Evaluation of a novel biomaterial in the suprachoroidal space of the rabbit eye.
OBJECTIVE
Drug delivery to treat diseases of the posterior segment of the eye, such as choroidal neovascularization and its complications, is hampered by poor intraocular penetration and rapid elimination of the drug from the eye. The purpose of this study was to investigate the feasibility and tolerance of suprachoroidal injections of poly(ortho ester) (POE), a bioerodible and biocompatible polymer, as a biomaterial potentially useful for development of sustained drug delivery systems.


METHODS
After tunnelization of the sclera, different formulations based on POE were injected (100 microL) into the suprachoroidal space of pigmented rabbits and compared with 1% sodium hyaluronate. Follow-up consisted of fundus observations, echography, fluorescein angiography, and histologic analysis over 3 weeks.


RESULTS
After injection, POE spread in the suprachoroidal space at the posterior pole. It was well tolerated and progressively disappeared from the site of injection without sequelae. No bleeding or retinal detachment occurred. Echographic pictures showed that the material was present in the suprachoroidal space for 3 weeks. Angiography revealed minor pigment irregularities at the site of injection, but no retinal edema or necrosis. Histology showed that POE was well tolerated in the choroid.


CONCLUSIONS
POE suprachoroidal injections, an easy, controllable, and reproducible procedure, were well tolerated in the rabbit eye. POE appears to be a promising biomaterial to deliver drugs focally to the choroid and the retina.
Einmahl
Suzanne
S
Department of Pharmaceutical Technology and Biopharmaceutics, School of Pharmacy, University of Geneva, 30 quai Ernest-Ansermet, 1211 Geneva 4, Switzerland.
Savoldelli
Michelle
M
D'Hermies
François
F
Tabatabay
Cyrus
C
Gurny
Robert
R
Behar-Cohen
Francine
F
D000818:Animals; D001672:Biocompatible Materials / Q000633:toxicity*; D002829:Choroid / Q000000981:diagnostic imaging / Q000187:drug effects* / Q000473:pathology; D016503:Drug Delivery Systems; D004353:Drug Evaluation, Preclinical; D005110:Extracellular Space / Q000000981:diagnostic imaging / Q000187:drug effects; D005240:Feasibility Studies; D005260:Female; D005451:Fluorescein Angiography; D006820:Hyaluronic Acid / Q000633:toxicity; D007267:Injections; D011108:Polymers / Q000633:toxicity*; D011817:Rabbits; D014463:Ultrasonography
D001672:Biocompatible Materials; D011108:Polymers; C401107:poly(ortho ester); D006820:Hyaluronic Acid