Focal angiographic abnormalities with subdural empyema.

Thirteen patients with subdural empyema underwent arteriography preoperatively and three were restudied postoperatively. Arterial vascular changes were found in nine cases and consisted of localized or diffuse arterial irregularities. In two cases the arterial changes resolved with effective therapy. These arterial changes are similar in appearance and response to therapy to those noted with meningitis; however, in this series they were shown to have occured in seven cases with subdural empyema but without associated meningitis. Therefore, empyema alone may cause localized or diffuse arterial irregularities.