Chronic subdural haematoma preceded by persistent traumatic subdural fluid collection.

The role of traumatic subdural fluid collections in the development of chronic subdural haematomas was studied in 43 of 715 patients who underwent a CT scan because of a recent head injury. Twenty of the 43 patients subsequently developed a chronic subdural haematoma, and this occurred especially in the aged. Nearly 50% of patients with asymptomatic or minimally symptomatic subdural fluid collection may develop a chronic subdural haematoma.