Serial Neuroimaging of a Patient with Minor Stroke due to Isolated Cortical Vein Thrombosis and Convexal Subarachnoid Hemorrhage.

PURPOSE Convexal subarachnoid hemorrhage (cSAH) comprises less than 5% of cases of nontraumatic SAH and frequently presents as a focal and transient neurological deficits that mimics transient ischemic attack (TIA). Isolated cortical vein thrombosis (ICVT) is rare and accounts for only 6.3% of cerebral venous thrombosis. We present a case of minor stroke due to cSAH secondary to ICVT, and alos put emphasis on the chronological change of those serial imagings. CASE REPORT An 87-year-old man presented with episodes of numbness and dropping of his left arm, which had lasted for three days. Brain computed tomography disclosed a cSAH in the right frontoparietal region. Brain magnetic resonance (MR) study showed a cSAH in the right fronto-parietal sulci. Focal swelling of the right frontal cortex with an intraluminal filling defect in the right cortical vein and venous congestion were observed using post-contrast T1-weighted images, suggesting partial thrombosis with recanalization of the cortical vein but a patent superior sagittal sinus. Diffuse linear superficial cortical hemosiderosis (SCH) was detected in the right anterior frontal cortex, right fronto-parietal cortex and left high frontal cortex. He spontaneously recovered from his minor neurological deficits within two weeks. A follow-up MR study three weeks later found a hyperintense cord sign indicating a cSAH in the right high central sulcus on fluid-attenuated inversion recovery and T2-weighted images. A further follow-up MR study two months later showed gradual shrinkage of the cSAH with persistent diffuse SCH. CONCLUSION This case report clearly showed chronological change of brain MRI and head CT findings. MR studies help in recognizing the occurrence of acute and chronic cSAHs, and ICVT.