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PURPOSE. To assess the application of optical frequency domain imaging (OFDI) at 1050 nm for the detection of choroidal neovascularization (CNV) in age-related macular degeneration (AMD) and its response to treatment. Three patients presenting with blurred vision and exudative AMD were imaged before and after anti-VEGF treatment with ranibizumab. METHODS. The patients were imaged with OFDI, a swept-source-based, high-speed optical coherence tomography (OCT) system developed at the Wellman Center for Photomedicine. A center wavelength of 1050 nm was used that has been demonstrated to provide better imaging of the deeper structures of the retina below the RPE, such as the choroidal vasculature. Three-dimensional data sets were acquired in 2 to 4 seconds. RESULTS. En face images were compiled from cross-sectional OFDI data and correlated with color fundus photography (CF) and fluorescein angiograms (FAs). Cross-sectional images were coregistered with CF and FA to obtain depth-resolved information about CNV, CNV volume, retinal thickness, subretinal fluid volume and height of neurosensory detachment before and after treatment with ranibizumab. A band of reduced reflectivity below the RPE was identified in all three subjects that corresponded to areas of confirmed and suspected occult CNV on FA. After treatment, this band was reduced in volume in all patients. CONCLUSIONS. High-speed 3-D OFDI at 1050 nm is a promising technology for imaging the retina and choroid in neovascular AMD. The developed system at 1050 nm provides good contrast for occult (type 1) CNV and may have advantages compared with time domain and current state of the art spectral domain OCT systems (SD-OCT) at 850 nm. Copyright © Association for Research in Vision and Ophthalmology.

PURPOSE. To assess the biocompatibility of materials for possible use in subretinal prostheses. METHODS. Strips (0.5 5 mm; 10-m thick) of either plain poly(imide) or poly(imide) coated with amorphous aluminum oxide (AAO), amorphous carbon (AC), parylene, poly(vinyl pyrrolidone) (PVP), or poly(ethylene glycol) (PEG) were each implanted into the subretinal space of four Yucatan miniature pigs. Two types of control surgery without implantation were performed in four other animals. Electroretinograms (ERGs) were performed before and after surgery. All animals were euthanatized 3 months after surgery, and histologic slides of the retina were assessed for 15 criteria. Paired, two-tailed Student’s t-tests were used for statistical analyses. RESULTS. Across all animals, the mean amplitude of the ERG b-wave did not differ from baseline after 3 months. In implanted animals, the histologic analyses revealed that (1) all the implanted materials produced abnormalities that were significantly greater than in the control subjects; (2) overall, PEG, parylene, and PVP produced less histologic disruption than the other three materials; (3) parylene and PEG did not differ significantly from the control in disturbing retinal anatomy; (4) only PI and AAO produced RPE alterations that were significantly greater than in control subjects; and (5) AAO and PI produced a significantly greater degree of peri-implant cellular responses than did the other materials. CONCLUSIONS. All implants produced some alteration of the retina, but there were clear differences among the materials in the degree to which their presence disturbed the normal anatomy of the retina or RPE or incited tissue reactions around the implant. (Invest Ophthalmol Vis Sci. 2006;47:3514 –3522)