SUBDURAL ABSCESS
The subdural abscesses (mentioned also as “empyema”) usually occupy large areas on the convexity and basal surface of the brain hemispheres. The origin of the infection is frequently in the paranasal sinuses or the middle ear. It can be also a complication after any craniotomy.
Headache, fever, neck rigidity, and focal epileptic attacks are the early signs and symptoms. Many of the patients with a subdural abscess deteriorate suddenly with rapid impairment of the level of consciousness and focal neurological deficit. The resulting mortality is high. CT and MRI are essential for early and precise diagnosis.
The surgical treatment consists of a craniotomy, evacuation of the pus and removal of the granulation tissue. The cavity is washed with saline and antibiotics and the wound is closed with a fine subdural drainage line left inside. Antibiotic instillation into the cavity may be required.
Urgent surgical treatment in these cases is the rule. The removal of the extensive granulation tissue and multiple abscesses needs wider craniotomies and many burr holes. Drainage tubes are inserted in a way that permits washing of all the cavities with antibiotics. CT follow-up control is essential and antibiotic therapy is continued for 3 weeks after clinical signs have completely subsided. Any source of infection in the sinuses is treated aggressively and simultaneously with the subdural empyema.