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Eliot R Dow,1– 3 Karen M Chen,1 Cindy S Zhao,1 Austen N Knapp,1 Anuradha Phadke,4 Kirsti Weng,4 Diana V Do,1 Vinit B Mahajan,1 Prithvi Mruthyunjaya,1 Theodore Leng,1 David Myung1,2 1Department of Ophthalmology, Byers Eye Institute at Stanford, Palo Alto, CA, USA; 2Department of Ophthalmology, Veterans Affairs Palo Alto Health Care System, Palo Alto, CA, USA; 3Department of Ophthalmology, Duke Eye Center, Durham, NC, USA; 4Department of Internal Medicine, Stanford Health Care, Palo Alto, CA, USACorrespondence: David Myung, Byers Eye Institute at Stanford, Palo Alto, CA, 94303, USA, Tel +1 650 723-6995, Email djmyung@stanford.eduPurpose: We examine the rate of and reasons for follow-up in an Artificial Intelligence (AI)-based workflow for diabetic retinopathy (DR) screening relative to two human-based workflows.Patients and Methods: A DR screening program initiated September 2019 between one institution and its affiliated primary care and endocrinology clinics screened 2243 adult patients with type 1 or 2 diabetes without a diagnosis of DR in the previous year in the San Francisco Bay Area. For patients who screened positive for more-than-mild-DR (MTMDR), rates of follow-up were calculated under a store-and-forward human-based DR workflow (“Human Workflow”), an AI-based workflow involving IDx-DR (“AI Workflow”), and a two-step hybrid workflow (“AI–Human Hybrid Workflow”). The AI Workflow provided same-day results, whereas the other workflows took 1– 5 days. Patients were surveyed by phone about follow-up decisions.Results: Under the AI Workflow, 279 patients screened positive for MTMDR. Of these, 69.2% followed up with an ophthalmologist within 90 days. Altogether 70.5% (N=48) of patients who followed up chose their location based on primary care referral. Under the Human Workflow and AI–Human Hybrid Workflow, 12.0% (N=14/117) and 11.7% (N=12/103) of patients with a referrable screening result followed up compared to 35.5% of patients under the AI Workflow (N=99/279; χ2df=2 = 36.70, p < 0.00000001).Conclusion: Ophthalmology follow-up after a positive DR screening result is approximately three-fold higher under the AI Workflow than either the Human Workflow or AI–Human Hybrid Workflow. Improved follow-up behavior may be due to the decreased time to screening result.Keywords: telemedicine, teleophthalmology, fundus photography, deep learning, machine learning, referral

Saloni Vishwakarma,1 Durga S Borkar,2 Andrew LaPrise,1 Michael Mbagwu,1 Theodore Leng3 1Quantitative Sciences Department, Verana Health, San Francisco, CA, USA; 2Ophthalmology Department, Duke University Eye Center, Duke University School of Medicine, Durham, NC, USA; 3Ophthalmology Department, Byers Eye Institute at Stanford, Stanford University School of Medicine, Palo Alto, CA, USACorrespondence: Theodore Leng, Byers Eye Institute, Stanford University School of Medicine, 2452 Watson Court, Palo Alto, CA, 94303, USA, Tel +1 (650) 498 4262, Fax +1 (888) 565-2640, Email tedleng@stanford.eduPurpose: To investigate patterns of ancillary imaging testing among vitreoretinal specialists for patients with vitreoretinal disease in the United States (US).Methods: Optical coherence tomography (OCT), color fundus photography (CFP), and fluorescein angiography (FA), ordered by vitreoretinal specialists and documented within the American Academy of Ophthalmology IRIS® Registry (Intelligent Research in Sight) between 01 January 2018 and 31 December 2020, were retrospectively assessed. Trends in imaging modality choice were analyzed by payer type, geographic region, and practice type. Sub-analyses were conducted according to categorization of vitreoretinal specialists into those treating a high versus low volume of patients with neovascular age-related macular degeneration (nAMD).Results: OCT was the most common imaging modality used, followed by CFP and FA. Following normalization, the highest volume of OCT procedures performed were identified among Medicare Advantage and Medicare Fee-for-Service beneficiaries, within the South of the US, and at medium and large practices. Minimal differences were observed for CFP and FA volume across payer types and regions. Across practice types, the largest volume of CFP and FA procedures were identified in small and private equity owned practices, respectively. Vitreoretinal specialists with a high nAMD volume more frequently performed OCT than those with a low nAMD volume.Conclusion: Vitreoretinal specialists demonstrated a strong preference for OCT, with real-world associations according to payer type, geographic location, and practice type. Volume of nAMD patients seen impacted the likelihood of specialists ordering OCTs.Plain Language Summary: Optical coherence tomography (OCT), color fundus photography (CFP), and fluorescein angiography (FA) are key imaging modalities used by vitreoretinal specialists in routine eye care. This study aimed to uncover patterns of OCT, CFP, and FA usage in the United States from 2018 to 2020, and investigated the impact of volume of patients with neovascular age-related macular degeneration on these trends. Higher rates of OCT use, compared with CFP and FA, were identified in the US.Keywords: color fundus photography, fluorescein angiography, optical coherence tomography, retinal disease, vitreoretinal disease

Sarah Cheng, Theodore Leng Department of Ophthalmology, Byers Eye Institute at Stanford, Stanford University School of Medicine, Palo Alto, CA, USA Background and objectives: A method of identifying retinal vascular microaneurysms (MAs) in nonproliferative diabetic retinopathy (NPDR) using swept-source optical coherence tomography (SS-OCT). Patients and methods: SS-OCT images were acquired in 17 eyes with NPDR using prototype SS-OCT device and fluorescein angiography (FA) images were obtained simultaneously. MAs identified on SS-OCT slabs were correlated to MAs identified on FA. Results: MAs were identified in SS-OCT slabs in 15/17 eyes, resulting in NPDR diagnosis rate of 88%. Mean number of MAs identified on FA was 11.7±11.9 (total 199) and was 8.1±9.3 (total 137) on SS-OCT. Wilcoxon rank sum test showed no significant difference in MAs detected on SS-OCT and FA (P=0.2995) across eyes. Wilcoxon rank sum test showed SS-OCT detected slightly fewer MAs than FA per eye (3.65 less, P=0.0009). Conclusion: SS-OCT visualization of MAs could serve as a tool for diagnosing NPDR, and possibly applied as an imaging biomarker for population-based diabetic retinopathy screening. Keywords: diabetic retinopathy, swept-source optical coherence tomography, optical coherence tomography

Ruwan A Silva, Darius M Moshfeghi, Theodore Leng Byers Eye Institute at Stanford, Stanford University School of Medicine, Palo Alto, CA, USA Abstract: Ocriplasmin represents a new treatment option for numerous vitreoretinopathies involving an abnormal vitreomacular interface. While the drug may circumvent the traditional risks of surgical treatment, pharmacologic vitreolysis is not devoid of risk itself. This report presents two cases, one of vitreomacular traction syndrome and the other of a full-thickness macular hole, both of which were treated with an intravitreal injection of ocriplasmin. Notably, in both cases, vitreomacular traction of the macula appears to have been alleviated; however, failure to completely relieve vitreoretinal traction from the peripheral retina generated retinal breaks with one patient eventually developing a macula-involving retinal detachment. Thus, even in instances of ‘successful’ pharmacologic treatment of vitreomacular traction, continued follow-up evaluation is essential. Keywords: posterior vitreous detachment, retinal detachment, vitreomacular traction, ocriplasmin, retinal break, macular hole, laser retinopexy

Lingmin He, Annie Chan, Theodore Leng, Mark S BlumenkranzDepartment of Ophthalmology, Stanford University School of Medicine, Stanford, California, USABackground: The purpose of this study was to characterize central macular thickness and retinal volume following intravitreal injections using time domain and spectral domain optical coherence tomography (TD-OCT and SD-OCT, respectively).Methods: Nine patients with macular edema secondary to diabetes or retinal vein occlusion treated with intravitreal triamcinolone 4.0 mg and/or bevacizumab 1.25 mg were enrolled. Central macular thickness and volume was measured by SD-OCT and TD-OCT scan at baseline, and 1, 3, 6, 24, 48 hours, and 1 week postinjection.Results: Equations were derived to describe central macular thickness and volume reduction in the hours following intravitreal injection. Measurements of central macular thickness by SD-OCT were significantly reduced by 3 hours (P = 0.03) and retinal volume by 6 hours (P = 0.03). Central macular thickness measured 40.9 (28.6–53.2) µm thicker on the SD-OCT instrument while volume measured 3.47 (3.27–3.66) mm3 higher.Conclusion: Significant central macular thickness and volume reductions occur in the first hours after injection with triamcinolone and/or bevacizumab.Keywords: retinal vein occlusion, intravitreal injection, diabetic retinopathy

David J Jacobs, Theodore Leng, Harry W Flynn Jr, Wei Shi, Darlene Miller, Steven J GeddeDepartment of Ophthalmology, Bascom Palmer Eye Institute, Miller School of Medicine, University of Miami, FL, USAPurpose: To determine how culture results are associated with clinical presentations and outcomes in delayed-onset bleb-associated endophthalmitis (BAE).Methods: Retrospective consecutive case series of BAE at Bascom Palmer Eye Institute between January 1, 1996 and December 31, 2009. All patients had prior glaucoma filtering surgery. BAE was defined as intraocular infection with vitreous involvement receiving treatment with intravitreal antibiotics. Visual acuity (VA) outcomes and other clinical data were grouped by culture result and compared using the 2-sided Student's t-test.Main outcome measure: Mean logMAR change at 3 months after treatment (3-month logMARΔ).Results: Eighty-six eyes of 85 patients were identified. Two eyes were primarily eviscerated. Fifty-three (63%) eyes were culture-positive with the following organisms: Streptococcus, 21 (25%); coagulase-negative Staphylococcus, 9 (11%); Enterococcus, 6 (7%); Gram-negative, 15 (18%); Moraxella, 8 (10%); Pseudomonas, 3 (4%); and Serratia, 3 (4%). Presenting logMAR VA: culture-positive worse than culture-negative cases (2.45 vs 2.19, P = 0.05). Presenting intraocular pressure (IOP): culture-positive higher than culture-negative cases (24 mmHg vs 14 mmHg, P = 0.002). Poor presenting view of the fundus: Streptococcus worse than coagulase-negative Staphylococcus cases (90% vs 44%, P = 0.006), Pseudomonas and Serratia worse than Moraxella cases (100% vs 50%, P = 0.04). Three month logMARΔ: culture-positive worse than culture-negative cases (1.03 vs 0.43, P = 0.02), Streptococcus worse than coagulase-negative Staphylococcus cases (1.44 vs 0.31, P = 0.004), Pseudomonas and Serratia worse than coagulase-negative Staphylococcus cases (2.41 vs 0.31, P = 0.001), Pseudomonas and Serratia worse than Moraxella cases (2.41 vs 0.04, P = 0.001). A culture result of Streptococcus or Serratia was present in 6 of 7 eyes that received an additional treatment of enucleation or evisceration (P = 0.01).Conclusion: Culture-positive cases were associated with worse presenting VA, higher presenting IOP, and worse VA outcomes than culture-negative cases. Streptococcus, Pseudomonas, and Serratia cases were associated with poor presenting view of the fundus and worse VA outcomes than coagulase-negative Staphylococcus and Moraxella cases.Keywords: endophthalmitis, bleb-associated endophthalmitis, trabeculectomy, culture results

Theodore LengByers Eye Institute at Stanford, Stanford University School of Medicine, Palo Alto, CA, USAAbstract: Spectral domain optical coherence tomography was used to image the maculae of two brothers who had the diagnosis of X-linked retinoschisis maculopathy. One patient demonstrated a large foveal cyst in one eye and a lamellar macular hole in the fellow eye. The second patient demonstrated small retinal cysts in multiple layers of the retina. Spectral domain optical coherence tomography allowed high-resolution imaging and characterization of the features in X-linked retinoschisis in these patients, and it highlighted the variability of the same genetic disease, even in one family.Keywords: SD-OCT, XLRS, retina, imaging, maculopathy

Annie Chan, Douglas R Fredrick, Theodore Leng Department of Ophthalmology, Byers Eye Institute at Stanford University, Stanford University School of Medicine, Stanford, CA, USA Abstract: We report a case of neovascularization secondary to Purtscher's retinopathy that showed minimal improvement with photocoagulation treatment. A 14-year-old boy with a history of cerebellar medulloblastoma presented with blurry vision and floaters after being struck by a motor vehicle while riding his bike. At presentation, visual acuity was 20/400 in his right eye and counting fingers in his left eye. Fundus examination showed disk edema, retinal whitening, and retinal hemorrhages in both eyes. Optical coherence tomography demonstrated thinning of the temporal retina and disruption of the inner segment–outer segment junction of the photoreceptor layer in the right eye and thickening and edema of the nasal macula, as well as a central foveal hyper-reflectivity, in the left eye. At the initial visit, there was no ischemia or neovascularization (NV). One month later, the patient developed NV of the disk and ischemia in the mid-periphery of the left eye. The patient underwent treatment with pan-retinal photocoagulation. The NV regressed, but visual outcome remained poor at his 5-month follow-up visit. Keywords: Purtscher's retinopathy, neovascularization, laser photocoagulation, disk edema

Increasing oil production is crucial for multilayer co-production. When there are significant differences in the permeability of each layer, an interlayer contradiction arises that can impact the recovery efficiency. After a number of tests and the establishment of a mathematical model, the effects of permeability contrast on oil production for water flooding were revealed. In the meantime, the developed mathematical model was solved using the Buckley–Lever seepage equation. Ultimately, the accuracy of the established model was confirmed by comparing the simulated outcomes of the mathematical model with the experimental results. The findings indicate that when permeability contrast increases, the production ratio of the high-permeability layer will improve. This is primarily due to the low-permeability layer’s production contribution rate decreasing. The accuracy of the established model is ensured by an error of less than 5% between the results of the experiment and the simulation. When the permeability contrast is less than three, the low-permeability layer can be effectively used for three-layer commingled production. However, when the permeability contrast exceeds six, the production coefficient of the low-permeability layer will be less than 5%, which has a significant impact on the layer’s development.

Homogenization of pigment is the key to coloring a plastic product evenly. In this article, the tensile properties of recovered carbon black merge with low molecular weight lubricants and other compounding ingredients in the form of pigment masterbatch (PM) added in a recycled low-density polyethylene (rLDPE) resin were evaluated. The prepared masterbatch with the varying amount and types of processing aids (A and B) was first compounded using the heated two-roll mill. Subsequently, the manually mixed masterbatch in rLDPE was put through an injection molding machine for the shaping process to produce an rLDPE pigment masterbatch composite (PMC). The tensile test was performed on the samples to evaluate the mechanical properties of the PMC. Meanwhile, the melt flow index test was executed to justify the composite flow characteristics. Fourier-transform infrared spectroscopy analysis and scanning electron microscopy were also carried out to analyze the PM and PMC chemical properties and their constructed surface morphology. Besides, X-ray diffraction analysis was performed to determine the changes in degree of crystallinity before and after the water absorption test. The addition of PM in rLDPE has slightly increased the rLDPE matrix tensile properties. While, the usage of more processing aid B in the PMC has turned out to secure better tensile properties compared to the addition of higher amount of processing aid A in the PMC. Interestingly, the tensile properties of all composites after the water absorption test were enhanced, suggesting that a stronger bond was formed during the immersion period.

Understanding and manipulating geological pore structures is of paramount importance for geo-energy productions and underground energy storages in porous media. Nevertheless, research emphases for long time have been focused on understanding the pore configurations, while few work conducted to modify and restructure the porous media. This study deploys ultrasonic treatments on typical geological in-situ core samples, with follow-up processes of high-pressure mercury injections and nitrogen adsorptions and interpretations from nuclear magnetic resonance and x-ray diffraction. The core permeability and porosity are found to increase by 8.3 mD, from 4.1 to 12.4 mD, and by 0.95%, from 14.03% to 14.98%, respectively. Meanwhile, the number and size of the micro- and mesopore are increased with progressing of ultrasonic treatment, while those of the macropore decrease, which finally increase the permeability and porosity. The increase of micro- and mesopore number, from x-ray diffraction results, is attributed to the migration and precipitation of clay minerals caused through ultrasonic wave. The relocation of clay minerals also helps to improve the pore-throat connectivity and modify the micro-scale heterogeneity. Basically, this study reveals the characterizations of geological pore reconfigurations post-ultrasonic treatments and interprets the associated mechanisms, which provides guidance to manipulate the geological pores and be of benefit for further porous media use in science and engineering.

The aim of this paper was to provide suggestions for good sports training and to help primary and secondary school students to improve their physical and mental health. It was also discussed the impact of digital transformation on students' sports training. The authors used qualitative analysis, synthesis and inductive methods. They also used experimental testing methods and experience. The authors consider physical education as a prerequisite for the development of other aspects of education. They explain the benefits of sports by stating that primary and secondary school students who participate in sports have the following benefits: they are healthier, they avoid the effects of technology and bad habits, they make friends, have fun, build social confidence, interact socially and learn to deal with failure. In conclusion, primary and secondary school students can successfully and safely improve their overall health by participating in a well-supervised sport training. Trained fitness professionals play an essential role in ensuring proper technique, form, progression of exercises, and safety in this age group.

CO2 flooding can effectively enhance the recovery of low-permeability reservoirs and realize CO2 geological storage. During the displacement process, the minimum miscible pressure (MMP) of CO2 and oil is an important parameter that affects the displacement effect and storage efficiency. However, the microscopic pore-throat structure of low-permeability reservoirs has significant influences on the fluids and phase behaviors. This paper presented a method to determine the miscible state of CO2 flooding based on the microscopic pore-throat structure. Firstly, a physic model was established to quantitatively characterize the microscopic pore-throat structure. Secondly, taking into consideration the P-R equation of state, the gas-liquid equilibrium in the narrow pore-throat was calculated. On this basis, a MMP prediction model was established correspongdingly by considering the multi-stage contact and mass transfer of CO2-oil. Finally, the results obtained by the proposed model were compared with the experimental results of CO2 flooding, and then the model was applied to the actual reservoir to predict plane distribution of MMP. The curves of MMP distribution and pressure drawdown between wells were combined to determine the position of miscible front and non-miscible area at different production stages. The results have shown that the MMP of core sample calculated by the model was 20.3 MPa, which was comparable to that of CO2 flooding experiment, e.g., 20 MPa, and thus indicatesd a high accuracy of the model. The MMP in the well control area of the Y29-101 well group was 19.8 MPa. During the unsteady flow stage, the miscible-phase front was 430 m from the injection well, while it was 310 m from the injection well during the stable flow stage. This method can accurately determine the specific phase distribution of CO2-oil in the formation, which is of great significance to promote the development of CO2 flooding and storage technology, improve the recovery of low permeability reservoirs, ensure energy supply and reduce carbon emission.

At present, the main development mode of “horizontal well + volume fracturing” is adopted in a tight glutenite reservoir. Due to the existence of conglomerate, the seepage characteristics are more complex, and the production capacity after volume fracturing is difficult to predict. In order to solve this problem, a dual media unstable seepage model was established for matrix seepage and discrete fracture network seepage when considering the trigger pressure gradient. By considering the Poisson's ratio of stress sensitivity in an innovative way, the coupling model of permeability and stress is improved, and the production prediction model of volume fracturing horizontal well in a tight glutenite reservoir based on the fluid-solid coupling effect is formed. The finite element method is used to numerically solve the model, and the fitting verification of the model is carried out; the impact of stress sensitivity, producing pressure difference, fracture length, number of fracture clusters and fracture flow capacity conductivity on productivity is analyzed, which has certain guiding significance for the efficient development of volume fracturing in a tight glutenite reservoir.

The objective of this study is to analyze the role of gender in decision making in rural areas and to measure the level of equality between husband and wife in the family in rural Trieu Son district, Thanh Hoa province. The research results show that there are differences in decision-making in production management, income-generating production activities, and in developing household economic resources in terms of gender. The highest importance factors affecting this issue include gender and educational background.