Subdural hematoma involving congenital arachnoid cyst
An elderly woman was noted to have a declining mental status,
mimicking dementia, over a period of several weeks. The patient was
physically feeble, but no focal neurologic signs or symptoms were
noted. Noncontrast computed tomography (CT) of the brain was
obtained (figure 1). Three findings on the CT were noted. An MR
scan was requested to clarify these findings (figure 2).