Fluid-Attenuated Inversion-Recovery MR Imaging in Acute and Subacute Cerebral Intraventricular Hemorrhage
Rohit Bakshi
,a,
Sadaat Kamrana,
Peter R. Kinkela,
Vernice E. Batesa,
Laszlo L. Mechtlera,
Vallabh Janardhana,
Shaleen L. Belania and
William R. Kinkela
a From the Dent Neurologic Institute, Lucy Dent Imaging Center, Kaleida Health System, Millard Fillmore Hospital, State University of NY, Buffalo, NY.
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FIG 1. Case 12: 70-year-old man with subacute aneurysmal IVH and SAH who had MR imaging 9 days after ictus and CT 8 days after ictus. The FLAIR images show each occurrence of hemorrhage more conspicuously than do the CT scans. Although both FLAIR MR imaging and CT depicted IVH, the FLAIR images more crisply show the fluid-fluid levels characteristic of IVH.
A and B, FLAIR images (6700/150/2, TI = 2200) show layered IVH in the trigones of the lateral ventricles, which are hyperintense (A), resulting in blood-CSF fluid-fluid levels. Mixed intensities in the third ventricle are most likely caused by CSF pulsation artifact (and were also seen on the control images). Hyperintense posterior bilateral parietal and occipital (A) and right rolandic (B) cortical sulci represent SAH.
C and D, Noncontrast CT scans show both the IVH and SAH less conspicuously than do the FLAIR images, including layered IVH (C), bilateral parietooccipital SAH (C), and right rolandic sulcus SAH (D).
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FIG 2. Case 7: 24-year-old man with acute IVH and intraparenchymal hemorrhage who had MR imaging and CT 12 hours apart, each approximately 72 hours after ictus. Although the IVH is more easily seen on the CT scans than on the FLAIR images, the T1-weighted images show the IVH as well as the CT scans do.
A, FLAIR image (6700/150/2, TI = 2200) shows a marked hypointensity, consistent with clot, in the posterior aspect of the right lateral ventricle. The linear meniscus (arrow) demarcates the posterior clot from the normal anterior CSF signal. The marked hypointensity of the IVH is most likely caused by the T2 shortening effects of intracellular methemoglobin present abundantly in the clot at this IVH stage. The hypointensity of this state of blood breakdown resembles normal dark CSF. In addition, heterogeneous signal is present in the mesial part of the right parietooccipital lobe with surrounding hyperintensity, consistent with an AVM. (Focal hyperintensity in the left lateral ventricle is most likely caused by a CSF pulsation artifact, which was also seen on control images.)
B and C, Clotted IVH is markedly hyperintense and easily seen on T1-weighted image (450/20/2) (B). The IVH is markedly hypointense on T2-weighted image (2000/120/2) (C). The T1- and T2-weighted imaging appearances are consistent with the predominantly intracellular methemoglobin content of the IVH.
D, Noncontrast CT scan shows calcified AVM and clotted IVH, each hyperdense.
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FIG 3. Case 2: 79-year-old woman with acute IVH, intraparenchymal hemorrhage, and SAH who had imaging on the day of ictus. MR and CT studies were obtained 2 hours apart. The FLAIR images show the IVH and SAH better than the T1- and T2-weighted images or the CT scans do.
A–C, FLAIR images (6700/150/2, TI = 2200) show large left parietooccipital intraparenchymal hemorrhage with intraventricular extension and associated SAH. The intraparenchymal hemorrhage is of mixed signal (mostly isointense). However, the IVH is well seen as hyperintense in the right occipital horn (arrow, A) and left body (arrow, B) of the lateral ventricles. SAH is well seen as hyperintensities in the right dorsal frontoparietal sulci (B and C).
D–I, T1-weighted (450/20/2) (D–F) and T2-weighted (2000/120/2) (G–I) images do not show the IVH and SAH as conspicuously as the FLAIR images do.
J–L, Noncontrast CT scans readily show the hyperdense intraparenchymal hemorrhage. However, the IVH and SAH are shown more conspicuously on the FLAIR images.
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FIG 4. Case 9: 82-year-old woman with subacute IVH and intraparenchymal hemorrhage who had imaging 5 days after ictus. MR images and a CT scan were obtained 2 hours apart. The CT scan shows the IVH better than the MR images do.
A and B, Layered IVH is isointense with gray matter on all three MR sequences and is thus inconspicuous on the FLAIR image (6700/150/2, TI = 2200) (A), the T2-weighted image (2000/120/2) (B), and the T1-weighted image (450/20/2) (not shown).
C, Noncontrast CT scan readily shows the hyperdense intraparenchymal hemorrhage and hyperdense ipsilateral layered IVH. The IVH is more conspicuous on the CT scans than on the MR images.
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