Purchase this article with an account.
S. Patel, H. F. Edelhuaser, J. M. Nickerson, M. R. Prausnitz; Suprachoroidal Drug Delivery Using Microneedles. Invest. Ophthalmol. Vis. Sci. 2008;49(13):5006.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Currently practiced ocular drug delivery methods, such as topical application, systemic administration and intravitreal injection, are either inefficient or invasive for posterior segment delivery. Microneedles have the potential to provide a minimally invasive, targeted method of drug delivery to the suprachoroidal space. In this work, we examine (1) whether microneedles can selectively deliver particles to the suprachoroidal space, and (2) the pressures and (3) insertion depth required for suprachoroidal delivery. The particles in the suprachoroidal space can provide sustained delivery directly to the choroid and retina for diseases that affect the posterior of the eye.
Hollow glass microneedles were used to infuse nano- and micro-particle suspensions into the suprachoroidal space by inserting across the sclera. Experiments were performed on whole rabbit, pig, and human eyes in-vitro. Delivery was verified visually, as well as using florescence microscopy using whole eyes and histological cross sections.
Microneedles were shown to deliver nano- and micro-particle suspensions into the suprachoroidal space of rabbit, pig, and human eyes. Particle diameters used include 20 nm, 100 nm, 500 nm, and 1 µm. The particles can be designed to provide controlled drug delivery from the suprachoroidal space. Volumes of 15-30 µL were delivered into the space using a single microneedle; volumes delivered to rabbit eyes were lower compared to pig and human which were similar. Pressures required for delivery ranged from 150 kPa to 300 kPa with a small dependence on particle size. Insertion depth for suprachoroidal delivery was 500-700 µm in rabbit and 700-1000 µm in pig and human.
Microneedles have shown for the first time to deliver nano- and micro- particle suspensions into the suprachoroidal space of rabbit, pig and human eyes. As a result, microneedles may provide a minimally invasive way for controlled drug delivery to the posterior of the eye, thus reducing dosing frequency and also allowing for better therapeutic control.
This PDF is available to Subscribers Only