Patient with Chronic Headache, Unsteadiness and Frequent Falls

Patient with chronic headache, unsteadiness and frequent falls

A 73-year-old woman presented with chronic headache, occasional vomiting, unsteadiness and frequent falls. In the past few months there had been a progressive deterioration in her mental function and increasing drowsiness. Physical examination showed moderate papilloedema but was otherwise unremarkable. A CT brain was performed.

What is shown on the CT and what is the diagnosis ?