Abstract
Purpose: :
To investigate the feasibility of intra-choroidal implant, we examined the release of betamethasone phosphate (BP) from the intra-choroidal implant in rabbit eye.
Methods: :
The intra-choroidal implant was made of poly(DL-lactide) containing 50% BP( 0.15mg ). Under an operating microscope, a sclerotomy was made 6mm posterior to limbus. Choroid was exposed, and an incision was made. A spatula was then inserted into the intra-choroid through this opening and a cylindrical pocket was created. The implant prepared as above was inserted into a choroidal pocket in the rabbit’s eye. To determine how long the effect of implantation lasts, the concentration of BP in the choroid was measured by high-performance liquid chromatography (HPLC).
Results: :
Slit lamp examination showed no significant inflammatory reaction at the implantation sites at 4 weeks. Ophthalmoscopically, treated eyes were shown a whitish lesion, corresponding to the site of the BP-loaded implant. The BP concentration in choroid at 4 weeks after implantation was 7.4 ± 6.9 µg/ml ( n = 4, mean ± SD ). This confirmed that the level of BP in the choroid was effectively maintained for at least 4 weeks after intra-choroidal implantation.
Conclusions: :
The result suggests that this new intra-choroidal implantation technique can be used as a sustained intra-ocular drug delivery system.
Keywords: drug toxicity/drug effects • choroid