Brain abscess. There is a heterogeneous cystic lesion in the left parietal lobe that measures up to approximately 20 mm. There is extensive surrounding vasogenic edema. A previously demonstrated subcentimeter lesion in the left temporal stem is barely discernible due to the lack of intravenous contrast. There is a background of diffuse cerebral white matter T2 hyperintensity. There is unchanged marked prominence of the ventricles, particularly the third and lateral ventricles. There is no significant midline shift or herniation. Skin fiducial markers are present.
1. Preoperative planning MRI for a left parietal lobe abscess with extensive vasogenic edema. Assessment of the previously demonstrated left temporal stem lesion is otherwise limited due to the lack of intravenous contrast.2. Unchanged ventriculomegaly, which may represent a normal pressure hydrocephalus superimposed upon cerebral volume loss, 3. Unchanged nonspecific background of diffuse cerebral white matter abnormality.