 There has been interval expected evolution of sequela of hypoxic ischemic injury, with essentially severe cystic degeneration of the majority of the brain parenchyma bilaterally with sparing of the posterior fossa and brainstem. The basal ganglia, caudate, and thalami are relatively preserved, with scant scattered cerebral hemispheric tissue elsewhere, predominantly along the ventricular margins and the diminutive occipital as well as temporal lobes.There has been interval increased size of the left holohemispheric subdural collection, with with its contents demonstrating prominent T1 hyperintensity to gray matter and conspicuous T2 hyperintensity greater than CSF. This now measures up to 14 mm in greatest thickness, with flattening of the subjacent cystic appearing tissue. There appears to be a septation deep within this collection. Linear intrinsic T1 hyperintensity with diffusion restriction and susceptibility remain along this septation along the surface of the encephalomalacic tissue, likely relating to chronic blood products. Scattered punctate foci susceptibility remaining along the left greater than right frontal convexity likely relate to sequela of previous subarachnoid blood products.In the right frontal extra-axial space, there is also increased prominence of the now 8 mm thick collection which is also T1 hyperintense to gray matter, although remaining essentially isointense to gray matter on T2-weighted imaging. There is also mass effect from this smaller collection upon the right frontal tissue. These are consistent with evolving blood products. Is significant ex vacuo dilatation of the lateral and third ventricles.Intracranial flow-voids associated with the circle of Willis are diminutive in size likely relating to the extensive tissue loss.
1.Interval expected evolution of previous sequelae of hypoxic ischemic injury, with essentially near complete cystic and cephalization of the cerebral hemispheres with relative sparing of the deep gray nuclei and portions of the temporal and occipital lobes.2.Conspicuous increased size of left much greater than right subdural collections containing blood products with mild mass effect.3.Minimal susceptibility remaining from previous scattered convexity subarachnoid hemorrhage.4.Associated ex vacuo dilatation of the lateral and third ventricles.