Triamcinolone Acetonide

Triamcinolone acetonide is an antiinflammatory steroid that inhibits the IgE-dependent release of histamine. This is done by human basophils and the growth of NEL-M1 human melanoma cells.

A Prospective Randomized Trial of the Efficacy of Fibrin Glue, Triamcinolone Acetonide, and Quilting Sutures in Seroma Prevention after Latissimus Dorsi Breast Reconstruction.[Pubmed:28350654]

Plast Reconstr Surg. 2017 Apr;139(4):854e-863e.

BACKGROUND: Donor-site seroma is the most common complication following latissimus dorsi flap breast reconstruction. Various agents and techniques have attempted to minimize seroma formation. The purpose of this study was to compare the efficacy of different products and quilting sutures at seroma prevention. METHODS: This is a single-center, double-blinded, randomized, controlled trial of a consecutive series of breast cancer patients (n = 96) undergoing latissimus dorsi flap reconstruction performed by a single surgeon. Patients were randomized to receive (1) fibrin glue (Tisseel) (n = 23), (2) Triamcinolone Acetonide (n = 26), or (3) normal saline (control) (n = 27) sprayed into the donor site. The fourth arm included donor-site quilting sutures (n = 20). Outcomes included seroma, drain output, and days to last drain removal. Drain removal was standardized at less than 30 cc/day. RESULTS: All groups were matched evenly without differences in risk, procedures, or complications. The overall seroma rate was 31.3 percent (n = 30). The quilting group had significantly less drainage for weeks 1 (p = 0.006) and 2 (p = 0.050) postoperatively. Quilting statistically reduced the incidence of seromas to 5.0 percent (n = 1; p = 0.038) compared with other groups (control, 34.5 percent; fibrin, 27.6 percent; and triamcinolone, 37.6 percent). Drains were removed 10 days earlier with quilting (control, 35.5 days; fibrin, 39.5 days; triamcinolone, 37.4 days; and quilting, 25.8 days; p = 0.001). The incidence of all other complications was similar between groups. CONCLUSION: The use of quilting donor sites significantly decreases the incidence of donor-site seromas and leads to earlier drain removal following latissimus dorsi flap reconstruction and maintains a low complication profile. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, II.

Mechanisms of in vivo release of triamcinolone acetonide from PLGA microspheres.[Pubmed:28342981]

J Control Release. 2017 Jun 28;256:19-25.

Little is known about the underlying effects controlling in vitro-in vivo correlations (IVIVCs) for biodegradable controlled release microspheres. Most reports of IVIVCs that exist are empirical in nature, typically based on a mathematical relationship between in vitro and in vivo drug release, with the latter often estimated by deconvolution of pharmacokinetic data. In order to improve the ability of in vitro release tests to predict microsphere behavior in vivo and develop more meaningful IVIVCs, the in vivo release mechanisms need to be characterized. Here, two poly(lactic-co-glycolic acid) (PLGA) microsphere formulations encapsulating the model steroid Triamcinolone Acetonide (Tr-A) were implanted subcutaneously in rats by using a validated cage model, allowing for free fluid and cellular exchange and microsphere retrieval during release. Release kinetics, as well as mechanistic indicators of release such as hydrolysis and mass loss, was measured by direct analysis of the recovered microspheres. Release of Tr-A from both formulations was greatly accelerated in vivo compared to in vitro using agitated phosphate buffered saline +0.02% Tween 80 pH7.4, including rate of PLGA hydrolysis, mass loss and water uptake. Both microsphere formulations exhibited erosion-controlled release in vitro, indicated by similar polymer mass loss kinetics, but only one of the formulations (low molecular weight, free acid terminated) exhibited the same mechanism in vivo. The in vivo release of Tr-A from microspheres made of a higher molecular weight, ester end-capped PLGA displayed an osmotically induced/pore diffusion mechanism based on confocal micrographs of percolating pores in the polymer, not previously observed in vitro. This research indicates the need to fully understand the in vivo environment and how it causes drug release from biodegradable microspheres. This understanding can then be applied to develop in vitro release tests which better mimic this environment and cause drug release by the relevant mechanistic processes, ultimately leading to the development of mechanism based IVIVCs.

Vessel diameter study: intravitreal vs posterior subtenon triamcinolone acetonide injection for diabetic macular edema.[Pubmed:28338665]

Eye (Lond). 2017 Aug;31(8):1155-1162.

PurposeTo detect and compare the vessel diameter effect of intravitreal vs subtenon injection of triamcinolone for diabetic macular edema (DME).MethodsSixty patients with DME who underwent triamcinolone injection either intravitreally (N=30) or under the tenon capsule (N=30) were included. Non-injected fellow eyes served as control. The main outcome measures were central retinal artery equivalent (CRAE), central retinal vein equivalent (CRVE), and artery-vein ratio (AVR).ResultsIn the intravitreal group, pre-injection mean CRAE (147.07 mu) decreased to 141.03 mu at 1 week and to 139.43 mu at 1 month (P<0.001) while baseline CRVE (209.61 mu) decreased initially to 198.85 mu at 1 week then to 198.49 mu at 1 month (P<0.001). In the subtenon group, pre-injection CRAE (152.18 mu) decreased to 149.49 mu at 1 week and to 147.47 mu at 1 month (P=0.017), while baseline CRVE (215.60 mu) decreased initially to 208.69 mu at 1 week then to 207.25 mu at 1 month (P=0.003). Pre-injection AVR values did not change at 1 week and at 1 month in both injection groups (P=0.66 and P=0.196, respectively). In the control group, none of the 3 parameters changed throughout the study period compared to the baseline (P>0.28).ConclusionIn eyes with DME, both intravitreal and subtenon triamcinolone injection led to a significant constriction of retinal arteries and veins.