Purpose:To study the effect of intravitreal injections of triamcinolone acetonide (TA) for the treatment of macular edema secondary to central retinal vein occlusion (CRVO)in a sample of Chinese patients from Shaanxi province.Methods:The 50 eyes from 50 patients were separated into three TA treatment groups:17 patients were given 4 mg/0.1ml,19 patients were given 8 mg/0.2 ml,and 14 patients were given 16 mg/0.4 ml.Patients were followed up for 12 months.Foveal thickness,intraocular pressure (IOP),and best-corrected visual acuity (BCVA) were measured.Results:Macular edema responded well both anatomically and functionally to the TA injections.After the initial intravitreal injection,macular edema recurred at 2-4 months in the low-dose group (4 mg),at 3-5 months in the medium-dose group (8 mg),and at 6-9 months in the high-dose group (16 mg).No significant difference in BCVA or in foveal thickness were observed between the first intravitreal injection and the re-injection.There was no increase in IOP after re-injection of 16 mg TA,if the patient did not have an elevated IOP after the initial intravitreal injection of 4/8 mg TA.Conclusion:A low dosage of TA (4 mg) administered via intravitreal injection might be useful as an initial treatment for macular edema secondary to CRVO.A higher dosage of TA (16mg) can be used if there is no IOP elevation with the initial TA injection.