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FIG 1. MR images of a 59-year-old woman with a hemorrhagic spinal subdural metastasis.
A, T2-weighted fast spin-echo image in the sagittal plane shows a mass (arrows) in the spinal canal that is of higher signal intensity in its central portion with peripheral hypointensity. The lesion is extramedullary and extends behind the C3 and C4 vertebral bodies, almost completely filling the spinal canal.
B, T2*-weighted midsagittal gradient-echo image shows that the mass (arrows), which has a broad base anteriorly, consistent with extramedullary origin, is predominantly hypointense, indicative of a blood clot.
C, T2*-weighted gradient-echo image in the axial plane at the C4-C5 level shows a mass (arrows) arising in the left anterior subdural space, extending into the left lateral recess, and causing severe spinal cord compression. The lesion is of mixed low and high signal intensity, indicative of partially clotted acute hemorrhage. The compressed spinal cord is hyperintense (arrowhead).
D, T2*-weighted gradient-echo image at the C3-C4 level reveals at least 2 focal areas of very low signal intensity (arrows) within the spinal cord, corresponding to hemorrhagic cord lesions.
E, Precontrast T1-weighted sagittal spin-echo image corresponding to A shows a lack of visualization of cerebrospinal fluid around the spinal cord at the C4 and C5 levels, indicating that the mass is isointense with the cord. The signal intensity pattern of this lesion is consistent with a combination of oxyhemoglobin (bright on T2-weighted images) with deoxyhemoglobin and early clot formation (dark areas on T2- and especially T2*-weighted images), corresponding to hyperacute-to-acute hemorrhage.
F, Postcontrast T1-weighted sagittal spin-echo image corresponding to E demonstrates an absence of lesion enhancement. Note the presence of contrast enhancement in the anterior epidural space at the C1-C2 level and in the pharyngeal mucosa.
G, Postcontrast axial T1-weighted spin-echo image corresponding to C shows a lack of lesion enhancement. The image is from the delayed set of postcontrast T1-weighted images acquired after postcontrast scanning of the brain. The absence of enhancement may be due to the mass effect of the hemorrhage and a relatively isolated location of the lesion. Contrast enhancement could perhaps have been observed with a higher (triple) dose of contrast agent.
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