixels (arrowheads). Note the omega-shaped (open arrow in a–f) motor HRA, with an excellent depiction of the same in e. Three sections were sufficient to include all the activated pixels in the HRA.
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Figure 4a. Patient 4. Displacement of the central sulcus by a tumor adjacent to the precentral gyrus in the right hemisphere. (a) T1-weighted axial image (13/15) shows that the central sulcus and the adjoining cortex (arrow) are stretched and slightly displaced. (b–d) T1-weighted axial images (300/15) show that the activation of the HRA (arrow) is stretched as well but is present in the expected area. The proximity of the tumor to the eloquent cortex was confirmed with Penfield stimulation. Superficial to deep levels are shown in b–d. Only biopsy was performed; the lesion was classified as astrocytoma grade II.
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Figure 4b. Patient 4. Displacement of the central sulcus by a tumor adjacent to the precentral gyrus in the right hemisphere. (a) T1-weighted axial image (13/15) shows that the central sulcus and the adjoining cortex (arrow) are stretched and slightly displaced. (b–d) T1-weighted axial images (300/15) show that the activation of the HRA (arrow) is stretched as well but is present in the expected area. The proximity of the tumor to the eloquent cortex was confirmed with Penfield stimulation. Superficial to deep levels are shown in b–d. Only biopsy was performed; the lesion was classified as astrocytoma grade II.
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Figure 4c. Patient 4. Displacement of the central sulcus by a tumor adjacent to the precentral gyrus in the right hemisphere. (a) T1-weighted axial image (13/15) shows that the central sulcus and the adjoining cortex (arrow) are stretched and slightly displaced. (b–d) T1-weighted axial images (300/15) show that the activation of the HRA (arrow) is stretched as well but is present in the expected area. The proximity of the tumor to the eloquent cortex was confirmed with Penfield stimulation. Superficial to deep levels are shown in b–d. Only biopsy was performed; the lesion was classified as astrocytoma grade II.
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Figure 4d. Patient 4. Displacement of the central sulcus by a tumor adjacent to the precentral gyrus in the right hemisphere. (a) T1-weighted axial image (13/15) shows that the central sulcus and the adjoining cortex (arrow) are stretched and slightly displaced. (b–d) T1-weighted axial images (300/15) show that the activation of the HRA (arrow) is stretched as well but is present in the expected area. The proximity of the tumor to the eloquent cortex was confirmed with Penfield stimulation. Superficial to deep levels are shown in b–d. Only biopsy was performed; the lesion was classified as astrocytoma grade II.
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Figure 5a. Patient 5. Alteration of the HRA by a dysplastic lesion in a patient with intractable epilepsy. (a) T2-weighted axial (3,287/90) and (b) T1-weighted coronal (3,150/27/300 [repetition time msec/echo time msec/inversion time msec]) images clearly show a dysplastic lesion (arrow) in the right frontal lobe. The central sulcus is deformed and difficult to identify. (c, d) Functional MR images (600/15; 40° flip angle) show motor activation (solid arrow) at two locations in the border of the lesion. Activation of the sensory cortex (open arrow in d) at the level of the hand and activation in the posterior parietal cortex (Brodmann areas 5 and 7) were prominent. These activations were confirmed by means of Penfield stimulation.
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Figure 5b. Patient 5. Alteration of the HRA by a dysplastic lesion in a patient with intractable epilepsy. (a) T2-weighted axial (3,287/90) and (b) T1-weighted coronal (3,150/27/300 [repetition time msec/echo time msec/inversion time msec]) images clearly show a dysplastic lesion (arrow) in the right frontal lobe. The central sulcus is deformed and difficult to identify. (c, d) Functional MR images (600/15; 40° flip angle) show motor activation (solid arrow) at two locations in the border of the lesion. Activation of the sensory cortex (open arrow in d) at the level of the hand and activation in the posterior parietal cortex (Brodmann areas 5 and 7) were prominent. These activations were confirmed by means of Penfield stimulation.
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Figure 5c. Patient 5. Alteration of the HRA by a dysplastic lesion in a patient with intractable epilepsy. (a) T2-weighted axial (3,287/90) and (b) T1-weighted coronal (3,150/27/300 [repetition time msec/echo time msec/inversion time msec]) images clearly show a dysplastic lesion (arrow) in the right frontal lobe. The central sulcus is deformed and difficult to identify. (c, d) Functional MR images (600/15; 40° flip angle) show motor activation (solid arrow) at two locations in the border of the lesion. Activation of the sensory cortex (open arrow in d) at the level of the hand and activation in the posterior parietal cortex (Brodmann areas 5 and 7) were prominent. These activations were confirmed by means of Penfield stimulation.
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Figure 5d. Patient 5. Alteration of the HRA by a dysplastic lesion in a patient with intractable epilepsy. (a) T2-weighted axial (3,287/90) and (b) T1-weighted coronal (3,150/27/300 [repetition time msec/echo time msec/inversion time msec]) images clearly show a dysplastic lesion (arrow) in the right frontal lobe. The central sulcus is deformed and difficult to identify. (c, d) Functional MR images (600/15; 40° flip angle) show motor activation (solid arrow) at two locations in the border of the lesion. Activation of the sensory cortex (open arrow in d) at the level of the hand and activation in the posterior parietal cortex (Brodmann areas 5 and 7) were prominent. These activations were confirmed by means of Penfield stimulation.
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Copyright © 1999 by the Radiological Society of North America.
