Vitrectomy in endophthalmitis. Results of study using vitrectomy, intraocular antibiotics, or a combination of both
A. J. Cottingham Jr and R. K. Forster
A rabbit model of endophthalmitis was produced by inoculating
Staphylococcus epidermidis and S aureus into the vitreous cavity.
Elimination of microorganisms was compared using intravitreal
administration of 0.1 mg of gentamicin alone, vitrectomy alone, and a
combination of gentamicin and vitrectomy. In the case of S. epidermidis
treated 24 hours after inoculation, all untreated eyes were
culture-positive at one week, eyes treated with gentamicin alone or
intravitreal gentamicin in combination with vitrectomy were all
culture-negative, and vitrectomy alone rendered half of the eyes
culture-negative. In the case of S aureus, eyes not treated by vitrectomy
alone were all culture-positive at one week. Eyes treated with intravitreal
gentamicin 25 to 31 hours after infection were culture-negative for S
aireus in 33% at one week, while eyes treated with combined vitrectomy plus
intraocular gentamicin were culture-negative in 83% of cases. When
treatment was delayed 40 to 49 hours after inoculation of S aureus,
intravitreal rendered 50% culture-negative at one week, while vitrectomy
combined with intravitreal gentamicin eliminated the infection in 100% of
eyes.
