Objective:To investigate the safety and efficacy of intrav-itreal triamcinolone acetonide as t reatment for macular edema associated with central retin al vein occlusion(CRVO).Methods:We reviewed the medical re cords of13consecutive patients(13eyes)with macular edema as-sociated with CRVO who were treated w ith an injection of intravitreal triamcinolone aceton ide(4mg )at the Univer-sity of Wisconsin and the Bascom Palm er Eye Institute.Each intravitreal injection was delivered through the pars plana using a 27-or 30-gauge needle.Main Outcome Measures:Change in Snellen visual a cuity,clinical ap-pearance of macular edema,measurem ent of foveal thick-ening with optical coherence tomography(OCT),and fre-quency of complications.Results:T he median age of the 13patients was 67years(interquartile range,57-77years),and the median duration of symptoms before in-jection was 8months(interquartile range,4-9months).Mean baseline visual acuity was 20/500in the affected eye.Mean visual acuity at the 6-mont h follow-up exami-nation was 20/180in the affected eye.All 13patients completed the 6-month examination.Eyes with nonis-chemic CRVO(n =5)demonstrated a significant im-provement in visual acuity,whereas eyes with ischemic CRVO(n =8)demonstrated a nonsignificant visu al acuity improvement.No patient had a decrease in visual acuity.Mean baseline foveal thickness as me asured by OCT was590μm(retinal thickening =416μm).Mean foveal thickness as measured by OCT at the 1-month follow-up examination in 12patients was 212μm(retinal thicken-ing =38μm).At the 3-month follow-up examination,mean foveal thickness as measured by OCT for 13patients was 193μm(retinal thickening =19μm).Between the 3-and 6-month follow-up examinations,4patients developed a recurrence of macular edema.Three of the 4patients were retreated with a second injecti on of triamcinolone.Two of these 3patients experienced a n improvement in vi-sual acuity following retreatment.At the 6-month follow-up examination,mean foveal thickness as measured by OCT for13patients was 281μm(retinal thickening =107μm).No adverse effects such as retinal deta chment or endoph-thalmitis occurred.One patient exp erienced an increase in intraocular pressure that was contr olled with 2aqueous suppressants.Conclusions:Intravitreal injection of triam-cinolone appears to be a possibly effective treatment in some patients with macular edema associa ted with CRVO.Pa-tients with nonischemic CRVO may respond more favorably than patients with ischemic CRVO,an d retreatment may be necessary in some patients.In this c ase series,severe complications were not noted. Objective: To investigate the safety and efficacy of intrav-itreal triamcinolone acetonide as reatment for macular edema associated with central retinal vein occlusion (CRVO). Methods: We reviewed the medical re cords of 13concutive patients (13eyes) with macular edema as-sociated with CRVO who were treated w ith an injection of intravitreal triamcinolone aceton ide (4 mg) at the University of Wisconsin and the Bascom Palm er Eye Institute. Ech intravitreal injection was delivered through the pars plana using a 27-or 30-gauge needle . Main Outcome Measures: Change in Snellen visual a cuity, clinical ap-pearance of macular edema, measure of entance foveal thick-ening with optical coherence tomography (OCT), and fre quency of complications. Results: T he median age of the 13patients was 67years (interquartile range, 57-77years), and the median duration of symptoms before in-jection was 8months (interquartile range, 4-9months) .Mean baseline visual acuity was 20 / 500in the affected eye. Macro visual acuity at th e 6-mont h follow-up exami-nation was 20/180 in the affected eye. All 13 patients completed the 6-month examination. Eyes with non-chemic CRVO (n = 5) demonstrated significant im- provement in visual acuity, eyes with ischemic CRVO (n = 8) demonstrated a nonsignificant visu al acuity improvement. No patient had a decrease in visual acuity. Mean baseline foveal thickness as me asured by OCT was 590 μm (retinal thickening = 416 μm). Man foveal thickness as measured by OCT at the 1-month follow-up examination in 12 patients was 212 μm (retinal thickening = 38 μm) .A the 3-month follow-up examination, mean foveal thickness as measured by OCT for 13 patients was 193 μm (retinal thickening = 19 μm). Between the 3-and 6-month follow-up examinations, 4patients developed a recurrence of macular edema. Thhree of the 4patients were retreated with a second injecti on of triamcinolone. Two of these 3patients experienced an improvement in vi-sual acuity following retreatment. At the 6-month follow-up examination, me an fove adverse effects such as retinal detachment or endophthalmitis occurred. One patient exp erienced an increase in intraocular pressure that was contr olled with 2aqueous suppressants. Conclusions: Intravitreal injection of triam-cinolone appears to be a possibly effective treatment in some patients with macular edema associa ted with CRVO. Pa-tients with nonischemic CRVO may respond more favorably than patients with ischemic CRVO, an d retreatment may be necessary in some patients. this c ase series, severe complications were not noted.