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OBJECTIVE: The aim of this study was to evaluate the visual outcome, uveitis control, and complications following cataract surgery for intraocular lens (IOL) implantation in patients with a known diagnosis of uveitis. DESIGN: The study was a retrospective interventional case series. PARTICIPANTS: We reviewed 98 patients (137 eyes) with adult uveitis undergoing cataract surgery with foldable acrylic posterior chamber IOL implantation between 2003 and 2013 in 2 uveitis practices. METHODS: Best-corrected visual acuity (BCVA) and uveitis grade (Standardized Uveitis Nomenclature criteria) were measured at 1 month preoperatively, at postoperative week 1, and at postoperative months 1, 6, and 12. The main outcome measures were mean change in postoperative BCVA, uveitis grade, and complications. RESULTS: Of the eyes studied, 84% had grade 0-0.5 anterior uveitis at postoperative week 1 and maintained uveitis control (77% grade 0; 19% grade 0.5 anterior uveitis) at 1 year postoperatively. None of the patients had active intermediate or posterior uveitis at any time point. Mean BCVA improved from 0.71 ± 0.38 logMAR preoperatively to 0.37 ± 0.36 at 6 months (p < 0.01) and to 0.30 ± 0.25 at 12 months (p = 0.01) postoperatively. Of the study participants, 30% had preoperative complications related to uveitis, including epiretinal membrane (12%), cystoid macular edema (12%), and glaucoma (5.8%); 46% of patients had small pupils as a result of posterior synechiae. Postoperative vision-limiting complications included posterior capsule opacification (18%), epiretinal membrane (9.0%), and cystoid macular edema (8.8%). Of the eyes studied, 5.8% underwent Nd:YAG capsulotomy. CONCLUSIONS: Cataract surgery with acrylic posterior-chamber IOL implantation is effective at improving visual acuity in patients with uveitis. Uveitis was well controlled in the majority of our study patients for 12 months after cataract surgery. The most frequent vision-limiting postoperative complication was posterior capsule opacification, which was treatable with Nd:YAG capsulotomy.

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Automated video object recognition is a topic of emerging importance in both defense and civilian applications. This work describes an accurate and low-power neuromorphic architecture and system for real-time automated video object recognition. Our system, Neuormorphic Visual Understanding of Scenes (NEOVUS), is inspired by computational neuroscience models of feed-forward object detection and classification pipelines for processing visual data. The NEOVUS architecture is inspired by the ventral (what) and dorsal (where) streams of the mammalian visual pathway and integrates retinal processing, object detection based on form and motion modeling, and object classification based on convolutional neural networks. The object recognition performance and energy use of the NEOVUS was evaluated by the Defense Advanced Research Projects Agency (DARPA) under the Neovision2 program using three urban area video datasets collected from a mix of stationary and moving platforms. These datasets are challenging and include a large number of objects of different types in cluttered scenes, with varying illumination and occlusion conditions. In a systematic evaluation of five different teams by DARPA on these datasets, the NEOVUS demonstrated the best performance with high object recognition accuracy and the lowest energy consumption. Its energy use was three orders of magnitude lower than two independent state of the art baseline computer vision systems. The dynamic power requirement for the complete system mapped to commercial off-the-shelf (COTS) hardware that includes a 5.6 Megapixel color camera processed by object detection and classification algorithms at 30 frames per second was measured at 21.7 Watts (W), for an effective energy consumption of 5.45 nanoJoules (nJ) per bit of incoming video. These unprecedented results show that the NEOVUS has the potential to revolutionize automated video object recognition toward enabling practical low-power and mobile video processing applications.

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This study investigates the effects of profound acquired unilateral deafness on the adult human central auditory system by analyzing long-latency auditory evoked potentials (AEPs) with dipole source modeling methods. AEPs, elicited by clicks presented to the intact ear in 19 adult subjects with profound unilateral deafness and monaurally to each ear in eight adult normal-hearing controls, were recorded with a 31-channel system. The responses in the 70-210 ms time window, encompassing the N1b/P2 and Ta/Tb components of the AEPs, were modeled by a vertically and a laterally oriented dipole source in each hemisphere. Peak latencies and amplitudes of the major components of the dipole waveforms were measured in the hemispheres ipsilateral and contralateral to the stimulated ear. The normal-hearing subjects showed significant ipsilateral-contralateral latency and amplitude differences, with contralateral source activities that were typically larger and peaked earlier than the ipsilateral activities. In addition, the ipsilateral-contralateral amplitude differences from monaural presentation were similar for left and for right ear stimulation. For unilaterally deaf subjects, the previously reported reduction in ipsilateral-contralateral amplitude differences based on scalp waveforms was also observed in the dipole source waveforms. However, analysis of the source dipole activity demonstrated that the reduced inter-hemispheric amplitude differences were ear dependent. Specifically, these changes were found only in those subjects affected by profound left ear unilateral deafness.

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OBJECTIVES: Previous studies have shown that observed patterns of auditory evoked potential (AEP) maturation depend on the scalp location of the recording electrodes. Dipole source modeling incorporates the AEP information recorded at all electrode locations. This should provide a more robust description of auditory system maturation based on age-related changes in AEPs. Thus, the purpose of this study was to evaluate central auditory system maturation based dipole modeling of multi-electrode long-latency AEPs recordings. METHODS: AEPs were recorded at 30 scalp-electrode locations from 118 subjects between 5 and 20 years of age. Regional dipole source analysis, using symmetrically located sources, was used to generate a spatio-temporal source model of age-related changes in AEP latency and magnitude. RESULTS: The regional dipole source model separated the AEPs into distinct groups depending on the orientation of the component dipoles. The sagittally oriented dipole sources contained two AEP peaks, comparable in latency to Pa and Pb of the middle latency response (MLR). Although some magnitude changes were noted, latencies of Pa and Pb showed no evidence of age-related change. The tangentially oriented sources contained activity comparable to P1, N1b, and P2. There were various age-related changes in the latency and magnitude of the AEPs represented in the tangential sources. The radially oriented sources contained activity comparable to the T-complex, including Ta, and Tb, that showed only small latency changes with age. In addition, a long-latency component labeled TP200 was observed. CONCLUSIONS: It is possible to distinguish 3 maturation groups: one group reaching maturity at age 6 and comprising the MLR components Pa and Pb, P2, and the T-complex. A second group that was relatively fast to mature (50%/year) was represented by N2. A third group was characterized by a slower pattern of maturation with a rate of 11-17%/year and included the AEP peaks P1, N1b, and TP200. The observed latency differences combined with the differences in maturation rate indicate that P2 is not identical to TP200. The results also demonstrated the independence of the T-complex components, represented in the radial dipoles, from the P1, N1b, and P2 components, contained in the tangentially oriented dipole sources.

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