Methylprednisolone therapy for retinal laser injury

Objective: Laser photocoagulation treatment of the posterior pole of the re tina is often complicated by immediate visual impairment, which is caused b y the unavoidable laser-induced destruction of the normal tissue adjacent t o the lesion. A neuroprotective therapy aimed at salvaging this normal tiss ue might enhance the benefit obtained from treatment and permit safe perifo veal photocoagulation. To determine whether corticosteroids can provide neu roprotection during photocoagulation, we examined the effect of methylpredn isolone on laser-induced retinal injury in a rat model. Methods: Argon lase r lesions were inflicted on the retinas of 36 rats and were followed immedi ately by intraperitoneal injections of high-dose methylprednisolone or sali ne. The animals were sacrificed after 3, 20, or 60 days, and their retinal lesions were evaluated histologically and morphometrically. Results: No his topathologic differences were observed between the treated and control anim als. Methylprednisolone treatment was demonstrated to posses some neuroprot ective effect for a short time after laser exposure, but was ineffective in ameliorating the long-term results of retinal laser injury. Conclusions: O n the basis of our results, we suggest that high-dose methylprednisolone tr eatment is ineffective in ameliorating laser-induced retinal injury. Other drugs should be investigated for their potential role as neuroprotective ag ents to prevent the spread of retinal laser damage. (Surv Ophthalmol 44 [Su ppl 1]:S85-S92, 1999. (C) 1999 by Elsevier Science Inc. All rights reserved .).