Purpose: We studied events leading to the development of posttraumatic endophthalmitis by examining the significance of 15 factors on microbial contamination of injured eyes.
Methods: A prospective study was done of 30 ruptured globes in patients admitted to an urban medical center. Cultures were taken from the conjunctiva before and after preoperative disinfection and from the anterior chamber at the beginning and end of wound repair. Twenty-five of 30 patients received a three-day regimen of intravenous antibiotics that were begun before surgery.
Results: Anterior chamber samples grew microorganisms in ten (33%) of 30 eyes, with positive cultures recovered from specimens taken at the beginning of wound repair in eight eyes and at the end of wound repair in six eyes. Contamination with indigenous flora may have occurred at the time of injury in one eye and during repair in another eye. Microbes recovered included Staphylococcus, Corynebacterium, and Aspergillus species. No patient developed endophthalmitis. Of the 15 factors studied, only intravenous antibiotics significantly decreased the incidence of positive anterior chamber cultures in eyes treated before wound repair compared with eyes not receiving such therapy (P = .002).
Conclusions: Despite the frequency of anterior chamber microbial contamination during injury or repair of the wound, with our treatment protocol and the presence of physiologic mechanisms to reduce intraocular microbes, no eyes developed clinical endophthalmitis. With our limited sample size only intravenous antibiotic therapy was found significantly to reduce anterior chamber microorganisms at the time of surgical repair, supporting their prophylactic use against the development of posttraumatic endophthalmitis.