Intravitreal Penetration of Penicillin and Penicillin Therapy of Infections of the Vitreous

Recently von Sallmann, Meyer and Di Grandi¹have pointed out the unsatisfactory response of ectogenous infections of the vitreous to any type of therapy. Von Sallmann²demonstrated that iontophoresis with penicillin and iontophoresis plus systemic administration of sulfonamide compounds failed to produce improvement of ectogenous intraocular infections. Because these authors were unable to produce adequate levels of penicillin in the vitreous of the normal eye by corneal iontophoresis or by systemic administration, they resorted to direct intravitreal injections. Their studies showed that penicillin was present in the vitreous humor in a concentration greater than the bacteriostatic requirement for twenty-four hours after the initial injection. Initial intravitreal injections of penicillin produced retinal damage at the site of the needle puncture and opacities and occasional hemorrhage in the vitreous. The authors stated that if a fine needle was used and directed into the central area of the vitreous there was