Status epilepticus. Acute subdural hematoma. Rule out vascular abnormality.Additional history from EMR: Concern for possible nonaccidental trauma. BRAIN MRI:There is a relatively thin T1-hyperintense, T2-hypointense subacute appearing subdural hemorrhage overlying the posterior cerebral (right parietal and occipital and left occipital) and cerebellar convexities, that is most pronounced in the right occipital region with a maximum thickness of 7 mm, compared to 5 mm on previous CT scan. The subdural hematoma is also involving the fixed edges of the cerebral falx and cerebellar tentorium, reaching close to the superior lip of the left porus acoustics. Overall distribution of the subdural hematoma has not significantly changed from the previous CT scan and mild mass-effect on the underlying brain remains minimal. In addition, there is a near CSF intensity more chronic appearing subdural collection that overlies the left cerebral convexity near the vertex, which has a maximum thickness of 5 mm. It is mildly FLAIR hyperintense. This is unchanged and only minimally displaces the underlying brain parenchyma.The large area of parenchymal hypoattenuation in the posterior aspect of the right cerebral hemisphere on CT correlates with relatively mild diffusion restriction and mild gray- and white-matter edema with partial loss of gray-white-matter differentiation. There is also mild asymmetric sulcal effacement in these areas. This involves the right parietal lobe and part of the right temporal and occipital lobes, as well as the posterolateral right thalamus. There is questioned focal mild gyriform diffusion restriction involving the left occipital and parietal lobes as well. These are also conspicuous diffusion restriction involving the splenium of the corpus callosum and also extending along the right corticospinal tract into the posterior limb of the internal capsule and cerebral peduncle, likely reflecting acute Wallerian degeneration. There is no intraparenchymal or subarachnoid hemorrhage. There is a prominent vessel along right occipital lobe which seems to join the vein of Galen (1201/47). This is associated with an adjacent area of mildly confluent hypervascularity on the contrast enhanced MR angiogram neck images in the right occipital lobe (3001/23). It is also associated with prominent vein of Galen on MR venography along with poor visualization and apparent slight irregularity of the anterior aspect of the straight sinus on both planes of MRV acquired. The ventricles are normal in size. There is no midline shift or herniation. There is no gross orbital abnormality. The posterior pituitary bright spot is preserved.CRANIAL MRA:Accounting for the limitation caused by the small patient size, there is no significant stenosis or aneurysm of the major intracranial arteries. Flow related signal is increased in the parietal branches of the right middle cerebral artery and the right posterior cerebral artery and its branches. There is also hypervascularity on the contrast enhanced MR angiogram in the right occipital lobe which correlates with the prominent vessels described above on conventional and susceptibility weighted imaging brain sequences. It is also associated with prominent vein of Galen on MR venography along with poor visualization of the anterior aspect of the straight sinus. CRANIAL MRV:The superior sagittal, transverse and sigmoid sinuses are patent. As described above, the vein of Galan is prominent while the anterior aspect of the straight sinus is poorly visualized. This prominent vein of Galen is associated with the prominent vessels in the right occipital lobe described above. The internal cerebral veins and the posterior part of the straight sinus are patent. The included upper parts of the internal jugular veins are patent as well. NECK MRA:The study is further limited by patient motion which most significantly affects the lower part of the right vertebral artery on the time-of-flight imaging. Within the limitation of the pre and postcontrast examinations, there is no occlusion or severe stenosis of the major cervical arteries. The aortic arch branching pattern is conventional.
1.Thin supratentorial and infratentorial probably subacute subdural hematomas, with minimal mass-effect on the underlying brain. Additional larger left cerebral convexity more chronic appearing subdural hematoma.2.Mild diffusion restriction involving the right parietal as well as portions of the right temporal and occipital lobes in addition to the right dorsolateral thalamus, with smaller areas questioned in the left parietal and occipital lobes. Findings are of uncertain etiology given the nonterritorial distribution, involving portions of the posterior MCA as well as PCA territory. While the appearance may reflect pseudonormalization in the subacute phase of recent acute ischemia, the unusual distribution raises the possibility of venous congestion/ischemia as well as underlying transient seizure-related signal change given patient's history of status epilepticus. 3.Asymmetrically prominent right occipital region vessel likely a vein may represent incidental developmental venous anomaly. Also, suggestion of asymmetric mildly confluent faint enhancement of the right occipital parenchyma in the area adjacent to this prominent vessel, which could potentially relate to venous congestion secondary to suboptimal venous drainage in the area of potential DVA in an area of underlying seizure activity. However, the associated poor visualization of the anterior segment of the straight sinus along with a mildly prominent vein of Galen immediately proximal make it difficult to exclude an underlying vascular malformation or abnormality. High-resolution, 3-D MR imaging of the brain with contrast may provide more details about these findings. In addition, CT angiogram or conventional cerebral angiogram can also be considered.4.The associated diffusion restriction along the right corticospinal fibers and corpus callosal splenium is probably related to acute Wallerian degeneration.5.There is no gross intracranial arterial abnormality. There is suggestion of mild hypervascularity in the parietal right middle cerebral artery branches and the right posterior cerebral artery and its branches, probably reactive to ischemia or seizure activity, and possibly compressive due to mild residual cerebral edema.6.There is no gross neck arterial abnormality.