Penetration of cephaloridine into the subretinal fluid.

Abstract

Cephaloridine is a wide-spectrum antibiotic derived from cephalosporin and, despite similarities to penicillin, it can be used in the treament of infections in penicillin-sensitive patients. Riley, Boyle, and Leopold (I968) and Records (I969) have reported the intraocular penetration of cephaloridine into the aqueous after intramuscular and intravenous administration, and Moll, Crawford, and McPherson (197i) have shown penetration into the subretinal fluid after subconjunctival injection, but penetration ofantibiotic into the subretinal fluid after systemic administration has not hitherto been reported.McMeel (I965), Criswick and Brockhurst (i969), and Lincoff, Nadel, and O'Connor (I970) have described infection after retinal detachment surgery. Langston, Lincoff, and McLean (I965) showed that a purulent endophthalmnitis may be produced experimentally with external plombage and diathermy without drainage of subretinal fluid and, although cryotherapy has largely replaced diathermy, the drainage site of subretinal fluid provides a potential route for the entry of organisms into the eye.In the management of endophthalmitis after retinal detachment surgery, it is not always simple to distinguish between the clinical signs of anterior segment ischaemia (Crock, I967), a sterile endophthalmitis, and endophthalmitis due to bacterial infection.Before diagnosis can be established, the systemic administration of an antibiotic may be indicated.In attempting to select antibiotics for the treatment of intraocular infection after detachment surgery, it would be valuable to know what levels of antibiotic are reached in subretinal fluid after systemic administration.The purpose of this paper is to report the penetration of cephaloridine into subretinal fluid in patients with retinal detachment after intramuscular injection.Material and methods 2I patients undergoing routine retinal detachment surgery were studied. In no case were local or systemic antibiotics administered during the week preceding operation. At varying times before surgery (if to 2* hrs), i g. cephaloridine, dissolved in 22-5 ml. sterile water, was injected intramuscularly into the gluteal region. In twelve patients IO ml. blood were taken before the injection of cephaloridine. IO ml. venous blood were taken at the time of subretinal fluid collection in all but three cases. Subretinal fluid was obtained by incising the sclera and then partly cauterizing the underlying choroid until the subretinal space was entered. Before puncture of the choroid, the site was carefully dried and haemostasis of the surrounding tissue was secured to avoid contamination of the specimen. A small receptacle (Figure) was held under the puncture wound and subretinal fluid was collected. The fluid was immediately transferred to the laboratory in vacuum flasks