INTRACRANIAL INFECTION AFTER MISSILE INJURIES TO THE BRAIN - REPORT OF 30 CASES FROM THE LEBANESE CONFLICT

This study reviews the features of 30 intracranial infections complicating 600 penetrating head injuries from missiles in patients treated at the American University of Beirut Medical Center between 1981 and 1988. The follow-up period ranged from 1 month to 7 years (mean, 2.5 years). Sixteen patients had a brain abscess, 9 had cerebritis, 2 had an infected intracerebral hematoma, and 5 had meningitis. Infection developed 4 days to 7 years after the initial debridement. The infecting organisms were Gram positive in 11 patients (36%), Gram negative in 12 (40%), and a combination of Gram positive and Gram negative in 2 (7%). Twenty-four patients (80%) had wound dehiscence or cerebrospinal fluid leakage at the time the infection appeared. There was a 76% correlation between the organisms cultured from the dehisced scalp wound and the brain. Twenty-three patients had intracranial retention of bone. Infection developed in 16 of the 30 patients (70%) around bone fragments, in 4 around a metallic fragment, in 2 around absorbable gelatin sponge, and in 3 along the missile tract; 2 had an infected intracerebral hematoma, and 3 had meningitis. At least one of the following risk factors was present in each patient: extensive brain injury, coma, trajectory through an air sinus, cerebrospinal fluid fistula, inadequate initial debridement, or incomplete dural closure. The incidence of intracranial infection in patients with postoperative retention of bone was 4% in the absence of scalp wound dehiscence, compared with 84.6% when wound dehiscence was present. Ten patients (43%) still retained a bone fragment measuring less than 1 cm after excision of a brain abscess or treatment of cerebritis or meningitis. None developed a recurrent infection. The authors conclude that a bone fragment measuring less than 1 cm that is retained after treatment of intracranial infection caused by a missile injury to the brain does not have to be removed when there is not wound dehiscence or leakage of cerebrospinal fluid.