Abstract
Purpose: :
To characterize the in vitro behavior of 3 preparations of triamcinolone acetonide.
Methods: :
Three preparations of triamcinolone acetonide were mixed with Balanced Salt Solution Plus (BSS Plus): commercially available triamcinolone acetonide (TA), compounded preservative-free triamcinolone acetonide (PFTA), and triamcinolone acetonide injectable suspension (TAIS). We determined mean number of crystalline aggregates per high power deconvolution microscopy field, largest aggregate area, and spectroscopic photometric absorption (SPA).
Results: :
PFTA had larger mean number of aggregates compared to TA (time zero p=0.002, 10 minutes p<0.001) and TAIS (time zero p<0.001, 10 minutes p=0.003). Aggregate size varied at both 0 and 10 minutes: TAIS > TA > PFTA. SPA decreased in direct correlation to aggregate size over time for all 3 preparations.
Conclusions: :
PFTA in BSS Plus has more aggregates of smaller size than TA and TAIS. TAIS has much larger aggregate size than PFTA and TA, and increases over time. These findings correlate with the observation that TA tends to spread more evenly throughout the vitreous and epiretinal membrane and internal limiting membrane, and TAIS lacks diffuse distribution, instead gravitating toward the most dependent portion of the eye in a globular fashion.
Keywords: vitreoretinal surgery • injection • vitreous