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We analyzed ophthalmic retinal optical coherence tomography (OCT) images from patients with Alzheimer's disease (AD) to identify retinal layer thickness and ratio changes that may serve as image-based biomarkers for the disease. One three-dimensional volume before and one after diagnosis for each of 48 patients were segmented to identify retinal layer and total retinal thicknesses. Between before- and after-diagnosis retinal OCT images, there were significant thickness changes in six of ten (60%) retinal layers across all 48 patients. Through a comparison with age-matched healthy subjects, the significant changes were attributed to AD only (NFL and PR2 layers), age only (GCL, IPL, and RPE layers), or both AD and age (OPL layer). Analyzing ratios of retinal layer thicknesses, 53 of 90 (58.89%) ratios had significant changes. The four independently non-significant layers were assessed to be affected by neither AD nor age (INL layer) or both AD and age (ELM, PR1, and BM layers). The demonstrated image segmentation, measurement, and ratiometric analysis of retinal layers in AD patients may yield a noninvasive OCT image-based retinal biomarker that can be used to detect retinal changes associated with this disease.

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BACKGROUND: Schools can play a major role in protecting students from skin cancer by instituting preventive policies and educational programs. METHODS: A high school-wide study was conducted to assess students' current understanding of skin cancer prevention, provide an up-to-date instruction lesson, and evaluate changes in students' knowledge and behaviors. RESULTS: Written surveys were distributed to 2,688 high school students with a return rate of 38.1% (n = 1,025). Surveys were administered prior to (survey 1), immediately after (survey 2), and 1 month after (survey 3) presenting a video lesson. Significant changes in knowledge gain (an increase from survey 1 to survey 2), knowledge decay (a decrease from survey 2 to survey 3), and knowledge persistence (an increase from survey 1 to survey 3) throughout all grade levels were found. Behavioral changes included an increase in students wearing sunscreen 5-7 days per week (p < 0.001) and students examining themselves for changing moles (p = 0.10). With this survey, the Health Education Framework for California Public Schools was revised to include updated recommendations regarding skin cancer prevention efforts in schools. CONCLUSIONS: A skin cancer video lesson given to high school students effectively increased students' knowledge and promoted healthy behaviors.

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BACKGROUND: Surgical repair of orbital floor fractures aims to improve visual function and appearance. Postoperative care often involves computed tomography (CT) imaging in addition to physical examination. It has yet to be investigated whether postoperative CT imaging influences treatment of orbital floor fractures. METHODS: A retrospective chart review was conducted for all patients who underwent orbital floor fracture repair at University of California, Irvine, from 2008 to 2017. Demographics, injury characteristics, and presurgical and postsurgical management were retrospectively extracted for 217 cases. Patients who experienced a change of care following postoperative CT (n = 6) were compared with the entire patient cohort. RESULTS: Postoperative CT imaging influenced orbital floor fracture management in 6 patients (7.2% of patients with imaging). The positive predictive value of a postoperative CT scan was 10.3%, compared with 17.6% for a physical examination. An estimated $2013.76 was spent to obtain a postoperative CT scan that revealed 1 additional patient who needed reoperation (number needed to treat = 14). A multivariate regression model demonstrated no association between postoperative CT scans and change in management (P = 0.995). CONCLUSIONS: In this patient cohort, postoperative CT imaging and its associated costs did not significantly benefit management of orbital floor fracture repair. Careful clinical physical examination should be emphasized over postoperative CT imaging to reliably determine the necessity for reoperation in orbital floor fracture management.

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Alginate hydrogels are widely used as delivery vehicles due to their ability to encapsulate and release a wide range of cargos in a gentle and biocompatible manner. The release of encapsulated therapeutic cargos can be promoted or stunted by adjusting the hydrogel physiochemical properties. However, the release from such systems is often skewed towards burst-release or lengthy retention. To address this, we hypothesized that the overall magnitude of burst release could be adjusted by combining microgels with distinct properties and release behavior. Microgel suspensions were generated using a process we have termed on-chip polymer blending to yield composite suspensions of a range of microgel formulations. In this manner, we studied how alginate percentage and degradation relate to the release of lentivectors. Whereas changes in alginate percentage had a minimal impact on lentivector release, microgel degradation led to a 3-fold increase, and near complete release, over 10 days. Furthermore, by controlling the amount of degradable alginate present within microgels the relative rate of release can be adjusted. A degradable formulation of microgels was used to deliver vascular endothelial growth factor (VEGF)-encoding lentivectors in the chick chorioallantoic membrane (CAM) assay and yielded a proangiogenic response in comparison to the same lentivectors delivered in suspension. The utility of blended microgel suspensions may provide an especially appealing platform for the delivery of lentivectors or similarly sized therapeutics. STATEMENT OF SIGNIFICANCE: Genetic therapeutics hold considerable potential for the treatment of diseases and disorders including ischemic cardiovascular diseases. To realize this potential, genetic vectors must be precisely and efficiently delivered to targeted regions of the body. However, conventional methods of delivery do not provide sufficient spatial and temporal control. Here, we demonstrate how alginate microgels provide a basis for developing systems for controlled genetic vector release. We adjust the physiochemical properties of alginate for quicker or slower release, and we demonstrate how combining distinct formulations of microgels can tune the release of the overall composite microgel suspension. These composite suspensions are generated using a straightforward and powerful application of droplet microfluidics which allows for the real-time generation of a composite suspension.

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