Safety of intravitreal ketorolac and diclofenac: an electroretinographic and histopathologic study.
OBJECTIVE
To determine the clinical, histologic, and electroretinographic effects in the rabbit retina of escalating doses of two intravitreally delivered nonsteroidal anti-inflammatory drugs (NSAIDs): ketorolac and diclofenac.


METHODS
Right eyes received a single 0.1 mL injection of either ketorolac (500-6000 microg/0.1 mL) or diclofenac (300-1500 microg/0.1 mL) prepared in balanced salt solution (BSS). Left eyes served as controls and received BSS. Dark- and light-adapted electroretinograms (ERG) were obtained at baseline and 4 and 8 weeks postinjection. Enucleated eyes were examined histologically.


RESULTS
Ophthalmic examinations demonstrated no signs of intraocular inflammation or retinal toxicity. Intraocular pressure measurements remained similar between NSAID injected and control eyes. Histologic and ERG studies of eyes injected with 6000 microg ketorolac and >or=500 microg diclofenac demonstrated toxicity. In contrast, doses up to 3000 microg ketorolac demonstrated enhanced b-wave amplitude responses. Delayed drug toxicity was observed for the highest doses of both NSAIDs.


CONCLUSIONS
Intravitreal 3000 microg ketorolac and 300 microg diclofenac were nontoxic in this animal study, and may offer an effective and safer alternative to intravitreal corticosteroids.
Kim
Stephen J
SJ
Department of Ophthalmology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA. skim30@gmail.com
Adams
Neal A
NA
Toma
Hassanain S
HS
Belair
Marie-Lyne
ML
Thorne
Jennifer E
JE
Green
W Richard
WR
Jabs
Douglas A
DA
D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000633:toxicity*; D003623:Dark Adaptation; D004008:Diclofenac / Q000633:toxicity*; D004596:Electroretinography / Q000187:drug effects*; D007267:Injections; D007429:Intraocular Pressure / Q000187:drug effects; D020910:Ketorolac / Q000633:toxicity*; D011817:Rabbits; D012160:Retina / Q000187:drug effects* / Q000473:pathology; D014822:Vitreous Body
D000894:Anti-Inflammatory Agents, Non-Steroidal; D004008:Diclofenac; D020910:Ketorolac