Intraocular availability of triamcinolone acetonide after intravitreal injection

To evaluate the intraocular concentration of triamcinolone acetonide after intravitreal injection.

The prospective clinical interventional case series study included 17 patients who had received a 20 to 25-mg intravitreal injection of triamcinolone acetonide as treatment for exudative age-related macular degeneration, diffuse diabetic macular edema, or retinal vein occlusions. During a secondary intraocular surgery taking place 4.1 weeks to 25.7 months after the intravitreal injection, aqueous humor samples were obtained. None of the eyes were vitrectomized.

In the aqueous humor samples, triamcinolone acetonide was in low, but measurable, concentrations detected up to 1.5 years after the intravitreal injection. Concentrations found in samples obtained during the first 6 months, or 7 to 12 months, respectively, after the injection ranged between 3.0 microg/l and 436 microg/l, and between 0.0 microg/l and 11.2 microg/l, respectively.

After injection of triamcinolone acetonide, triamcinolone can be present in measurable concentrations up to 1.5 years after the application.