<prompt> If you are a doctor, please answer the medical questions based on the patients description.What does the following MRI of the brain report mean? There is a small chronic lacunar infarct versus a dilated perivascular space in the posterior left centrum semiolale. A small chronic lacunar infarct in the left thalamus is observed. There is no evidence of restricted diffusion to suggest acute infarction in the brain parenchyma. There is a mildly prominent CSF overlying the cerebral hemispheres secondary to moderate generalized cerebral and cerebellar volume loss rathat than subdural hygromas. The ventricles and basilar cisterns are normal in size.  <response>: Lacuna infarction are ischemic brain lesions less than 1 cm in diameter. The first one described is not sure to be an infarction as it can also be a dilated perivascular space, witch can be a variation of normal anatomy or changes through a persons life. I dont understand well the sentence before the last, but I suppose its a brain atrophy caused by an old subdural hemorrhage. You should see a neurologist to value the risk factors for cerebral vascular disease and to treat the patient properly. 