Comparison of triamcinolone acetonide, 11-deoxycortisol and other lipid formulae for the visualization of vitreous body in the anterior chamber after posterior capsule rupture in animal models

The visualisation of vitreous using surface modified poly(lactic-co-glycolic acid) microparticles

AIMS To demonstrate the potential use of in vitro poly(lactic-co-glycolic acid) (PLGA) microparticles in comparison with triamcinolone suspension to aid visualisation of vitreous during anterior and posterior vitrectomy. METHODS PLGA microparticles (diameter 10-60 microm) were fabricated using single and/or double emulsion technique(s) and used untreated or following the surface adsorption of a protein (transglutaminase). Particle size, shape, morphology and surface topography were assessed using scanning electron microscopy (SEM) and compared with a standard triamcinolone suspension. The efficacy of these microparticles to enhance visualisation of vitreous against the triamcinolone suspension was assessed using an in vitro set-up exploiting porcine vitreous. RESULTS Unmodified PLGA microparticles failed to adequately adhere to porcine vitreous and were readily washed out by irrigation. In contrast, modified transglutaminase-coated PLGA microparticles demonstrated a significant improvement in adhesiveness and were comparable to a triamcinolone suspension in their ability to enhance the visualisation of vitreous. This adhesive behaviour also demonstrated selectivity by not binding to the corneal endothelium. CONCLUSION The use of transglutaminase-modified biodegradable PLGA microparticles represents a novel method of visualising vitreous and aiding vitrectomy. This method may provide a distinct alternative for the visualisation of vitreous whilst eliminating the pharmacological effects of triamcinolone acetonide suspension.

Experimental use of estriol for visualizing the vitreous body in the anterior chamber after posterior capsule rupture in animal models

PURPOSE

To compare the efficacy and safety of estriol and triamcinolone acetonide suspensions in visualizing the prolapsed vitreous body in the anterior chamber after posterior capsule rupture in animal models.

SETTING

Tsukuba University Institute of Clinical Medicine, Ibaraki, Japan.

METHODS

To evaluate efficacy, triamcinolone acetonide or estriol suspension was injected into the anterior chambers of porcine eyes after intentional posterior capsule rupture. To evaluate safety, triamcinolone acetonide 5.0 mg or estriol in 0.1 mL suspension was injected into the anterior chamber of New Zealand white rabbits. Slitlamp examinations, intraocular pressure (IOP), corneal endothelial cell density (ECD) measurements, and histologic examinations were performed up to 28 days after the injection.

RESULTS

Triamcinolone acetonide and estriol were equally effective in allowing visualization of the prolapsed vitreous body in the anterior chamber. The granules of triamcinolone acetonide or estriol disappeared 1 day after the injection and did not affect the IOP or corneal ECD. No statistically significant histological changes were observed in the eyes 28 days after the injection of triamcinolone acetonide or estriol.

CONCLUSIONS

Estriol was effective for the visualization of the prolapsed vitreous body in the anterior chamber after posterior capsule rupture. In experimental models, no significant side effects were observed after the injection of estriol in the anterior chamber. Results suggest that estriol is an alternative reagent for visualizing the vitreous body, especially in steroid responders, because it has no glucocorticoid or mineralocorticoid activity.