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Purpose: To demonstrate the biocompatibility of SIBS implants as compared to PDMS implants in the treatment of retinal detachment in New Zealand White (NZW) rabbit model.1,2 Introduction: Scleral encircling bands, fixation rings and buckles are utilized for closure of retinal breaks and retina reattachment. The FDA approved PDMS-implant is associated with several post-operative complications, involving thick-fibrotic encapsulations. SIBS, an elastomeric triblock copolymer, was recently FDA approved for use in a cardiovascular drug eluting stent (TAXUSTM, Boston Scientific Corp., MA) and showed excellent biocompatibility and slow drug release capability. Materials and Methods: SIBS (9-mol%-styrene) implants were fabricated (InnFocus LLC, USA) to match PDMS implants (Labtician, Inc, Canada) dimensions. 5 NZW rabbits received SIBS and 4, PDMS-implants. Post-operative exam sequence: day 1 and 2, week 1, 2, 3, 4 and 6, and monthly thereafter for up to 1 year. Anatomohistopathology exams sequence: one SIBS animal at 6 weeks and one animal of each treatment group at 3 and 6-months, and two at 12-months. Results: SIBS compared to PDMS animals exhibited less inflammation and a better buckling effect during the first 6 weeks. At POD 9 months, the conjunctival injection in the SIBS rabbit was none as opposed to the PDMS value and the buckling effect for both groups were equal. There were no visible signs of encapsulation with SIBS. There were no infections in the 9 animals and none of the implants extruded thus far (

Purpose: To assess the efficacy of a novel orbital tissue expander (OTE) in treating congenital anophthalmic and microphthalmic infants. Methods: The OTE implant is an inflatable (0.5 to >6cc) silicone rubber globe sliding on a titanium T-shaped bone plate secured to the temporal bone with 1mm titanium screws. In vitro testing was performed to assess injection volume versus diameter measurements to determine consistency between devices, flex fatigue for durability of the implants when compressed, weight change in isotonic saline at 37°C to mimic human body temperature, seal durability by puncturing the globe numerous times while inflating, capacity before rupture to determine the maximum amount of saline it is able to contain, and effective sterilization. Ex-vivo testing was performed for adjustments prior to in vivo study. An OTE was then implanted in five 2-week old kittens (OS only) and inflated in 0.5cc increments. Three control animals received enucleation alone. All 8 animals were followed for 18 weeks and underwent euthanasia for morphological and histopathological analysis. Results: In vitro testing confirmed a

Purpose: To design and test the Miami-InnFocus Drainage Implant (MiDi) as a glaucoma shunt that is biocompatible, flexible, and significantly smaller than existing commercial implants in order to prevent postoperative hypotony, inflammation, scarring, erosion, and extrusion. Methods: A new biomaterial composed of styrene-b-isobutylene-b-styrene (SIBS) was used in a novel design for a glaucoma drainage implant. The implant consists of a tube 11mm long with an inner diameter of 70, 100, and 150 μm and outer diameter of 250 μm with a 1mm 2 tab located 4.5mm from the proximal tip to prevent migration. The device was implanted in 15 New Zealand White rabbits for biocompatibility and efficacy testing. A similarly designed implant made of polydimethylsiloxane was implanted in 6 other animals as a pseudo-control. Typical GDI implantation technique was modified for this device. The proximal end of the new SIBS implant was inserted 2mm into the anterior chamber and the distal end placed in a subconjunctival space created by the surgeon. Biocompatibility of the device was studied by slit-lamp follow-up and intraocular pressure (IOP) measurements recorded periodically. Results: Biocompatibility of the MiDi was excellent. A low and diffuse bleb was observed with these devices. All SIBS tubes were patent 9 months after insertion. Immunostaining demonstrated non-continuous deposition of collagen with virtually no encapsulation. No macrophages or myofibroblast were visible around the SIBS polymer which was found more bioinert than the control PDMS. Conclusion: This newly designed glaucoma implant is clinically biocompatible in the rabbit model and maintained 100% patency at 9 months.