case_images: PMC9082262_01
case_images: Neuroradiological data from onset to day 4. (A, B) CT images before and after intravenous thrombolysis showed no abnormalities except punctate hyperdensities within the left frontal sulci (red arrows). (C, D) CT angiography on day 4 showed filling defects of cortical veins (red arrows) and compensatory expansion of the adjacent veins (green arrows). (E, F) MRI on day 3 showed hyperintense T1WI and FLAIR lesions neighboring the falx cerebri and the left parietal cortex (red arrows), which were initially diagnosed as subarachnoid hemorrhages, indicating subacute thrombosis in the cortical veins. (G) MRI on day 4 showed venous infarction in the frontal lobe (green arrow) and the absence of the flowing-void effect in the cortical veins (red arrows). (H) Susceptibility-weighted imaging on day 4 showed curvilinear, serpentine, and exaggerated susceptibility within the sulcus, which was suggestive of thrombosed veins during the acute (red arrows) and subacute phases (greed arrow).
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case_images: PMC9082262_01_fimmu-13-882032-g001.jpg
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case_images: National Institute of Health stroke scale (NIHSS) score at admission was 2. Non-contrast computed tomography (NCCT) was performed, and the radiologist reported no acute abnormalities ( Figure 1A ). A repeat CT at 24 h showed no hemorrhage ( Figure 1B ). The brain MRI on day 3 revealed punctate abnormalities [hyperintensity on T1-weighted imaging (T1WI) and fluid-attenuated inversion recovery imaging (FLAIR)] that neighbored the cerebral falx and left frontal sulcus ( Figures 1E, F  ). However, filling defects of CoVs and compensatory expansion of the adjacent veins were present ( Figures 1C, D ). The MRI on the night of day 4 showed a venous infarction in the frontal lobe ( Figure 1G ). Susceptibility-weighted imaging (SWI) showed curvilinear, serpentine-exaggerated susceptibility within the sulcus, which indicated thrombosed veins in the acute phase ( Figure 1H ).
case_images: Neuroradiological data after day 4. (A, B) CT images on days 6 and 10 showed progressive enlargement of the venous infarction lesion in the frontoparietal cortex (red arrows). (C) MRI on day 12 showed venous infarction lesions with a large acute hematoma in the left frontoparietal lobe, which resulted in transtentorial herniation (red arrows). (D) CT scan after decompression craniectomy showed large areas of low-density lesions (red arrow). (E) MR black-blood-thrombus imaging (MRBTI) on day 7 showed vein thrombosis that extended proximally to the superior sagittal sinus (red arrow). The superior sagittal sinus was free of thrombosis (green arrow). (F) MR venography showed filling defects of the left frontal and partial cortical veins (red arrows). (G, H) DSA on day 8 showed normal venous flow of the right hemisphere (G, green arrow) compared with multiple thromboses in the left superior and internal cerebral veins of the left hemisphere (H, red arrows).
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case_images: An enlargement in the venous infarction was observed on the re-examination CT ( Figure 2A ). MR black-blood-thrombus imaging (MRBTI) on day 7 showed vein thrombosis that extended proximally to the superior sagittal sinus ( Figure 2E ). MR venography showed filling defects of the left frontal and partial cortical veins ( Figure 2F ). The conditions continued to worsen progressively, with enlargement of the venous infarction in the CT on day 10 ( Figure 2B ). On day 12, the patient progressed to a coma, and the MRI showed a large intracranial hemorrhage (ICH) in the left frontoparietal lobe and transtentorial herniation ( Figure 2C ). Decompressive craniectomy was performed immediately ( Figure 2D ).
case_images: Timeline of the present case.
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case_images: PMC9082262_01_fimmu-13-882032-g003.jpg
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case_images: The timeline of the case is showed in the  Figure 3 .