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PURPOSE To evaluate 5-year functional outcomes involving the inner retina after epiretinal membrane (ERM) surgery. METHODS The study eye (SE) and fellow eye (FE) of 20 patients undergoing ERM surgery were examined preoperatively and at 3, 12, 24, 36, 48, and 60 months postoperatively. Retinal nerve fiber layer and ganglion cell-inner plexiform layer (GC-IPL) thicknesses were analyzed using spectral domain optical coherence tomography. Humphrey visual field mean deviation, pattern SD, and qualitative changes were assessed and compared over time. RESULTS Mean GC-IPL thickness in SEs was less than that of FEs at all time points with progressive thinning in SEs after ERM surgery. There was significant thinning of the superotemporal GC-IPL in SEs as compared to FEs at 3 months and 60 months (P < 0.05). Humphrey visual field mean deviation was greater in SEs as compared to FEs but statistically significant only at 0, 12, and 24 months (P < 0.05). Pattern SD increased from baseline in SEs but remained near baseline in FEs. CONCLUSION Surgical eyes after ERM surgery demonstrated progressive thinning of the GC-IPL and transient worsening trends in Humphrey visual field mean deviation and pattern SD as compared to controls after ERM surgery.

Many animal models of retinoblastoma exist, each of which recapitulates some, but not all, of the features of human disease. The most commonly used models that are available are described in this chapter. These include various genetic and xenograft models of retinoblastoma and include a multitude of species, such as mice, rats, rabbits, pigs, and nonhuman primates. A wide array of uses of animal models in retinoblastoma research are presented here, including those for the study of tumor biology and response to treatment, assessment of pharmacokinetics, and measurement of chemotherapeutic toxicity and efficacy for drug discovery. Importantly, we discuss the relative strengths and limitations of each model. Factors for investigators to consider in designing various types of experiments are highlighted, including type of tumor model (genetic or xenograft), immune status (native, immunologically naive, genetically immunocompromised, or pharmacologically immunosuppressed), and choice of species. While a particular model may be ideal for a certain use, no single model is appropriate for all experiments. Species-specific factors are especially critical when studying regional and local chemotherapy delivery.

Visual toxicities from ethambutol are rare but represent one of the few causes of non-glaucomatous and non-compressive bitemporal hemianopsia. The authors present a six-patient case series illustrating variable clinical presentation and reversibility of visual loss in patients treated with ethambutol for Mycobacterium avium complex, including four patients who presented with visual field defects suggestive of bitemporal hemianopsia. Two additional patients were being followed for glaucoma, developed visual field defects with ethambutol treatment, and subsequently recovered with cessation of drug. In patients being treated with ethambutol, reversible bitemporal hemianopsia was the most commonly noted presentation of ethambutol toxicity.

Diabetic retinopathy is characterized by progressive vascular dropout with subsequent vision loss. We have recently shown that an intravitreal injection of adipose-derived stem cells (ASCs) can stabilize the retinal microvasculature, enabling repair and regeneration of damaged capillary beds in vivo. Because an understanding of ASC status from healthy versus diseased donors will be important as autologous cellular therapies are developed for unmet clinical needs, we took advantage of the hyperglycemic Akimba mouse as a preclinical in vivo model of diabetic retinopathy in an effort aimed at evaluating therapeutic efficacy of adipose-derived stem cells (mASCs) derived either from healthy, nondiabetic or from diabetic mice. To these ends, Akimba mice received intravitreal injections of media conditioned by mASCs or mASCs themselves, subsequent to development of substantial retinal capillary dropout. mASCs from healthy mice were more effective than diabetic mASCs in protecting the diabetic retina from further vascular dropout. Engrafted ASCs were found to preferentially associate with the retinal vasculature. Conditioned medium was unable to recapitulate the vasoprotection seen with injected ASCs. In vitro diabetic ASCs showed decreased proliferation and increased apoptosis compared with healthy mASCs. Diabetic ASCs also secreted less vasoprotective factors than healthy mASCs, as determined by high-throughput enzyme-linked immunosorbent assay. Our findings suggest that diabetic ASCs are functionally impaired compared with healthy ASCs and support the utility of an allogeneic injection of ASCs versus autologous or conditioned media approaches in the treatment of diabetic retinopathy. Significance This work addresses the therapeutic potential of stem cells that are obtained from diabetic donors, and the clinical focus of our work is diabetic retinopathy. This work examined how injected murine adipose-derived stem cells (ASCs) affect the retinal microvasculature in a mouse model of diabetic retinopathy. Results show that ASCs obtained from healthy mice secrete angiogenic growth factors and promote retinal vascular stability when they are injected intravitreally. The findings further suggest that ASCs obtained from diabetic mice have a diminished ability to support the retinal vasculature in this mouse model of retinal vasculopathy.

Autologous fat grafting is a widely used technique in plastic and reconstructive surgery. Despite decades of clinical practice, a standardized procedure has yet to be adopted by all practitioners. One of the most critical disadvantages of this technique is the unpredictable post-surgical volume loss over time (1). Among the variables that remain to be standardized, harvesting technique, processing method, and injection technique are considered the most critical. The loss of grafted tissue could be explained by the lack of adequate vascularization, the lack of regenerative cells within the fat graft, the traumatic handling of the fat during preparation and implantation, immune system-mediated cellular phagocytosis in the pro-inflammatory environment after grafting, or likely a combination of all of these effects (2). Various methods for harvesting and processing of autologous fat grafts have been described and analyzed in the literature. One of the standard procedures, the Coleman technique (3-4), uses aspiration at reduced vacuum levels and centrifugation to concentrate adipose tissue. Other techniques use straining through a mesh to obtain the adipose tissue. However, none of these methods utilize an efficient washing system to remove red blood cells, free oils, cellular breakdown products such as LDH (lactate dehydrogenase), or anesthetic substances. The rationale for performing this study is to obtain data which address questions regarding the adipose tissue physiological conditions as harvested (raw lipoaspirate) and after washing using isotonic saline solution. Adipose samples were collected with standard liposuction technique from 5 healthy females donors after signing informed consent. One half of the samples were decanted without washing, while the other half were washed using a CE-marked device that had been developed to process large volumes of human lipoaspirates (GID Group, Inc, Louisville, CO). The aqueous phase of the tissues were quantitatively analyzed for triglyceride content (TGC), LDH, hematocrit, and osmolarity using an automated analyzer (Dimension RxL Max analyzer, Siemens). All results are expressed as means ± SEM (n = 5). The unpaired Student's t-test was used to compare the different values analyzed between the decanted and washed adipose tissue. Compared to decanted adipose, washed adipose demonstrated marked and significant reductions in triglycerides (6.4 fold increase of triglyceride content in the unwashed lipoaspirate sample), LDH (unwashed lipoaspirate produced 3-4 fold more LDH than GID washed) and hematocrit (unwashed lipoaspirate produced almost 8 fold more hematocrit than GID washed). The levels of TGCs and free hemoglobin have been previously described to promote inflammation and mediate different pathways that lead to nitric oxide depletion and reactive oxidative species generation (5). Importantly, washing the adipose resulted in a restoration of adipose graft osmolarity to within a normal physiological range. (See figures 1 and ​and22). Figure 1 Representative images of unwashed lipoaspirate (A and C, left) and washed lipoaspirate (B and D, right) after decantation. Note raw lipoaspirate on GID700 device before and after washing. Figure 2 Comparison of TGC content (A), LDH release (B), hematocrit (C) and osmolarity (D) in decanted adipose compared to GID washed adipose. ★★★ (p < 0.001), ★ (p < 0.05), ★★ (p < 0.01) ... The raw lipoaspirate is subjected to hyperosmolar conditions (more than 300 mOsm/L) and is contaminated with red blood cells, free hemoglobin and free oils. In this study we demonstrate that the use of a fast and efficient washing system allows the fat graft to be returned to optimal physiological conditions for reimplantation.

Background Retinal vasculopathies, including diabetic retinopathy (DR), threaten the vision of over 100 million people. Retinal pericytes are critical for microvascular control, supporting retinal endothelial cells via direct contact and paracrine mechanisms. With pericyte death or loss, endothelial dysfunction ensues, resulting in hypoxic insult, pathologic angiogenesis, and ultimately blindness. Adipose-derived stem cells (ASCs) differentiate into pericytes, suggesting they may be useful as a protective and regenerative cellular therapy for retinal vascular disease. In this study, we examine the ability of ASCs to differentiate into pericytes that can stabilize retinal vessels in multiple pre-clinical models of retinal vasculopathy. Methodology/Principal Findings We found that ASCs express pericyte-specific markers in vitro. When injected intravitreally into the murine eye subjected to oxygen-induced retinopathy (OIR), ASCs were capable of migrating to and integrating with the retinal vasculature. Integrated ASCs maintained marker expression and pericyte-like morphology in vivo for at least 2 months. ASCs injected after OIR vessel destabilization and ablation enhanced vessel regrowth (16% reduction in avascular area). ASCs injected intravitreally before OIR vessel destabilization prevented retinal capillary dropout (53% reduction). Treatment of ASCs with transforming growth factor beta (TGF-β1) enhanced hASC pericyte function, in a manner similar to native retinal pericytes, with increased marker expression of smooth muscle actin, cellular contractility, endothelial stabilization, and microvascular protection in OIR. Finally, injected ASCs prevented capillary loss in the diabetic retinopathic Akimba mouse (79% reduction 2 months after injection). Conclusions/Significance ASC-derived pericytes can integrate with retinal vasculature, adopting both pericyte morphology and marker expression, and provide functional vascular protection in multiple murine models of retinal vasculopathy. The pericyte phenotype demonstrated by ASCs is enhanced with TGF-β1 treatment, as seen with native retinal pericytes. ASCs may represent an innovative cellular therapy for protection against and repair of DR and other retinal vascular diseases.

PURPOSE To construct a low-cost, easy-to-use, high-image-quality mydriatic fundus camera with "point-and-shoot" operation, and to evaluate the efficacy of this camera to accurately document retinal disease. METHODS A prototype portable fundus camera was designed by interfacing a novel optical module with a Panasonic Lumix G2 consumer camera. Low-cost, commercially available optics were used to create even illumination of the fundus, providing a 50° retinal field of view. A comparative study assessing the image quality of the prototype camera against a traditional tabletop fundus camera was conducted under an Institutional Review Board (IRB)-approved study. RESULTS A stand-alone, mydriatic camera prototype was successfully developed at a parts cost of less than $1000. The prototype camera was capable of operating in a point-and-shoot manner with automated image focusing and exposure, and the image quality of fundus photos was comparable to that of existing commercial cameras. Pathology related to both nonproliferative and proliferative diabetic retinopathy and age-related macular degeneration was easily identified from fundus images obtained from the low-cost camera. CONCLUSIONS Early prototype development and clinical testing have shown that a consumer digital camera can be inexpensively modified to image the fundus with professional diagnostic quality. The combination of low cost, portability, point-and-shoot operation, and high image quality provides a foundational platform on which one can design an accessible fundus camera to screen for eye disease.

PURPOSE EphB4 and ephrinB2 are known key regulators of retinal vascular development, but due to their capacity for bidirectional signaling, delineation of their individual roles in this process remains unclear. To better dissect out individual contributions, a model of proliferative retinopathy in mice with attenuated ephrinB2 reverse signaling was studied. It was hypothesized that endothelial ephrinB2 reverse signaling regulates hypoxia-induced capillary sprouting, as well as the pathologic formation of neovascular tufts in postnatal retinal microvascular networks. METHODS Genetically manipulated mice with attenuated ephrinB2 reverse signaling (ephrinB2(lacZ/+)), along with wild-type (WT) controls, were exposed to oxygen-induced retinopathy (OIR), a postnatal model of proliferative retinopathy. At peak disease (postnatal day 18), microvascular networks were analyzed to examine intraretinal revascularization, capillary sprouting, and pathologic neovascularization responses. EphB4 and phosphorylated ephrinB protein expression patterns along retinal microvessels were also assessed. RESULTS EphrinB2(lacZ/+) mice exhibited reduced hypoxia-induced revascularization (P ≤ 0.04) and reduced formation of neovascular tufts (P < 0.001), as compared with WT controls. Corresponding to the observed inhibition of retinal angiogenesis, ephrinB2(lacZ/+) retinas displayed an increased number of blind-ended capillary sprout tips (P < 0.02) and endothelial filopodial processes (P = 0.001). In WT and ephrinB2(lacZ/+) OIR-exposed retinas, ephrinB was confined to endothelial cells, with expression detected along angiogenic vascular processes including neovascular tufts and blind-ended capillary sprouts. CONCLUSIONS EphrinB2 reverse signaling is a regulator of key processes during retinal vascularization and controls pathologic retinal angiogenesis through direct effects on capillary sprouting and endothelial filopodia formation.

This article reports on a project that analyzed the long-range implications of two alternative development paths for California through the year 2050. One development path or scenario emphasizes continued industrial growth and material abundance, the other scenario directing growth toward higher quality, more durable goods, and less resource-intensive growth patterns. The project begins with an analysis of the world and national context for California's development, and concludes that immigration pressures and demand for California products are so high that a no growth scenario is virtually impossible for California. The two more feasible growth scenarios, which roughly bound the potential range of growth, are projected in detail for population, industry, transportation, and agriculture. Based on these development path alternatives, energy demand and supply alternatives are analyzed. The resulting energy demand levels differ by over 250%. Supply choices are largely dictated by the demand level: No feasible supply mixes were found that would avoid extensive dependence on nuclear power and synthetic fuels at high demand levels. Finally, environmental and policy implications are presented.