Purchase this article with an account.
Masatoshi Murata, Atushi Sanbe; Retro-ocular insertion of intrachoroidal dexamethasone implant for drug delivery system to posterior eye segment. Invest. Ophthalmol. Vis. Sci. 2017;58(8):4449.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Dexamethasone(DEX) is widely used for the treatment of posterior segment eye diseases. However, it is difficult to deliver effective doses of DEX to the posterior eye segment for long periods. We have generated a simple procedure of retro-ocular implantation through sclera for the intrachoroidal DEX delivery. This procedure would be helpful to increase the DEX level in the posterior retina.
An implant was prepared by dissolving poly(DL-lactide) and DEX. In vitro release of DEX was measured at 1, 7, and 21 days by ELISA. In vivo, 25G needle was shallowly stabbed the sclera and moved ahead in the choroid. After that, the implant in 25G needle, was inserted to the choroid by using an injector at 2 disc diameter inferior to the optic disc. After the implantation, the DEX level in the retina was determined at 1, 7, and 21 days by mass spectrometry. Possible adverse effects of the implant, were evaluated by ophthalmoscopy and light microscopy. Endotoxn-induced uveitis (EIU) was induced after DEX implantation, and anti-inflammatory activities were evaluated by histopathologic studies.
The implant showed an initial burst within 24 hours, and then the DEX was gradually released at least for 3 weeks in vitro. In vivo, the intrachoroidal implant at 24 hours effectively delivered the DEX into the posterior retina. After that, this implant released the DEX constantly at least for 3 weeks. DEX implant showed no retinal abnormalities except the implantation site in ophthalmoscopy and light microscopy. The implant effectively prevented the retinal inflammation in EIU.
We have demonstrated a simple methodology of retro-ocular implantation through sclera for intrachoroidal sustained drug delivery system in posterior eye segment. This new drug delivery system may be useful in adjusting the most effective and minimum medication to individual patient. Furthermore, this procedure might be possible to insert a tube instead of the DEX implant.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.
This PDF is available to Subscribers Only