SBIR-STTR Award

This Phase 1 application proposes to develop, evaluate and refine potential biodegradable polymers to be used intraocularly to tamponade the retina to the choriocapillaris following retinal detachment surgery. Specifically, the Principal Investigator intends to identify several non-toxic polymer formulations that can be polymerized by photoactivation or self-polymerization within the vitreous cavity. The assembled team will then evaluate the ability of these formulations to close retinal breaks using an experimental rabbit eye system. The overall toxicity, duration of attachment to the retina and the effectiveness of the polymer formulations will then be tested and an optimal non-toxic biodegradable polymer formulation identified. The proposed product will replace the use of silicon oil or gas that is currently used to tamponade the retina following laser photocoagulation or cryotherapy to repair retinal breaks. For this project, the Principal Investigator has recruited an experienced retinal surgeon who will perform the retinal surgeries and develop the rabbit eye model of retinal detachment. Additionally, the PI has obtained the co-operation of a biomedical engineerer who has considerable experience in biocompatible polymer development.Proposed Commercial Application:Closure of retinal holes and breaks during retinal detachment surgery. Providing intraocular tamponade during chorioadhesive scar formation following vitrectomy and retinal detachment surgery.

Thesaurus Terms:
biomaterial development /preparation, biomaterial evaluation, cryotherapy, intercellular cementing substance, method development, nonhuman therapy evaluation, photocoagulation therapy, polymer, retina detachment biomaterial compatibility, laser therapy, photoactivation, polymerization laboratory rabbitNATIONAL EYE INSTITUTE

Closure of retinal breaks requires creation of chorioretinal adhesion around each break with either laser photocoagulation or cryotherapy followed by intraocular tamponade with gas or silicone oil. When gases are used, patients must keep their head in a face down position for 2 weeks after surgery. This causes considerable discomfort in most patients, and not uncommonly, is the most difficult hurdle in post-operative management. Additionally, gas is associated with ocular complications including cataract and glaucoma. Silicone oil has the advantage that the patient is not required to position face down for more that one day post-operatively. However, unlike gas, which is slowly reabsorbed into the blood stream, silicone must be surgically removed from the eye as a secondary procedure to prevent similar ocular complications. To address these problems, Calhoun Vision, Inc. is developing, evaluating, and refining biodegradable polymers for the closure of retinal breaks. In the proposed research we will optimize non-toxic polymer formulations that can close retinal breaks in an experimental system. We will assess the toxicity, duration of attachment to the retinal, and effectiveness of several polymer formulations. Polymer composition will be varied to achieve the optimal non-toxic biodegradable polymer formulation.

Thesaurus Terms:
biodegradable product, biomaterial development /preparation, biomaterial evaluation, photochemistry, polymer, retina detachment biomaterial compatibility, laser therapy, photoactivation, polymerization histopathology, laboratory rabbit