72 results on '"Yuanbo Liang"'
Search Results
2. Acute angle-closure glaucoma before, during, and after the outbreak of COVID-19 in China
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Yu Mao, Yanqian Xie, Guoxing Li, Rongrong Le, Shuxia Xu, Peijuan Wang, Xiaojie Wang, Qi Zhang, Shaodan Zhang, and Yuanbo Liang
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Acute angle closure glaucoma ,Intraocular pressure ,COVID-19 ,Severe acute respiratory syndrome coronavirus disease 2 ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
Objectives: Acute angle-closure glaucoma (AACG) is a major cause of irreversible and severe visual function loss. Robust rise in AACG was observed in the ophthalmic outpatient clinics concomitant with the outbreak of COVID-19 infection in China after the relaxing of “zero-COVID policy” in early December 2022. Here we compared the demographic and clinical profiles of patients with AACG before, during and after the COVID-19 outbreak. Underlying mechanisms were tentatively investigated. Methods: This is a retrospective comparative study. Consecutive cases with newly diagnosed AACGs in a tertiary eye hospital were retrospectively collected during December 17, 2022 to January 8, 2023. Data from the same period in 2018–2019 and 2019–2020, 2020–2021 and 2021–2022, and 2023–2024 were collected as pre-pandemic, pandemic-control, and post-pandemic control, respectively. For the patients in 2022–2023 outbreak group, COVID-19 infection was confirmed by reversed transcriptase-polymerase chain reaction or antibody test for severe acute respiratory syndrome coronavirus disease 2 (SARS-CoV-2) from nasopharyngeal swabs. Ocular parameters, serum electrolytes and coagulative parameters were compared between COVID-19 positive and negative AACGs in observational group. SARS-CoV-2 nucleic acid in the aqueous humor was detected. Results: A total of 106 AACG cases were diagnosed during the outbreak period in 2022–2023. In contrast, 18 (in 2018–2019) and 22 (in 2019–2020) cases were included during pre-pandemic period, and 21 (in 2023–2024) during the post-pandemic period. Only 13 and 4 newly onset AACG were included in 2020–2021 and 2021–2022 during the pandemic-control period, respectively. Younger age and higher proportion of bilateral involvement were detected in COVID-19 outbreak group than that of other groups (p = 0.034 and p = 0.080). Sixty-eight (64.2 %) patients in the outbreak group had a confirmed COVID-19 infection. Intervals between infection and AACG attack was 52 ± 85h (0-15d). Fifty-three patients (77.9 %) reported the applications of ibuprofen or other antipyretic medications and 25 (36.8 %) reported large volume water intake before AACG attack. COVID-19-positive AACG patients had higher level of D-dimer than their negative counterparts (1.13 ± 2.60 mg/L vs. 0.46 ± 0.43 mg/L, p = 0.083). No difference in IOP, serum electrolytes, and coagulative parameters other than D-dimer was observed between COVID-19 positive and negative cases. SARS-CoV-2 were negative in the aqueous humor from 14 COVID-19 positive and 8 negative patients. Conclusion: COVID-19 infection surged the onset of AACG in patients at risk. Mental stress, water intake, increased choroidal thickness due to SARS-CoV-2 induced ACE receptor activation, and hyper-coagulation, may contribute to the disease onset. Ocular involvement should not be ignored in both routine and new systemic emergent conditions.
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- 2024
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3. Nanomedicine in glaucoma treatment; Current challenges and future perspectives
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Haroon Iqbal, Anam Razzaq, Dengming Zhou, Jiangtao Lou, Run Xiao, Fu Lin, and Yuanbo Liang
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Glaucoma ,Eye drops ,Ocular drug delivery ,Nanomedicine ,Sustained release ,Targeted treatment ,Medicine (General) ,R5-920 ,Biology (General) ,QH301-705.5 - Abstract
Glaucoma presents a significant global health concern and affects millions of individuals worldwide and predicted a high increase in prevalence of about 111 million by 2040. The current standard treatment involves hypotensive eye drops; however, challenges such as patient adherence and limited drug bioavailability hinder the treatment effectiveness. Nanopharmaceuticals or nanomedicines offer promising solutions to overcome these obstacles. In this manuscript, we summarized the current limitations of conventional antiglaucoma treatment, role of nanomedicine in glaucoma treatment, rational design, factors effecting the performance of nanomedicine and different types of nanocarriers in designing of nanomedicine along with their applications in glaucoma treatment from recent literature. Current clinical challenges that hinder real-time application of antiglaucoma nanomedicine are highlighted. Lastly, future directions are identified for improving the therapeutic potential and translation of antiglaucoma nanomedicine into clinic.
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- 2024
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4. Anterior chamber proliferative membrane interception (AC-PMI)-enhanced trabeculectomy versus trabeculectomy for treating neovascular glaucoma: protocol for a randomized controlled trial
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Shuqing Zhu, Mengtian Zhou, Haoyu Li, Shaodan Zhang, Shuxia Xu, Haishuang Lin, Yanqie Xie, Rongrong Le, and Yuanbo Liang
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Ophthalmology ,Neovascular glaucoma ,Surgery ,Medicine (General) ,R5-920 - Abstract
Abstract Background Neovascular glaucoma (NVG) is an irreversible blinding eye disease worldwide and is classified as one of the refractory glaucoma conditions, severely impacting visual function and vision. Unfortunately, effective surgical interventions to improve the prognosis of NVG patients are currently lacking. The study aims to evaluate the efficacy and safety of anterior chamber proliferative membrane interception (AC-PMI)-enhanced trabeculectomy compared to the traditional trabeculectomy. Methods AC-PMI enhanced trabeculectomy versus trabeculectomy for the treatment of NVG is a single-center, prospective, double-arms, and randomized controlled trial of superior efficacy, which will involve 100 NVG inpatients. Patients will be randomly assigned into two groups using the random number table method. One group will undergo trabeculectomy using anti-vascular endothelial growth factor (Anti-VEGF) preoperatively and mitomycin C intraoperatively, while the other group will undergo AC-PMI enhanced trabeculectomy with the same medications (Anti-VEGF and mitomycin C). The patients will be followed up at the baseline and 1 day, 1 week, 1 month, 3 months, 6 months, 12 months, 18 months, and 24 months postoperatively. Meanwhile, we will collect the demographics, characteristics, and examination results and monitor any occurrences of adverse events at each follow-up time. Discussion This is an efficacy study of a novel surgical approach for treating neovascular glaucoma. Building upon conventional filtering surgeries, this approach introduces an additional step involving the interception of the proliferative membrane to effectively halt the growth of fibrovascular tissue. This study aims to explore a promising new surgical approach for managing NVG and contribute to the advancement of glaucoma treatment strategies. Trial registration ChiCTR ChiCTR2200055138. Registered on 01 January 2022. https://www.chictr.org.cn/showproj.html?proj=145255.
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- 2024
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5. Trends in admission rates of primary angle closure diseases for the urban population in China, 2011–2021
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Qi Chen, Peng Shen, Mengtian Zhou, Yang Cao, Xuanli Zheng, Fengping Zhao, Haishuang Lin, Yutong Ding, Yiting Ji, Jingjing Zuo, Hongbo Lin, and Yuanbo Liang
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primary angle closure diseases ,cataract surgery ,laser peripheral iridotomy ,regional health big data ,trends ,Public aspects of medicine ,RA1-1270 - Abstract
BackgroundCataract surgery and laser peripheral iridotomy (LPI) are effective approaches for preventing primary angle closure diseases (PACDs), as well as acute primary angle closure (APAC). Due to the development of population screening and increases in cataract surgery rates, this study aimed to examine trends in the admission rates of PACD among the urban population in China.MethodsThis cross-sectional study examined patients who were admitted to a hospital for PACD, and who underwent cataract surgery or LPI operations. The data were obtained from the Yinzhou Regional Health Information Platform (YRHIP) from 2011 to 2021. The annual rates of PACD and APAC admissions, cataract surgery and LPI were analyzed, with the number of cases used as numerators and the annual resident population in Yinzhou district used as denominators.ResultsA total of 2,979 patients with PACD admissions, 1,023 patients with APAC admissions, 53,635 patients who underwent cataract surgery and 16,450 patients who underwent LPI were included. The number of annual admissions for PACD gradually increased from 22 cases (1.6/100000) in 2011 to 387 cases (30.8/100000) in 2016, after which it decreased to 232 cases (16.2/100000) in 2019 and then increased to 505 cases (30.6/100000) in 2021. The number of cataract surgeries gradually increased from 1728 (127.7/100000) in 2011 to 7002 (424.9/100000) in 2021. Similarly, the number of LPI gradually increased from 109 (8.0/100000) in 2011 to 3704 (224.8/100000) in 2021.ConclusionThe admission rates of PACD for the urban population in China have declined in recent years after a long increasing trend in the rates of cataract surgery and LPI. However, it increased rapidly during the COVID-19 epidemic. The national health database should be further utilized to investigate temporal trends in the prevalence of PACD.
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- 2024
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6. Ground Strength Test Technique of Variable-Camber Wing Leading Edge
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Shanshan Li, Xianmin Chen, Zhigang Wang, and Yuanbo Liang
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variable-camber wing ,leading edge ,motor function ,strength test ,cooperative loading ,morphological reconstruction ,Technology - Abstract
Morphing wing technology is crucial for enhancing the flight performance of aircraft. To address the monitoring challenges of full-scale variable-camber leading edges under flight conditions, this study introduces a ground-based strength testing technique aimed at precisely evaluating the deformation patterns and structural strength during actual operation. Firstly, the motion characteristics of the variable-camber leading edge were analyzed using numerical simulation based on kinematic theory. Secondly, a tracking loading test rig was designed and constructed to simulate the actuated deformation and aerodynamic loads of the leading edge. Next, mechanical boundary numerical simulation was then utilized to predict the motion trajectories of loading points on the upper and lower wing surfaces, and a multi-point coordinated control system was developed to achieve accurate experimental control. Finally, a multi-sensor iterative method was employed to ensure loading precision throughout the testing process. A case study was conducted using a leading edge test piece from a specific commercial aircraft. The results indicated that in the motion test of the variable-camber leading edge, the average error of the deflection angle was 4.59%; in the strength test, the average errors in the magnitude and direction of the applied load were 0.54% and 0.24%, respectively. These findings validate the effectiveness of the proposed technique in simulating the flight conditions of deforming wings and accurately obtaining the leading edge shape change curve, deformation accuracy curve, and strain curves of the upper and lower wing surfaces under deflection angles. Furthermore, this paper compares the deformation accuracy of different testing methods under test conditions, providing scientific evidence and technical support for the testing and evaluation of variable-camber leading edges.
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- 2024
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7. Associations between vision impairment and multimorbidity among older Chinese adults: results from the China health and retirement longitudinal study
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Kun Xiong, Huiyan Mao, Qi’ao Zhang, Changrong Lei, and Yuanbo Liang
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Vision impairment ,Multimorbidity ,Chronic conditions ,Low- and middle-income countries ,Elderly ,Geriatrics ,RC952-954.6 - Abstract
Abstract Background Although several studies have reported the relationship between vision impairment (VI) and multimorbidity in high-income countries, this relationship has not been reported in low- and middle-income countries. This study aimed to explore the relationship between VI with multimorbidity and chronic conditions among the elderly Chinese population. Methods The cross-sectional analysis was applied to data from the China Health and Retirement Longitudinal Study (CHARLS) in 2018. A total of 8,108 participants ≥ 60 years old were included, and 15 chronic conditions were used in this study. Logistic regression analysis was used to analyze the relationship between VI with multimorbidity and chronic conditions. Results The prevalence of 15 chronic conditions and multimorbidity was higher among the elderly with VI than those without VI. After adjusting for demographic and socioeconomic confounders, 10 chronic conditions were associated with VI (all P
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- 2023
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8. Impact of primary glaucoma on health-related quality of life in China: the handan eye study
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Di Song, Sujie Fan, Qiang Zhou, Xiaohui Yang, Sizhen Li, Lynne Lohfeld, Weihe Zhou, Nathan Congdon, Yuanbo Liang, and Ningli Wang
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Glaucoma ,EQ-5D ,Health-Related Quality of Life ,Visual function quality of life ,Ophthalmology ,RE1-994 - Abstract
Abstract Background We assessed health-related quality of life (HRQOL) and its determinants among rural glaucoma participants compared to age-matched normal controls in the population-based Handan Eye Study (HES), in rural Yongnian County, northern China. Methods We enrolled 99 adults with glaucoma (mean age 63.0 ± 11.0 years), including primary open-angle glaucoma (POAG, n = 67) and primary angle-closure glaucoma (PACG, n = 32) and 102 controls (mean age 58.5 ± 5.3 years) with normal visual acuity and visual field and no history of glaucoma. Results of ophthalmic examinations and socioeconomic data were recorded. HRQOL was measured using the EQ-5D (converted to utility valves, UVs), and visual function (VF) and vision-related quality of life (VRQOL) were evaluated using the visual function-quality of life (VF-QOL) instrument. Primary and secondary outcome measures EQ-5D and VF-QOL scores. Results The mean UVs, VF, and VRQOL scores for glaucoma cases were 0.98 ± 0.04, 87.9 ± 15.2, and 95.5 ± 12.8, respectively, significantly worse than VF (94.4 ± 4.4) and VRQOL (100.0 ± 0.0) among controls, even after adjusting for age, gender, educational level, and family income (P = 0.015, P = 0.033). UVs were significantly lower among glaucoma participants with impaired VRQOL (55.4 ± 11.5) compared to those with normal VRQOL scores (99.1 ± 2.8) (UVs: 0.92 ± 0.08 vs. 0.99 ± 0.03, P = 0.036), also after adjustment for age and family income (P = 0.006). Participants with PACG had significantly lower VF and VRQOL scores compared to POAG (77.8 ± 21.4 vs. 92.9 ± 6.8, P
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- 2023
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9. Incidence and characteristics of aqueous misdirection after glaucoma surgery in Chinese patients with primary angle-closure glaucoma
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Haishuang Lin, Jiaqian Li, Xuanli Zheng, Rui Wan, Mengtian Zhou, Yutong Ding, Yiting Ji, Yanqian Xie, Clement C. Tham, Shaodan Zhang, and Yuanbo Liang
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Incidence ,Aqueous misdirection ,Primary angle-closure glaucoma ,Glaucoma surgery ,Ophthalmology ,RE1-994 - Abstract
Abstract Background To report the incidence and clinical characteristics of aqueous misdirection (AM) after glaucoma surgery in Chinese patients with primary angle-closure glaucoma. Methods Medical records of all patients diagnosed with primary angle-closure glaucoma who underwent glaucoma surgery in the Eye Hospital of Wenzhou Medical University between January 2012 and December 2021 were retrospectively reviewed. Cases of AM were identified through a keyword-based search. The incidence of AM was calculated. Demographic and clinical characteristics of the AM patients were also described. Results A total of 5044 eyes with primary angle-closure glaucoma were included (mean age 65.81 ± 9.96 years, 68.11% women). Thirty-eight eyes developed AM, presenting an overall incidence of 0.75%. The mean time interval between surgery and first record of AM diagnosis was 2.57 ± 5.24 months (range, 0 day to 24 months). The incidence of AM was significantly higher in patients aged ≤ 40 years (21.28%) and those aged 40–50 years (3.32%), compared to those > 50 years (0.42%) (P
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- 2023
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10. Undiagnosed diabetic retinopathy in Northeast China: prevalence and determinants
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Bo Zang, Shisong Rong, Dong Li, Xiaoxia Ding, Dongxiao Zang, Fenghua Wang, Yuanbo Liang, Gang Zhai, Kemi Feng, Zixi Zhou, and Yu Wang
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diabetic retinopathy ,epidemiological investigation ,retinal screening ,public health ,vision ,Diseases of the endocrine glands. Clinical endocrinology ,RC648-665 - Abstract
ObjectiveTo report the prevalence and contributing factors of undiagnosed diabetic retinopathy (DR) in a population from Northeastern China.Subjects/MethodsA total of 800 subjects from the Fushun Diabetic Retinopathy Cohort Study were enrolled. A questionnaire assessing incentives and barriers to diagnosis of DR was administered. Logistic regression was used to identify clinical and sociodemographic factors associated with undiagnosed DR. In a prespecified subgroup analysis, we divided patients into vision-threatening diabetic retinopathy (VTDR) and non-VTDR (NVTDR) subgroups.ResultsAmong 800 participants with DR, 712 (89.0%) were undiagnosed. Among 601 with NVTDR, 566 (94.2%) were undiagnosed. Among 199 with VTDR, 146 (73.4%) were undiagnosed. The risk factors affecting the timely diagnosis of NVTDR and VTDR exhibit significant disparities. In multivariate models, factors associated with undiagnosed VTDR were age over 60 years (OR = 2.966; 95% CI = 1.205-7.299; P = 0.018), duration of diabetes over 10 years (OR = 0.299; 95% CI = 0.118-0753; P = 0.010), visual impairment or blindness (OR = 0.310; 95% CI = 0.117-0.820; P = 0.018), receiving a reminder to schedule an eye examination (OR = 0.380; 95% CI = 0.163-0.883; P = 0.025), and the belief that “people with diabetes are unlikely to develop an eye disease” (OR = 4.691; 95% CI = 1.116-19.724; P = 0.035). However, none of the factors were associated with undiagnosed NVTDR (all P ≥ 0.145).ConclusionOur research has uncovered a disconcerting trend of underdiagnosis in cases of DR within our population. Addressing determinants of undiagnosed DR may facilitate early detection.
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- 2023
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11. Quality assessment of non-mydriatic fundus photographs for glaucoma screening in primary healthcare centres: a real-world study
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Qi Chen, Yang Cao, Xiang Xu, Yuanbo Liang, Cong Ye, Junhong Jiang, Mengtian Zhou, Xuanli Zheng, Huiyan Mao, Changrong Lei, Wanglong Lin, Yize Chen, and Di Song
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Ophthalmology ,RE1-994 - Abstract
Background This study assessed the quality distribution of non-mydriatic fundus photographs (NMFPs) in real-world glaucoma screening and analysed its influencing factors.Methods This cross-sectional study was conducted in primary healthcare centres in the Yinzhou District, China, from 17 March to 3 December 2021. The quality distribution of bilateral NMFPs was assessed by the Digital Reading Department of the Eye Hospital of Wenzhou Medical University. Generalised estimating equations and logistic regression models identified factors affecting image quality.Results A total of 17 232 photographs of 8616 subjects were assessed. Of these, 11.9% of images were reliable for the right eyes, while only 4.6% were reliable for the left eyes; 93.6% of images were readable in the right eyes, while 90.3% were readable in the left eyes. In adjusted models, older age was associated with decreased odds of image readability (adjusted OR (aOR)=1.07, 95% CI 1.06~1.08, p
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- 2023
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12. Vision-related quality of life in patients with glaucoma: the role of illness perceptions
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Qiqi Zhang, Wenzhe Zhou, Di Song, Yanqian Xie, Hao Lin, Youping Liang, Yanhan Ren, Yuanbo Liang, and Yanyan Chen
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Glaucoma ,Vision-related quality of life ,Illness perceptions ,Common sense model ,Computer applications to medicine. Medical informatics ,R858-859.7 - Abstract
Abstract Purpose To explore the predictive effects of illness perceptions on vision-related quality of life (VRQoL) in Chinese glaucoma patients. Methods In this cross-sectional study, 97 patients with glaucoma completed the brief illness perception questionnaire (BIPQ), the glaucoma quality of life-15 (GQL-15) questionnaire, and a questionnaire regarding sociodemographic and clinical information. A correlation analysis and hierarchical linear regression analysis were performed. Results The BIPQ total score was positively correlated with the total score of the GQL-15 questionnaire and the scores of its four dimensions. Chronic comorbidities, the type of glaucoma, the best-corrected visual acuity (BCVA), the mean defect (MD) of visual field in the better eye, and identity in the BIPQ were critical predictors of VRQoL. Illness perceptions independently accounted for 7.8% of the variance in the VRQoL of glaucoma patients. Conclusions Patients with stronger illness perceptions and those who perceive themselves as having more glaucoma symptoms are likely to experience worse VRQoL. Illness perceptions in glaucoma patients deserve clinical attention, and further studies are needed to examine whether cognitive interventions targeting illness perceptions can improve VRQoL.
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- 2022
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13. China Glaucoma Treatment Pattern Study I–Primary Angle-Closure Glaucoma: protocol for a multicentre, retrospective, observational study
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Xin Sun, Dan Wang, Mingguang He, Li Tang, Yuanbo Liang, Jie Du, Wenyi Guo, Peng Lv, Zhengzheng Wu, Jianjun Ma, Jian Jiang, Jinyuan Chen, Xiaoli Xing, Danyan Liu, Zhiyang Jia, Yajuan Zheng, Guoping Duan, and Yihua Zhu
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Medicine - Abstract
Introduction Primary angle-closure glaucoma (PACG) is a leading cause of irreversible blindness globally, and the number of patients with PACG rises every year. Yet, there is a lack of knowledge about the clinical characteristics, therapeutic options and profile of patients with PACG in China. Hence, we design the China Glaucoma Treatment Pattern Study Ⅰ–Primary Angle-Closure Glaucoma (Ch-GTPⅠ). The objective of this paper is to describe the design and methodology of Ch-GTP. The aim of this study is to characterise the profile and trend associated with initial PACG treatment for the last 10 years in China.Methods Ch-GTPⅠ is a national multicentre retrospective observational study that will randomly sample from 50 hospitals throughout China. Over 7000 patient records hospitalised for initial PACG treatment from 2011 to 2020 will be selected randomly. The data from electronic medical records will be uploaded to an encrypted online platform that will receive and collate data from all collaborating hospitals. Data abstraction and monitoring will be performed in a standardised manner by trained statisticians to ensure consistency. Systematic data cleaning will also be conducted by statisticians to ensure data integrity before final data storage. The outcomes will include four broad categories: (1) demographics, (2) clinical characteristics, (3) therapeutic strategies and procedures and (4) early outcomes at discharge. The demographic characteristics and early outcomes will be summarised using descriptive statistics. Comparative analyses of characteristics and treatment pattern changing trends for different regions and years will be used to test for significant differences (t-test or Mann-Whitney U test).Ethics and dissemination The collaborating hospitals obtained local approval based on a standard ethics application from internal ethics committees or acknowledged an existent ethics approval of the leading institution with approval from internal ethics committees. Due to the retrospective nature, written informed consent from patients was waived by the ethics committee. The results will be published in academic journals and presented at national and international academic conferences.Trial registration number ChiCTR2100054643.
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- 2023
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14. Metformin protects trabecular meshwork against oxidative injury via activating integrin/ROCK signals
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Lijuan Xu, Xinyao Zhang, Yin Zhao, Xiaorui Gang, Tao Zhou, Jialing Han, Yang Cao, Binyan Qi, Shuning Song, Xiaojie Wang, and Yuanbo Liang
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open-angle glaucoma ,trabecular meshwork ,cytoskeleton remodelling ,metformin ,Medicine ,Science ,Biology (General) ,QH301-705.5 - Abstract
This study aimed to investigate the protective effect of metformin on trabecular meshwork (TM) and explore its molecular mechanisms in vivo and in vitro. Ocular hypertension (OHT) mouse models were induced with dexamethasone and further treated with metformin to determine the intraocular pressure (IOP)-lowering effect. Cultured human TM cells (HTMCs) were pre-stimulated with tert-butyl hydroperoxide (tBHP) to induce oxidative damage and then supplemented with metformin for another 24 hr. The expression of fibrotic markers and integrin/Rho-associated kinase (ROCK) signals, including α-smooth muscle actin (α-SMA), transforming growth factor-β (TGF-β), fibronectin, integrin beta 1, ROCK 1/2, AMP-activated protein kinase, myosin light chain 1, and F-actin were determined by western blotting and immunofluorescence. Reactive oxygen species (ROS) content was analysed using flow cytometry. Transmission electron microscopy was performed to observe microfilaments in HTMCs. It showed that metformin administration reduced the elevated IOP and alleviated the fibrotic activity of aqueous humour outflow in OHT models. Additionally, metformin rearranged the disordered cytoskeleton in the TM both in vivo and in vitro and significantly inhibited ROS production and activated integrin/ROCK signalling induced by tBHP in HTMCs. These results indicated that metformin reduced the elevated IOP in steroid-induced OHT mouse models and exerted its protective effects against oxidative injury by regulating cytoskeleton remodelling through the integrin/ROCK pathway. This study provides new insights into metformin use and preclinical evidence for the potential treatment of primary open-angle glaucoma.
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- 2023
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15. Intraocular asymmetry of visual field defects in primary angle-closure glaucoma, high-tension glaucoma, and normal-tension glaucoma in a Chinese population
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Junhong Jiang, Cong Ye, Cong Zhang, Wenqing Ye, Xiaoyan Wang, Xiao Shang, Xiang Xu, Hongte Zhang, Shaodan Zhang, Jingwei Zheng, Jingjing Zuo, Jingjing Hu, Nathan Congdon, Fan Lu, and Yuanbo Liang
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Medicine ,Science - Abstract
Abstract Direct comparison data on spatial patterns of visual field (VF) defects among primary angle-closure glaucoma (PACG), high-tension glaucoma (HTG) and normal-tension glaucoma (NTG) are not available. We aimed to compare the intraocular asymmetry of VF loss among patients with PACG, NTG and HTG across different severity levels. A total of 162 eyes of 114 patients with PACG, 111 eyes of 74 patients with HTG and 148 eyes of 102 patients with NTG were included. VF defects were categorized into 3 stages (early, moderate, and advanced), and each hemifield was divided into 5 regions according to the Glaucoma hemifield test (GHT). The mean total deviation (TD) of each GHT region was calculated. In the early stage, the paracentral, peripheral arcuate 1 and peripheral arcuate 2 regions in the superior hemifield in the NTG group had significantly worse mean TDs than their corresponding regions in the inferior hemifield. In the advanced stage, the central region in the superior hemifield in the PACG group had a significantly worse mean TD than that in the inferior hemifield. There was no significant difference in the mean TD for any of the five regions between hemifields across all severity levels in the in the HTG group. The superior hemifield was affected more severely than the inferior hemifield in all three subtypes of primary glaucoma. This asymmetric tendency was more pronounced in NTG than in PACG and HTG.
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- 2021
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16. Evening exercise is associated with lower odds of visual field progression in Chinese patients with primary open angle glaucoma
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Xiafei Pan, Kai Xu, Xin Wang, Guofu Chen, Huanhuan Cheng, Alice Jia Liu, Laurence Tang Hou, Lin Zhong, Jie Chen, and Yuanbo Liang
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Glaucoma ,Exercise habits ,Visual field progression ,Ophthalmology ,RE1-994 - Abstract
Abstract Background Exercise is widely known to lower intraocular pressure and increase ocular blood flow, which may be beneficial for glaucoma management. However, there are few studies that have reported on the relationship between exercise and glaucoma progression. The aim of our study was to investigate the exercise habits of those with primary open angle glaucoma (POAG) and its association with the progression of visual field (VF) loss. Methods Daily physical activity (PA) was monitored by an accelerometer (ActiGraph wGT3x-BT) which patients wore for more than 10 h of being awake on their right wrists for 1 week. Results Seventy-one non-progressive and 27 progressive patients were enrolled in the study. 24-h moderate to vigorous physical activity (MVPA) exercise showed that POAG patients had similar variation trends consisting of 3 wave peaks and 2 wave hollows. Minutes spent in MVPA was 19.89 ± 15.81 and 21.62 ± 15.10 during 07:00–09:00 h (p = 0.204), 15.40 ± 14.49 and 15.67 ± 12.43 during 15:00–17:00 h (p = 0.822) and 17.26 ± 21.11 and 11.42 ± 11.58 during 18:00–20:00 h (p = 0.001) in the non-progressive and progressive group, respectively. Univariate analysis indicated that 10 min of MVPA (18:00–20:00 h) [odds ratio, OR (95% CI) = 0.82 (0.73, 0.92)], average mean arterial pressure [OR (95% CI) = 0.96 (0.94, 0.98)], age [OR (95% CI) = 1.06 (1.03, 1.08)], male [OR (95% CI) = 0.67 (0.48, 0.96)], spherical equivalent [OR (95% CI) = 1.14 (1.07, 1.22)] and IOP-lowering medications [OR (95% CI) = 1.54 (1.16, 2.05)] were significantly correlated with having progressive VF damage. Multivariable analysis showed that 10 min of MVPA (18:00–20:00 h) [OR (95% CI) = 0.85 (0.75, 0.97)] was associated with progressive VF loss even after adjusting for other risk factors. Conclusions Evening exercise may lower the odds of VF progression, suggesting that exercise habits possibly play an important role in glaucoma progression.
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- 2020
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17. Design and baseline data of a population-based metabonomics study of eye diseases in eastern China: the Yueqing Ocular Diseases Investigation
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Yuxuan Deng, Yuanbo Liang, Sigeng Lin, Liang Wen, Jin Li, Yue Zhou, Meixiao Shen, Jingwei Zheng, Kemi Feng, Yanting Sun, Kwapong Willaim Robert, Jia Qu, and Fan Lu
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Population ,Baseline ,Ophthalmic epidemiology ,Visual impairment ,Screening ,Metabonomics ,Ophthalmology ,RE1-994 - Abstract
Abstract Background China is undergoing a massive transition toward an urban and industrial economy. These changes will restructure the demographics and economy which will eventually influence the future patterns of disease. The risk factors of vision-impairing eye diseases remain ambiguous and poorly understood. Metabolomics is an ideal tool to understand and shed light on the ocular disease mechanisms for earlier treatment. This article aims to describe the design, methodology and baseline data of the Yueqing Ocular Diseases Investigation (YODI), a developed county population-based study to determine the prevalence and primary causes of visual impairment; also with metabonomics analysis we aimed to identify, predict and suggest some preventive biomarkers that cause blindness. Methods A population-based, cross-sectional study. Randomized clustering sampling was used to identify adults aged 50 years and older in Xiangyang Town, Yueqing county-level City. The interviews covered demographic, behavioral, ocular risk factors and mental health state. The ocular examination included visual acuity, autorefraction, intraocular pressure, anterior and posterior segment examinations, fundus photography, retinal tomography and angiography, and visual field testing. Anthropometric measurements included height and weight, waist and hip circumference, blood pressure, pulse rate, electrocardiogram, and abdominal ultrasound scan. A venous blood sample was collected for laboratory tests and metabonomics studies. Results Of the 5319 individuals recruited for the YODI, 4769 (89.7%) subjects were enrolled for analyses. The median age was 62.0 years, and 45.6% were male. The educational level of illiteracy or semi-illiteracy, primary, middle and high school or above was 29.8%, 45.5%, 20.1%, and 3.3%, respectively. Majority of the participants were female, younger, and less educated when compared with nonparticipants. The average body mass index and waist-hip ratios were 24.4 ± 3.4 kg/m2 and 0.9 ± 0.1 respectively. Blood sample collection reached a sample size of 1909 (479 from subjects with self-reported diabetes and 1430 from one-third of the 4290 subjects without self-reported diabetes). Conclusions The YODI provides population-based data with a high response rate (89.7%) on the prevalence and primary causes of major vision-impairing eye diseases in developed county areas in eastern China. Metabonomics analysis from YODI will provide further association of metabolic characteristics with the visual impairment eye diseases. The risk prediction model could be created and has the potential to be generalized to developed eastern areas in China for prevention.
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- 2020
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18. Improving Access to Refractive Services in Adults: A Health Examination Center-Based Model
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Haishuang Lin, Jing Sun, Nathan Congdon, Meiping Xu, Shanshan Liu, Yuanbo Liang, Hailin Wang, and Shaodan Zhang
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uncorrected refractive error ,spectacle coverage ,opportunistic screening ,health examination center ,refractive service ,Medicine (General) ,R5-920 - Abstract
Purpose: To assess the potential of a health examination center-based screening model in improving service for uncorrected refractive error.Methods: Individuals aged ≥18 years undergoing the routine physical examinations at a tertiary hospital in the northeast China were invited. Presenting visual acuity, noncycloplegic autorefraction, noncontact tonometry, fundus photography, and slit-lamp examination were performed. Refractive error was defined as having spherical equivalent ≤ -0.75 D or ≥ +1 D and uncorrected refractive error was considered as refractive error combined with presenting visual acuity < 6/12 in the better eye. Costs for the screening were assessed.Results: A total of 5,284 participants (61 ± 14 years) were included. The overall prevalence of myopia and hyperopia was 38.7% (95% CI, 37.4–40.0%) and 23.5% (95% CI, 22.3–24.6%), respectively. The prevalence of uncorrected refractive error was 7.85% (95% CI, 7.13–8.58%). Women (p < 0.001 and p = 0.003), those with age ≥ 70 years (p < 0.001 and p = 0.003), and myopia (p < 0.001 and p < 0.001) were at higher risk of uncorrected refractive error and uncorrected refractive error-related visual impairment. Spectacle coverage rate was 70.6% (95% CI, 68.2–73.0%). The cost to identify a single case of refractive error and uncorrected refractive error was US$3.2 and US$25.2, respectively.Conclusion: The prevalence of uncorrected refractive error is high in the urban Chinese adults. Health examination center-based refractive error screening is able to provide an efficient and low-cost model to improve the refractive services in China.
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- 2021
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19. Macula Structure and Microvascular Changes in Recent Small Subcortical Infarct Patients
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Yungang Cao, Jueyue Yan, Zhenxiang Zhan, Yuanbo Liang, and Zhao Han
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recent small subcortical infarcts ,macular capillaries ,retina ,capillary densities ,optical coherence tomography angiography ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Purpose: This study aimed to assess the macula structure and capillaries in the macula and optic nerve head in recent small subcortical infarct (RSSI) patients.Methods: This observational cross-sectional study included 40 RSSI patients and 46 healthy controls. Optical coherence tomography angiography was used to image the capillaries in the macula and optic nerve head. An inbuilt algorithm was used to measure the densities in the microvasculature of the macula [superficial retinal capillary plexus (SRCP) and deep retinal capillary plexus (DRCP)] and optic nerve head [radial peripapillary capillary (RPC)] and thickness around the optic nerve head, peripapillary retinal nerve fiber layer (pRNFL).Results: Densities in RPC (P < 0.001), SRCP (P = 0.001), and DRCP (P = 0.003) were reduced in RSSI patients when compared with healthy controls. The pRNFL thickness was thinner (P < 0.001) in RSSI patients than healthy controls. In the RSSI group, the SRCP density significantly correlated with the DRCP density (rho = 0.381, P = 0.042). The pRNFL thickness displayed a significant relationship with the RPC density (rho = 0.482, P = 0.003) in the RSSI group.Conclusions: RSSI patients showed interrupted capillary plexuses leading to its significant impairment and neurodegeneration. Our report provides insight into the macula capillary microcirculation changes in RSSI.
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- 2021
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20. Cost-effectiveness and cost-utility of population-based glaucoma screening in China: a decision-analytic Markov model
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Jianjun Tang, PhD, Yuanbo Liang, ProfMD, Ciaran O'Neill, ProfPhD, Frank Kee, ProfMD, Junhong Jiang, MD, and Nathan Congdon, ProfMD
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Public aspects of medicine ,RA1-1270 - Abstract
Summary: Background: Glaucoma, particularly primary angle closure glaucoma (PACG), is a leading cause of global blindness. Nearly half of all people with PACG are of Chinese descent. Population-level glaucoma screening has generally not been found to be cost-effective in high-income countries; however, this assessment has rarely been done in low-income or middle-income countries. We aimed to assess the cost-effectiveness and cost-utility of population-level glaucoma screening in China. Methods: We developed decision-analytic Markov models for separate and combined screening for PACG and primary open angle glaucoma (POAG) to evaluate costs and benefits of community-level screening versus opportunistic case finding from a societal perspective. A cohort of individuals was followed in the model from age 50 years through a total of 30 1-year Markov cycles. Analyses were done separately for rural and urban settings. We did a meta-analysis of glaucoma prevalence studies in China to obtain prevalence estimates for PACG and POAG. Screening costs were taken from a Chinese screening programme and treatment costs from a tertiary Chinese eye hospital. Main outcomes were incremental cost-utility ratios (ICURs) using quality-adjusted life-years and incremental cost-effectiveness ratios (ICERs) using years of blindness avoided. We did one-way deterministic and simulated probabilistic sensitivity analyses to reflect uncertainty around ICURs and ICERs. Findings: Compared with no screening, combined screening of POAG and PACG in rural China is predicted to result in an ICUR of US$569 (95% CI 17 to 4180) and an ICER of $1280 (−58 to 7940), both of which are below the WHO cost-effectiveness threshold of one to three times rural gross domestic product. For the urban China setting, combined screening is predicted to result in fewer net costs and greater gain in health benefits than no screening. Findings were robust in all sensitivity analyses. Over 30 years, a total of 246 (95% CI 63 to 628) and 1325 (510 to 2828) years of blindness are predicted to be avoided for every 100 000 rural and urban residents screened, respectively. Interpretation: Population screening for glaucoma (POAG and PACG combined) is likely to be cost-effective in both urban and rural China. Future studies should investigate the effectiveness of interventions to improve acceptance of definitive care among people screened. Funding: Ulverscroft Foundation, Wenzhou Medical University Research Fund, Zhejiang Province Health Innovation Talents Project, and Wenzhou's Ten Major Livelihood Issues 2015.
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- 2019
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21. Fresh fruit consumption and risk of incident albuminuria among rural Chinese adults: A village-based prospective cohort study.
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Jiangping Wen, Jie Hao, Ye Zhang, Yuanbo Liang, Sizhen Li, Fenghua Wang, Xinrong Duan, Xiaohui Yang, Kai Cao, Bingsong Wang, Xinxin Lu, and Ningli Wang
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Medicine ,Science - Abstract
BACKGROUND:Recent studies showed that increased fresh fruit consumption is significantly associated with lower risks of diabetes, hypertension, and cardiovascular disease (CVD); other studies suggested that albuminuria is associated with diabetes, hypertension, and CVD. Therefore, we hypothesized that lower fresh fruit consumption is associated with higher risk of incident albuminuria among Chinese adults in rural areas, where fresh fruit consumption level is very low and prevalence of albuminuria is high. METHODS:We tested the hypothesis in a village-based cohort study of 3574 participants aged ≥ 30 years from the Handan Eye Study conducted from 2006 to 2013. Albuminuria was defined as urinary albumin-to-creatinine ratio ≥ 30 mg/g. RESULTS:Overall, 35.4% of the participants never or rarely consumed fresh fruits, and 33.9, 21.6, and 9.1% consumed fresh fruits 1-3 times/month, 1-2 times/week, and ≥ 3 times/week, respectively. During a median follow-up period of 5.6 years, albuminuria developed in 17.6% (n = 629) of the participants. Compared with participants who consumed fresh fruits ≥ 3 times/week, the multivariable adjustment odds ratios (ORs) for incident albuminuria associated with fruit consumption 1-2 times/week, 1-3 times/month, and no or rare consumption were 1.58 (95% confidence intervals (CI), 1.05-2.40), 1.74 (95% CI, 1.17-2.58), and 1.78 (95% CI, 1.20-2.64), respectively. After excluding participants with diabetes, the association remained significant. CONCLUSIONS:Lower fresh fruit consumption was significantly associated with higher risk of incident albuminuria, and fresh fruit consumption frequency could be an essential intervention target to prevent albuminuria in rural China.
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- 2018
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22. A non-invasive risk score for predicting incident diabetes among rural Chinese people: A village-based cohort study.
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Jiangping Wen, Jie Hao, Yuanbo Liang, Sizhen Li, Kai Cao, Xilin Lu, Xinxin Lu, and Ningli Wang
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Medicine ,Science - Abstract
To develop a new non-invasive risk score for predicting incident diabetes in a rural Chinese population.Data from the Handan Eye Study conducted from 2006-2013 were utilized as part of this analysis. The present study utilized data generated from 4132 participants who were ≥30 years of age. A non-invasive risk model was derived using two-thirds of the sample cohort (selected randomly) using stepwise logistic regression. The model was subsequently validated using data from individuals from the final third of the sample cohort. In addition, a simple point system for incident diabetes was generated according to the procedures described in the Framingham Study. Incident diabetes was defined as follows: (1) fasting plasma glucose (FPG) ≥ 7.0 mmol/L; or (2) hemoglobin A1c (HbA1c) ≥ 6.5%; or (3) self-reported diagnosis of diabetes or use of anti-diabetic medications during the follow-up period.The simple non-invasive risk score included age (8 points), Body mass index (BMI) (3 points), waist circumference (WC) (7 points), and family history of diabetes (9 points). The score ranged from 0 to 27 and the area under the receiver operating curve (AUC) of the score was 0.686 in the validation sample. At the optimal cutoff value (which was 9), the sensitivity and specificity were 74.32% and 58.82%, respectively.Using information based upon age, BMI, WC, and family history of diabetes, we developed a simple new non-invasive risk score for predicting diabetes onset in a rural Chinese population, using information from individuals aged 30 years of age and older. The new risk score proved to be more optimal in the prediction of incident diabetes than most of the existing risk scores developed in Western and Asian countries. This score system will aid in the identification of individuals who are at risk of developing incident diabetes in rural China.
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- 2017
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23. Comparisons of different metabolic syndrome definitions and associations with coronary heart disease, stroke, and peripheral arterial disease in a rural Chinese population.
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Jiangping Wen, Jingang Yang, Yujie Shi, Yuanbo Liang, Fenghua Wang, Xinrong Duan, Xilin Lu, Qiushan Tao, Xinxin Lu, Yaping Tian, and Ningli Wang
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Medicine ,Science - Abstract
We estimated the prevalence of metabolic syndrome (MetS) and compared associations of different MetS definitions with coronary heart disease (CHD), stroke, and peripheral arterial disease (PAD) in a rural Chinese population.Among 4,748 residents (2,145 men and 2,603 women) aged 30+ years in rural China from 2006 to 2007, the prevalence of MetS was estimated by using five different definitions: modified World Health Organization (WHO), Chinese Diabetes Society (CDS), the updated National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATP III) for Asian-Americans, International Diabetes Federation (IDF), and Joint Interim Statement (JIS). Multivariable logistic regression analyses were implemented to estimate the association between MetS and the prevalence of CHD, stroke and PAD, respectively.Prevalence of MetS in men was 11.5% (WHO), 14.8% (CDS), 32.4% (NCEP-ATP III), 27.5% (IDF) and 39.7% (JIS) and in women was 15.7% (WHO), 20.7% (CDS), 54.2% (NCEP-ATP III), 51.5% (IDF) and 54.2% (JIS), respectively. Respective ORs (95% CI) for associating MetS with CHD in men were 1.79 (1.02-3.17), 1.25 (0.69-2.26), 1.61 (1.01-2.58), 1.84 (1.14-2.96), and 1.53 (0.96-2.43). Corresponding ORs (95% CI) for stroke in men were 2.18 (95% CI 1.20 to 3.97), 2.20 (95% CI 1.25 to 3.89), 1.71 (95% CI 1.02 to 2.84), 1.30 (95% CI 0.77 to 2.23), and 1.61 (95% CI 0.97 to 2.68), respectively. In women, CHD and stroke were significantly associated with MetS using all five definitions of MetS. In addition, PAD was associated with all five MetS definitions in men, but not in women. Only hyperglycemia and BMI were significantly associated with PAD in women.In this rural Chinese population, the JIS, IDF and CDS criteria may not be more suitable than WHO and updated NCEP-ATPIII definitions for screening high-risk individuals and estimating the risk of CHD and stroke from MetS, especially in men.
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- 2015
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24. Decreased macular deep capillary plexus is associated with functional progression of normal tension glaucoma patients with unilateral visual field loss.
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Sigeng Lin, Xiao Shang, Xiaoyan Wang, Xizhong Chu, Chengju Hu, Yuqing Si, De-fu Chen, Weihe Zhou, Yu Xiang George Kong, and Yuanbo Liang
- Abstract
Purpose To investigate whether quantitative optical coherence tomography angiography (OCTA) metrics of the superficial/deep macular retina are associated with the development of visual field (VF) loss in the fellow eyes of normal tension glaucoma (NTG) patients with unilateral VF loss. Methods A longitudinal study was conducted in which 61 eyes with normal VF (mean VF mean deviation -0.7±1.6 dB) from 61 NTG patients were included. All subjects underwent OCTA imaging, spectral-domain-OCT imaging and VF testing. OCTA metrics of superficial capillary plexus and deep capillary plexus (DCP) in the macular region were measured. Relationships between baseline OCTA metrics, demographics and ocular characteristics and the risk of VF glaucoma progression were analysed with a Cox proportional hazards model. Results During a mean follow-up of 38 months, 11 fellow eyes (18.0%) with normal VF at baseline were determined to have VF progression, while 21.3% of affected eyes had VF progression. After adjustment for potential confounding factors, decreased baseline DCP in the fellow eyes was significantly associated with future VF progression (HR 1.33, 95% CI 1.03 to 1.73, p=0.031). Conclusion Decreased DCP was associated with a higher risk of developing VF damage in NTG patients with unilateral VF loss. Assessments of DCP may help improve the evaluation of the risk of functional deterioration in fellow eyes with an initially normal VF. [ABSTRACT FROM AUTHOR]
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- 2024
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25. Incidence and risk factors of early transient intraocular pressure elevation after canaloplasty for primary open-angle glaucoma
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Lijuan Xu, Xinyao Zhang, Yang Cao, Yin Zhao, Juan Gu, Wenqing Ye, Xiaojie Wang, Jinxin Li, Ruiyi Ren, and Yuanbo Liang
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General Veterinary ,Correspondence ,General Medicine ,General Pharmacology, Toxicology and Pharmaceutics ,General Biochemistry, Genetics and Molecular Biology - Abstract
为分析原发性开角型青光眼(primary open-angle glaucoma,POAG)黏小管成形术后早期短暂性高眼压的发生率及危险因素,本研究纳入了本院顺利完成360°黏小管成形术的POAG患者。我们收集了以下数据:术后各随访时间点眼压(intraocular pressure,IOP),术后早期是否发生短暂性高眼压(定义:术后1周至3月内IOP>21 mmHg但能回落至≤21 mmHg)及术后一周最低IOP(IOP(min-1w))。根据是否发生术后早期短暂性高眼压,将其分为正常眼压组(normal IOP,NIOP)和短暂性高眼压组(high IOP,HIOP)。此外,我们也对术后早期短暂性高眼压的相关危险因素进行了分析。最终来自57位患者的57只眼纳入分析。他们的平均视野缺损值(mean defect, MD)为(-15.57±10.13) dB,IOP由术前 (29.43±10.27) mmHg显著降低至术后1年的(14.73±3.60) mmHg(P
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- 2023
26. Incidence, progression and regression of diabetic retinopathy in a northeastern Chinese population.
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Zhong Lin, Liang Wen, Yu Wang, Dong Li, Gang Zhai, Moonasar, Nived, Fenghua Wang, and Yuanbo Liang
- Abstract
Aim To determine the incidence, progression and regression of diabetic retinopathy (DR), with corresponding risk factors, in a northeastern Chinese population of patients with type 2 diabetes. Methods Among 2006 patients who completed baseline examinations in 2012–2013 and underwent re-examination after a mean interval of 21.2 months, 1392 patients with gradable fundus photographs for both baseline and follow-up examinations were included. Incidence was defined as new development of any DR among patients without DR at baseline. An increase of ≥2 scales (concatenating Early Treatment Diabetic Retinopathy Study levels of both eyes) in eyes with DR at baseline was defined as progression, while a reduction of ≥2 scales was defined as regression. Results The age- and sex-standardised incidence, progression and regression were 5.8% (95% CI 4.7% to 6.9%), 26.8% (95% CI 24.8% to 28.8%) and 10.0% (95% CI 8.6% to 11.3%), respectively. In addition to poor blood glucose control, wider central retinal venular equivalent was associated with both incidence (relative risk (RR) 2.17, 95% CI 1.09 to 4.32, for ≥250 µm vs <210 µm) and progression (RR 2.00, 95% CI 1.02 to 3.96, for ≥250 µm vs <210 µm). Patients without insulin therapy (RR 0.64, 95% CI 0.43 to 0.97) and patients with wider central retinal arteriolar equivalent (RR 1.14, 95% CI 1.02 to 1.26, per 10 µm increase) were likely to exhibit DR regression. Conclusion We determined the incidence, progression and regression of DR among northeastern Chinese patients with type 2 diabetes. Retinal vessel diameters, in addition to blood glucose level, influence the natural evolution of DR. [ABSTRACT FROM AUTHOR]
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- 2023
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27. Clinical outcomes of penetrating canaloplasty in patients with traumatic angle recession glaucoma: a prospective interventional case series.
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Huanhuan Cheng, Wenqing Ye, Shaodan Zhang, Yanqian Xie, Juan Gu, Rongrong Le, Yuxuan Deng, Cheng Hu, Zhenquan Zhao, Zhisheng Ke, and Yuanbo Liang
- Abstract
Background/aim To evaluate the clinical outcomes of penetrating canaloplasty in traumatic angle recession glaucoma at 1 year. Methods Patients with angle recession glaucoma underwent penetrating canaloplasty, a new Schlemm's canal-based internal drainage procedure, which creates a direct canal for flow of aqueous humour from the anterior chamber to the ostia of Schlemm's canal via a window created at the corneal scleral bed without use of antimetabolites. Postoperative intraocular pressure (IOP), number of glaucoma medications, and procedure-related complications were evaluated. Success was defined as an IOP ≤21 mm Hg without (complete) or with (qualified) use of glaucoma medication. Results Forty eyes in 40 patients with angle recession glaucoma underwent successful circumferential catheterisation. The mean patient age was 42±13 years. In patients with penetrating canaloplasty that was deemed to be completely successful, the mean IOP decreased from a preoperative value of 37.8±12.3 mm Hg on 3.3±1.2 anti-glaucoma medications to 18.5±6.4 mm Hg on 1.2±1.4 medications, 14.9±4.6 mm Hg on 0.1±0.5 medications, 15.7±5.4 mm Hg on 0.1±0.4 medications and 14.8±3.6 mm Hg on 0.1±0.5 medications at 1, 3, 6 and 12 months postoperatively (p<0.05). Complete success was achieved in 35/40 eyes (87.5%) at 6 months and in 34/38 (89.5%) at 12 months. Hyphema (18/40, 45.0%) and transient IOP elevation (≥30 mm Hg, 9/40, 22.5%) were the most common postoperative complications. Conclusion Penetrating canaloplasty significantly reduces IOP and has a high success rate in angle recession glaucoma. [ABSTRACT FROM AUTHOR]
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- 2023
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28. Progressive Macular Vessel Density Loss Observed on Optical Coherence Tomography Angiography in Glaucoma Patients With Single-Hemifield Visual Field Defects.
- Author
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Sigeng Lin, Shaodan Zhang, Xiao Shang, Juan Gu, Cong Ye, Xiaoyan Wang, Kun Zhou, Yu Xiang George Kong, and Yuanbo Liang
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- 2023
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29. The association between nearwork-induced transient myopia and progression of refractive error: A 3-year cohort report from Beijing Myopia Progression Study
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Zhong Lin, Balamurali Vasudevan, Kenneth J. Ciuffreda, Yuanbo Liang, and Hong Jia Zhou
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medicine.medical_specialty ,Refractive error ,genetic structures ,Emmetropia ,Refractive progression ,Refraction, Ocular ,03 medical and health sciences ,0302 clinical medicine ,Ophthalmology ,medicine ,Myopia ,Humans ,Dioptre ,business.industry ,Confounding ,Accommodation, Ocular ,medicine.disease ,Refractive Errors ,Hyperopia ,Beijing ,Cohort ,030221 ophthalmology & optometry ,Original Article ,business ,Nearwork-induced transient myopia ,030217 neurology & neurosurgery ,Optometry - Abstract
Purpose To investigate the natural change of nearwork-induced transient myopia (NITM), and its association with the progression of refractive error. Methods Students of the Beijing Myopia Progression Study were examined at baseline and follow-up examinations, which included cycloplegic autorefraction. Initial NITM and its decay were assessed objectively immediately after binocularly-viewing and performing a sustained 5-minute near task (20 cm). Results There were 223 students with both NITM and cycloplegic refractive data enrolled. There were 142 myopic (63.7%), 32 emmetropic (14.4%), and 49 hyperopic (22.0%) students according to their baseline cycloplegic refraction. The annual refractive change was −0.45 (−0.73, −0.21) D. From the baseline to the one-year and two-year follow-up periods, the initial NITM (median) increased significantly in the myopic students (0.16, 0.21, and 0.20D, p = 0.01, respectively). The overall proportion of NITM decay types shifted significantly from none being induced at baseline (non-induced: 17.0%, complete decay 57.4%, incomplete decay 25.6%) to incomplete decay at the 2-year follow-up (non-induced: 6.7%, complete decay 65.0%, incomplete decay 28.3%, p = 0.01). For the hyperopic students, after adjusting for risk factors, for every 1 diopter increase in the initial NITM at baseline, there was approximately a −1.48 diopter more relative myopic refractive progression (p = 0.01). No significant association was found between refractive change and the NITM parameters for either the myopic or emmetropic students after adjusting for the same confounders. However, this relation was significant in the hyperopes (p = 0.01). Conclusion NITM was only found to be significantly associated with the progression of a myopic refractive shift among the hyperopes.
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- 2020
30. Design and baseline data of a population-based metabonomics study of eye diseases in eastern China: the Yueqing Ocular Diseases Investigation
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Yanting Sun, Kemi Feng, Yuanbo Liang, Fan Lu, Sigeng Lin, Meixiao Shen, Jia Qu, Liang Wen, Yue Zhou, Kwapong Willaim Robert, Jin Li, Jingwei Zheng, and Yuxuan Deng
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Pediatrics ,medicine.medical_specialty ,Intraocular pressure ,Visual acuity ,Population ,Visual impairment ,03 medical and health sciences ,Ophthalmic epidemiology ,0302 clinical medicine ,lcsh:Ophthalmology ,Baseline ,medicine ,education ,education.field_of_study ,medicine.diagnostic_test ,business.industry ,Research ,Fundus photography ,Anthropometry ,Metabonomics ,lcsh:RE1-994 ,030221 ophthalmology & optometry ,Screening ,030211 gastroenterology & hepatology ,Sample collection ,medicine.symptom ,business ,Body mass index - Abstract
Background China is undergoing a massive transition toward an urban and industrial economy. These changes will restructure the demographics and economy which will eventually influence the future patterns of disease. The risk factors of vision-impairing eye diseases remain ambiguous and poorly understood. Metabolomics is an ideal tool to understand and shed light on the ocular disease mechanisms for earlier treatment. This article aims to describe the design, methodology and baseline data of the Yueqing Ocular Diseases Investigation (YODI), a developed county population-based study to determine the prevalence and primary causes of visual impairment; also with metabonomics analysis we aimed to identify, predict and suggest some preventive biomarkers that cause blindness. Methods A population-based, cross-sectional study. Randomized clustering sampling was used to identify adults aged 50 years and older in Xiangyang Town, Yueqing county-level City. The interviews covered demographic, behavioral, ocular risk factors and mental health state. The ocular examination included visual acuity, autorefraction, intraocular pressure, anterior and posterior segment examinations, fundus photography, retinal tomography and angiography, and visual field testing. Anthropometric measurements included height and weight, waist and hip circumference, blood pressure, pulse rate, electrocardiogram, and abdominal ultrasound scan. A venous blood sample was collected for laboratory tests and metabonomics studies. Results Of the 5319 individuals recruited for the YODI, 4769 (89.7%) subjects were enrolled for analyses. The median age was 62.0 years, and 45.6% were male. The educational level of illiteracy or semi-illiteracy, primary, middle and high school or above was 29.8%, 45.5%, 20.1%, and 3.3%, respectively. Majority of the participants were female, younger, and less educated when compared with nonparticipants. The average body mass index and waist-hip ratios were 24.4 ± 3.4 kg/m2 and 0.9 ± 0.1 respectively. Blood sample collection reached a sample size of 1909 (479 from subjects with self-reported diabetes and 1430 from one-third of the 4290 subjects without self-reported diabetes). Conclusions The YODI provides population-based data with a high response rate (89.7%) on the prevalence and primary causes of major vision-impairing eye diseases in developed county areas in eastern China. Metabonomics analysis from YODI will provide further association of metabolic characteristics with the visual impairment eye diseases. The risk prediction model could be created and has the potential to be generalized to developed eastern areas in China for prevention.
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- 2020
31. Population-based associations between progression of normal-tension glaucoma and Yang-deficient constitution among Chinese persons.
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Lewei Tang, Liang Chen, Cong Ye, Jingwei Zheng, Yi Zhou, Yan Tao, Qiangjie Huang, Xiaoyan Wang, Xiao Shang, Xiafei Pan, Congdon, Nathan, and Yuanbo Liang
- Abstract
Purpose To explore the association between constitution types as defined by traditional Chinese medicine (TCM) and risk for normal-tension glaucoma (NTG). Design Population-based cohort study. Methods Persons were identified in a population cohort aged ≥30 years with NTG, defined as having an untreated mean intraocular pressure measurement ≤21 mm Hg over six separate occasions, with no single reading >24 mm Hg (as in the Collaborative Normal Tension Glaucoma Study). The Body Constitution in Traditional Chinese Medicine Questionnaire was used to assess each participant's TCM constitution types. The association between various constitutions and visual field progression according to Early Manifest Glaucoma Trial criteria was assessed using Cox regression HR models. Results Among 142 participants (245 eyes), 23 persons (17.6%) and 25 eyes (10.2%) progressed, over a mean (SD) follow-up duration of 3.49 (0.99) years. Progression rates were highest in participants with Yang-deficient constitution (n=19, 13.4%), among whom 7 (36.8%) exhibited worsening fields. After adjusting for sex, age, central corneal thickness, retinal nerve fibre layer thickness and mean deviation on visual field testing, Yang-deficient constitution (HR 4.63, 95% CI 1.77 to 12.1, p=0.002) and higher mean intraocular pressure during follow-up (HR 1.25, 95% CI 1.01 to 1.56, p=0.044) were associated with field progression. Conclusions Yang-deficient constitution and higher intraocular pressure are risk factors for visual field progression in NTG patients. Yang deficiency is characterised by abnormal vasoregulation, and these results may be consistent with prior studies linking NTG progression to Raynaud's phenomenon and migraine. [ABSTRACT FROM AUTHOR]
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- 2023
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32. Intraocular asymmetry of visual field defects in primary angle-closure glaucoma, high-tension glaucoma, and normal-tension glaucoma in a Chinese population
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Cong Zhang, Xiang Xu, Nathan Congdon, Jingwei Zheng, Wenqing Ye, Fan Lu, Jingjing Zuo, Cong Ye, Hongte Zhang, Xiaoyan Wang, Junhong Jiang, Xiao Shang, Yuanbo Liang, Jingjing Hu, and Shaodan Zhang
- Subjects
Male ,medicine.medical_specialty ,China ,genetic structures ,Science ,Glaucoma ,Primary angle-closure glaucoma ,Severity of Illness Index ,Article ,03 medical and health sciences ,0302 clinical medicine ,Normal tension glaucoma ,Ophthalmology ,Medicine ,Humans ,Low Tension Glaucoma ,Eye diseases ,Intraocular Pressure ,High tension glaucoma ,Aged ,Chinese population ,Multidisciplinary ,business.industry ,Middle Aged ,medicine.disease ,eye diseases ,Visual field ,Peripheral ,Cross-Sectional Studies ,Population Surveillance ,030221 ophthalmology & optometry ,Optic nerve diseases ,Visual Field Tests ,Female ,sense organs ,Visual Fields ,business ,Glaucoma hemifield test ,Glaucoma, Angle-Closure ,030217 neurology & neurosurgery ,psychological phenomena and processes - Abstract
Direct comparison data on spatial patterns of visual field (VF) defects among primary angle-closure glaucoma (PACG), high-tension glaucoma (HTG) and normal-tension glaucoma (NTG) are not available. We aimed to compare the intraocular asymmetry of VF loss among patients with PACG, NTG and HTG across different severity levels. A total of 162 eyes of 114 patients with PACG, 111 eyes of 74 patients with HTG and 148 eyes of 102 patients with NTG were included. VF defects were categorized into 3 stages (early, moderate, and advanced), and each hemifield was divided into 5 regions according to the Glaucoma hemifield test (GHT). The mean total deviation (TD) of each GHT region was calculated. In the early stage, the paracentral, peripheral arcuate 1 and peripheral arcuate 2 regions in the superior hemifield in the NTG group had significantly worse mean TDs than their corresponding regions in the inferior hemifield. In the advanced stage, the central region in the superior hemifield in the PACG group had a significantly worse mean TD than that in the inferior hemifield. There was no significant difference in the mean TD for any of the five regions between hemifields across all severity levels in the in the HTG group. The superior hemifield was affected more severely than the inferior hemifield in all three subtypes of primary glaucoma. This asymmetric tendency was more pronounced in NTG than in PACG and HTG.
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- 2021
33. Automated segmentation of the optic disc from fundus images using an asymmetric deep learning network
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Yize Chen, Hao Chen, Juan Gu, Yuanbo Liang, Lei Wang, Jiantao Pu, and Weijie Zhang
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Similarity (geometry) ,Computer science ,Glaucoma ,02 engineering and technology ,Fundus (eye) ,01 natural sciences ,Article ,Artificial Intelligence ,0103 physical sciences ,0202 electrical engineering, electronic engineering, information engineering ,medicine ,Segmentation ,010306 general physics ,Block (data storage) ,Intersection (set theory) ,business.industry ,Deep learning ,Pattern recognition ,medicine.disease ,medicine.anatomical_structure ,Signal Processing ,020201 artificial intelligence & image processing ,Computer Vision and Pattern Recognition ,Artificial intelligence ,business ,Software ,Optic disc - Abstract
Accurate segmentation of the optic disc (OD) regions from color fundus images is a critical procedure for computer-aided diagnosis of glaucoma. We present a novel deep learning network to automatically identify the OD regions. On the basis of the classical U-Net framework, we define a unique sub-network and a decoding convolutional block. The sub-network is used to preserve important textures and facilitate their detections, while the decoding block is used to improve the contrast of the regions-of-interest with their background. We integrate these two components into the classical U-Net framework to improve the accuracy and reliability of segmenting the OD regions depicted on color fundus images. We train and evaluate the developed network using three publicly available datasets (i.e., MESSIDOR, ORIGA, and REFUGE). The results on an independent testing set (n=1,970 images) show a segmentation performance with an average Dice similarity coefficient (DSC), intersection over union (IOU), and Matthew's correlation coefficient (MCC) of 0.9377, 0.8854, and 0.9383 when trained on the global field-of-view images, respectively, and 0.9735, 0.9494, and 0.9594 when trained on the local disc region images. When compared with the other three classical networks (i.e., the U-Net, M-Net, and Deeplabv3) on the same testing datasets, the developed network demonstrates a relatively higher performance.
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- 2021
34. Refractive change and incidence of myopia among rural Chinese children: the Handan Offspring Myopia Study.
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Zhong Lin, Vasudevan, Balamurali, Tieying Gao, Hongjia Zhou, Ciuffreda, Kenneth J., and Yuanbo Liang
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Purpose To assess the refractive change and incidence of myopia, as well as their risk factors, among Chinese rural children aged 6-17 years. Methods Children who completed the baseline vision examination of the Handan Offspring Myopia Study were re-examined, including both cycloplegic and non-cyloplegic autorefraction, with a mean follow-up time of 42.4±1.47 months. Results A total of 601 children (68.5%) who completed both baseline and the follow-up examinations were enrolled. The cumulative refractive change and axial length change were -0.53±1.03 diopter and 0.39±0.46 mm (-0.15 diopter/year and 0.11 mm/year), respectively. A hundred and five out of the 469 non-myopic children at baseline become myopic at the follow-up, yielding a cumulative myopia incidence of 22.4% (95% CI: 18.6% to 26.2%), or annual myopia incidence of 6.3%. After adjustment, younger age (ß=0.08, p<0.001), more myopic baseline refraction (ß=0.31, p<0.001), larger difference between cycloplegic and non-cycloplegic refraction (ß=-0.20, p=0.007) and more myopic paternal refraction (ß=0.09, p=0.007) were found to be associated with more rapid myopic refractive change. More myopic baseline refraction (relative risk (RR), 95% CI: 0.19, 0.13-0.28, p<0.001) and more myopic paternal refraction (RR, 95% CI: 0.92, 0.84-1.00, p=0.039) were also associated with myopia incidence. Conclusion Relatively low myopic refractive change and myopia incidence were found in this study cohort. Children's refraction and paternal refraction were associated with both myopic refractive change and myopia incidence. Such information will be helpful for further comparisons in other rural versus urban areas of China, and other countries. [ABSTRACT FROM AUTHOR]
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- 2022
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35. Knowledge, attitudes and practices related to seeking medical eyecare services by adults with moderate-to-severe visual impairment in rural Yueqing, Wenzhou, China :A cross-sectional survey
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Lynne Lohfeld, Jia Qu, Kun Zhou, Yuanbo Liang, Lin Shan Li, Le Le Cui, Wei He Zhou, and Zheng Yan Ge
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knowledge ,medicine.medical_specialty ,Visual acuity ,genetic structures ,Cross-sectional study ,practices ,Visual impairment ,visual impairment ,eye care service ,03 medical and health sciences ,0302 clinical medicine ,lcsh:Ophthalmology ,Practices ,medicine ,Response rate (survey) ,Investigation ,medicine.diagnostic_test ,business.industry ,Knowledge level ,Eye care service ,eye diseases ,Stratified sampling ,Ophthalmology ,Knowledge ,Attitude ,lcsh:RE1-994 ,Eye examination ,attitude ,Family medicine ,030221 ophthalmology & optometry ,medicine.symptom ,Rural area ,business - Abstract
AIM: To evaluate the knowledge, attitudes, and practices regarding eye-care seeking practices of visually impaired adults in a rural area Yueqing, and explore factors influencing their behavior. METHODS: A stratified sampling method was used to select 48 villages in Yueqing, from which 2400 people were selected to receive vision screenings conducted by oculists during a household visit. Those presenting visual acuity≥0.5 logMAR in either eye completed a self-designed questionnaire investigating their knowledge about medical eye-care seeking, attitudes about eye health and eye-care-seeking behavior. RESULTS: Totally 165 people with moderate-to-severe visual impairment were identified (6.9%, 165/2400), and 146 eligible participants were recruited (response rate: 88.4%, mean age: 68.6±15.0y), among which 88 (60.3%) were female. They had 82 (56.2%) and 64 (43.8%) monocular and binocular visual impairments respectively. A total of 67 (45.9%) subjects demonstrated a high knowledge level about medical eye-care seeking and 88 (60.3%) had self-rated poor vision, with 23 (15%) receiving regular vision checks. The 105 (71.9%) subjects had never been to hospital for an eye examination. “No need” and “schedule conflicts” were the main reasons for not seeking eye care. Having extensive knowledge of medical eye-care seeking was positively associated with high education levels (OR=3.73, P=0.045) and negatively correlated with older age (OR=0.97, P=0.043). Both the self-perceived vision condition (OR=2.59, P=0.03) and regular vision check behavior (OR=6.50, P
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- 2020
36. High myopia is protective against diabetic retinopathy via thinning retinal vein: A report from Fushun Diabetic Retinopathy Cohort Study (FS-DIRECT)
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Zhong Lin, Gang Zhai, Feng Hua Wang, Cong Xie, Yu Dou, Yuanbo Liang, Yu Wang, Liang Wen, Dong Li, and Xiao Xia Ding
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Male ,medicine.medical_specialty ,China ,Central retinal vein ,Retinal Vein ,genetic structures ,Endocrinology, Diabetes and Metabolism ,Risk Assessment ,03 medical and health sciences ,0302 clinical medicine ,Risk Factors ,Diabetes mellitus ,Ophthalmology ,High myopia ,Internal Medicine ,medicine ,Myopia ,Humans ,030212 general & internal medicine ,Aged ,Chinese population ,Diabetic Retinopathy ,business.industry ,Diabetic retinopathy ,Middle Aged ,Protective Factors ,medicine.disease ,eye diseases ,medicine.anatomical_structure ,Cross-Sectional Studies ,Diabetes Mellitus, Type 2 ,030221 ophthalmology & optometry ,Original Article ,central retinal vein ,Female ,Cardiology and Cardiovascular Medicine ,business ,Cohort study - Abstract
Purpose: To investigate the association between high myopia and diabetic retinopathy, and its possible mechanism, in a northeastern Chinese population with type 2 diabetic mellitus. Methods: Patients were included from Fushun Diabetic Retinopathy Cohort Study. High myopia was defined as spherical equivalent of autorefraction less than −5D. Results: A total of 1817 patients [688 (37.9%) diabetic retinopathy, 102 (5.6%) high myopia] were included. Compared to eyes without high myopia, the frequency of diabetic retinopathy and non-proliferative diabetic retinopathy was significantly less in eyes with high myopia (23.5% vs 38.7%, p = 0.002; 22.5% vs 35.3%, p = 0.005). Eyes with high myopia were less likely to have diabetic retinopathy (multivariate odds ratio, 95% confidence interval: 0.39, 0.22–0.68) or non-proliferative diabetic retinopathy (odds ratio, 95% confidence interval: 0.40, 0.23–0.70). High myopia was negatively associated with central retinal venular equivalent (multivariate β, 95% confidence interval: −37.1, −42.3 to −31.8, p Conclusions: High myopia was negatively associated with both diabetic retinopathy and non-proliferative diabetic retinopathy in this northeastern Chinese population. This protective effect may have been partially achieved via thinning retinal veins.
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- 2020
37. Cost-effectiveness and cost-utility of population-based glaucoma screening in China a decision-analytic Markov model
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Frank Kee, Yuanbo Liang, Nathan Congdon, Junhong Jiang, Jianjun Tang, and Ciaran O'Neill
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Medicine(all) ,Cost–benefit analysis ,Open angle glaucoma ,Cost effectiveness ,business.industry ,lcsh:Public aspects of medicine ,030231 tropical medicine ,Psychological intervention ,MEDLINE ,Glaucoma ,lcsh:RA1-1270 ,General Medicine ,medicine.disease ,Quality-adjusted life year ,03 medical and health sciences ,0302 clinical medicine ,Cohort ,Medicine ,030212 general & internal medicine ,business ,health care economics and organizations ,Demography - Abstract
Summary Background Glaucoma, particularly primary angle closure glaucoma (PACG), is a leading cause of global blindness. Nearly half of all people with PACG are of Chinese descent. Population-level glaucoma screening has generally not been found to be cost-effective in high-income countries; however, this assessment has rarely been done in low-income or middle-income countries. We aimed to assess the cost-effectiveness and cost-utility of population-level glaucoma screening in China. Methods We developed decision-analytic Markov models for separate and combined screening for PACG and primary open angle glaucoma (POAG) to evaluate costs and benefits of community-level screening versus opportunistic case finding from a societal perspective. A cohort of individuals was followed in the model from age 50 years through a total of 30 1-year Markov cycles. Analyses were done separately for rural and urban settings. We did a meta-analysis of glaucoma prevalence studies in China to obtain prevalence estimates for PACG and POAG. Screening costs were taken from a Chinese screening programme and treatment costs from a tertiary Chinese eye hospital. Main outcomes were incremental cost-utility ratios (ICURs) using quality-adjusted life-years and incremental cost-effectiveness ratios (ICERs) using years of blindness avoided. We did one-way deterministic and simulated probabilistic sensitivity analyses to reflect uncertainty around ICURs and ICERs. Findings Compared with no screening, combined screening of POAG and PACG in rural China is predicted to result in an ICUR of US$569 (95% CI 17 to 4180) and an ICER of $1280 (−58 to 7940), both of which are below the WHO cost-effectiveness threshold of one to three times rural gross domestic product. For the urban China setting, combined screening is predicted to result in fewer net costs and greater gain in health benefits than no screening. Findings were robust in all sensitivity analyses. Over 30 years, a total of 246 (95% CI 63 to 628) and 1325 (510 to 2828) years of blindness are predicted to be avoided for every 100 000 rural and urban residents screened, respectively. Interpretation Population screening for glaucoma (POAG and PACG combined) is likely to be cost-effective in both urban and rural China. Future studies should investigate the effectiveness of interventions to improve acceptance of definitive care among people screened. Funding Ulverscroft Foundation, Wenzhou Medical University Research Fund, Zhejiang Province Health Innovation Talents Project, and Wenzhou's Ten Major Livelihood Issues 2015.
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- 2019
38. Generational Difference of Axial Length and Its Risk Factors in Urban and Rural China
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Yuanbo Liang, Balamurali Vasudevan, Zhong Lin, Kenneth J. Ciuffreda, Tie Ying Gao, and Hong Jia Zhou
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Article Subject ,business.industry ,Multivariable regression analysis ,Offspring ,Axial length ,03 medical and health sciences ,Ophthalmology ,0302 clinical medicine ,lcsh:Ophthalmology ,Beijing ,lcsh:RE1-994 ,030221 ophthalmology & optometry ,Medicine ,030212 general & internal medicine ,Longitudinal cohort ,Rural area ,business ,China ,Research Article ,Demography - Abstract
Purpose. To compare the axial length difference (ALD) and the estimated generational axial length shift (ALS) from parents to their children and its risk factors in urban and rural China. Methods. Participants were enrolled from two longitudinal cohort studies, the Beijing Myopia Progression Study (BMPS) and the Handan Offspring Myopia Study (HOMS). Ocular biometry was performed in both parents and their children. ALD was defined as the difference between the children’s axial length and the corresponding parental axial length. Generational ALS was estimated according to a binominal prediction model at 18 years of age. Results. 237 and 380 urban and rural Chinese children (6–17 years) and their parents from the BMPS and HOMS, respectively, were enrolled. Children’s axial length was estimated to be closest to the parental axial length at 11 and 9 years of age in the urban and rural areas, respectively; the estimated generational ALS would be 1.53 and 0.57 mm, respectively. Multivariable regression analysis revealed that older children (urban β = 0.26, p<0.001; rural β = 0.11, p<0.001) and males had larger ALD (urban β = 0.55, p<0.001; rural β = 0.52, p<0.001) in both areas. Furthermore, urban children with more educated parents (fathers: β = −0.30, p=0.002; mothers: β = −0.29, p=0.004) and more outdoor activity (β = −0.23, p=0.006) had a less ALD. Conclusions. The urban generational axial length shift was estimated to be approximately 1 mm longer than that of the rural area. These results suggest different environmental effects on the ocular development in these two populations of Chinese children.
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- 2019
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39. The value of cycloplegia in optometric refraction of adults in a population study
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Weihe Zhou, Ningli Wang, Brendan Ross, Nathan Congdon, Yuanbo Liang, and Catherine Jan
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Adult ,Male ,China ,Mydriatics ,Refraction, Ocular ,03 medical and health sciences ,0302 clinical medicine ,Prevalence ,Medicine ,Humans ,030212 general & internal medicine ,business.industry ,Vision Tests ,Cycloplegia ,General Medicine ,Middle Aged ,Refractive Errors ,Refraction ,Ophthalmology ,Population Surveillance ,030221 ophthalmology & optometry ,Optometry ,Population study ,Female ,medicine.symptom ,business ,Value (mathematics) - Published
- 2018
40. Effect of community screening on the demographic makeup and clinical severity of glaucoma patients receiving care in urban China
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Juanyuan Yang, Xiang Xu, Ruizhu Sun, Cong Ye, Nathan Congdon, Junhong Jiang, Wen Ou, Yuanbo Liang, Cheng Hu, Xianyao Peng, and Fan Lu
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Male ,China ,Intraocular pressure ,medicine.medical_specialty ,Urban Population ,genetic structures ,Population ,MEDLINE ,Glaucoma ,Community screening ,Severity of Illness Index ,Tonometry, Ocular ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Severity of illness ,Humans ,Medicine ,Community Health Services ,Prospective Studies ,030212 general & internal medicine ,Prospective cohort study ,education ,Intraocular Pressure ,Aged ,education.field_of_study ,business.industry ,Middle Aged ,medicine.disease ,eye diseases ,Ophthalmology ,030221 ophthalmology & optometry ,Visual Field Tests ,Female ,Ocular Hypertension ,sense organs ,Visual Fields ,business ,Cohort study - Abstract
PURPOSE: To assess differences in clinical and demographic characteristics between glaucoma patients identified by community screening and those newly diagnosed in hospital in a Chinese setting.DESIGN: Prospective comparative cohort study.METHODS: 373 patients identified with glaucoma among 27,000 persons undergoing community screening were enrolled as the Screening group. The Clinic group consisted of 119 consecutively-presenting, newly-diagnosed glaucoma patients in hospital.PRIMARY OUTCOME: mean deviation (MD), visual field index (VFI) and pattern standard deviation (PSD) on Humphrey Field Analyzer, and intraocular pressure (IOP). Disease severity was categorized into five stages based on MD.RESULTS: 89.6% (328/373) of Screening Group patients had IOP CONCLUSION: Glaucoma patients detected through community screening had significantly milder damage, and were more likely to include under-served groups (women, elderly) than those newly diagnosed in a clinic in this setting. Comparison with population studies suggests that cases of glaucoma with IOP < 21 mmHg are severely under-ascertained in China, which may be improved by screening.
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- 2018
41. Cone parameters in different vision levels from the adaptive optics imaging.
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Huanhuan Cheng, Ciuffreda, Kenneth J., Huilu Jiang, Kun Zhou, Sigeng Lin, Jingwei Zheng, Xinping Yu, Vasudevan, Balamurali, Yuanbo Liang, Cheng, Huanhuan, Jiang, Huilu, Zhou, Kun, Lin, Sigeng, Zheng, Jingwei, Yu, Xinping, and Liang, Yuanbo
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- 2021
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42. Laser Peripheral Iridotomy versus Trabeculectomy as an Initial Treatment for Primary Angle-Closure Glaucoma
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Yan Yun Chen, Ningli Wang, Ravi Thomas, Hai Lin Meng, Xing Wang, Shi Song Rong, Yuanbo Liang, and Su Jie Fan
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medicine.medical_specialty ,Ophthalmic examination ,Article Subject ,genetic structures ,medicine.medical_treatment ,Glaucoma ,Primary angle-closure glaucoma ,law.invention ,03 medical and health sciences ,0302 clinical medicine ,Randomized controlled trial ,lcsh:Ophthalmology ,law ,Ophthalmology ,medicine ,Initial treatment ,Trabeculectomy ,030212 general & internal medicine ,business.industry ,medicine.disease ,eye diseases ,Surgery ,Laser peripheral iridotomy ,lcsh:RE1-994 ,030221 ophthalmology & optometry ,sense organs ,business ,Peripheral anterior synechiae ,Research Article - Abstract
Purpose. To compare laser peripheral iridotomy (LPI) with trabeculectomy as an initial treatment for primary angle-closure glaucoma (PACG) with peripheral anterior synechiae (PAS) ≥ 6 clock hours. Methods. Patients were drawn from two randomized controlled trials. 38 eyes of 38 patients (PAS ≥ 6 clock hours) were treated with LPI (group 1) while 111 eyes of 111 PACG patients (PAS ≥ 6 clock hours) underwent primary trabeculectomy (group 2). All patients underwent a comprehensive ophthalmic examination at baseline and at postoperative visits and were followed up for a minimum of one year. Results. Group 2 had higher baseline IOP (45.7 ± 14.8 mmHg versus 34.3 ± 14.3 mmHg) than group 1 and more clock hours of PAS (10.4 ± 1.9 versus 9.0 ± 2.2). IOPs at all postoperative visits were significantly lower in group 2 than in group 1 (p=0.000). Five eyes in group 1 required trabeculectomy. 17 of the 38 eyes in group 1 (44.7%) required IOP-lowering medications as compared to seven of the 111 eyes in group 2 (6.3%). Cataract progression was documented in 2 eyes (5.3%) in group 1 and 16 eyes (14.4%) in group 2. Conclusions. Primary trabeculectomy for PACG (PAS ≥ 6 clock hours) is more effective than LPI in lowering IOP.
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- 2017
43. Validity and feasibility of a self-administered home vision examination in Yueqing, China: a cross-sectional study.
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Zhengyan Ge, Linshan Li, Lynne Lohfeld, Chunjie Lu, Nathan Congdon, Sigeng Lin, Yuxuan Deng, Yuan Lan, Shaodan Zhang, Laurence Hou, Weihe Zhou, Lele Cui, Jia Qu, and Yuanbo Liang
- Abstract
Objective To investigate the validity and feasibility of a self-administered home vision examination programme in China. Design Cross-sectional study. Setting Yueqing, China. Participants A two-stage convenience sampling procedure was used to randomly select 600 households from 30 communities participating in the Yueqing Eye Study (YES). The aim of YES is to encourage home-based vision screening, reporting of visual acuity (VA) annually through social media and encouraging people to attend follow-up clinic appointments as a way to improve eye care access for adults with VA ≤+0.5 log of the minimum angle of resolution (logMAR). Interventions Household screeners (one per household) who tested other family members’ VA completed a questionnaire on family structure, demographic information and knowledge about screening procedures. Other family members then underwent confirmatory VA testing by researchers. Outcome measures The completion rate of home-based VA screening, its sensitivity and specificity were used to evaluate validity. Factors that determined whether families participated in the self-VA screening were used to evaluate feasibility. Results 345 (66%) of the 523 (87.2%) households with valid data form their home-based vision examinations also were retested by researchers. There was no statistically significant difference in scores on the family-administerd or researcher-administerd VA test (VA≤+0.5 logMAR, p=0.607; VA >+0.5 logMAR, p=0.612). The sensitivity and specificity of home-based vision screening were 80.5% (95% CI 70.2% to 86.9%) and 95.1% (95% CI 92.6% to 96.8%), respectively. 14.7% (77/523) of tested respondents had VA ≤+0.5 logMAR. Predictors of performing home screening for VA remaining in regression models included higher economic status (‘fair and above’ vs ‘poor’: OR 1.74; 95% CI 1.08 to 2.76; p=0.022), age (<45 years vs ≥45 years: OR 0.46; 95% CI 0.25 to 0.85; p=0.014) and living in a nuclear (OR 5.17; 95% CI 2.86 to 9.36; p<0.001) or extended family (OR 8.37; 95% CI 4.93 to 14.20; p<0.001). Conclusion Self-administered home vision screening is reliable and highly accepted by Chinese adults. [ABSTRACT FROM AUTHOR]
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- 2020
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44. One-year outcome of low dose laser cyclophotocoagulation for capsular tension ring-induced malignant glaucoma A case report.
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Haishuang Lin, Guangming Zhou, Shaodan Zhang, Fang Huang, and Yuanbo Liang
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- 2020
45. A survey of perceived training differences between ophthalmology residents in Hong Kong and China
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Xiaofei Man, Alvin L. Young, Simon Kwoon-Ho Chow, Xiu Juan Zhang, Vishal Jhanji, Fenghua Wang, Hunter G L Yuen, Ming-ming Yang, Dennis S.C. Lam, Yuanbo Liang, Nathan Congdon, and Zhong Lin
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Adult ,Male ,Program evaluation ,China ,medicine.medical_specialty ,Biomedical Research ,Eye Diseases ,Cataract ,Education ,Interquartile range ,Surveys and Questionnaires ,Ophthalmology ,medicine ,Training ,Humans ,Medicine(all) ,business.industry ,Resident training ,Internship and Residency ,General Medicine ,Residency ,Family medicine ,Hong Kong ,Female ,Job satisfaction ,business ,Research Article ,Program Evaluation - Abstract
Background: To study the differences in ophthalmology resident training between China and the Hong Kong Special Administrative Region (HKSAR).Methods: Training programs were selected from among the largest and best-known teaching hospitals. Ophthalmology residents were sent an anonymous 48-item questionnaire by mail. Work satisfaction, time allocation between training activities and volume of surgery performed were determined.Results: 50/75 residents (66.7 %) from China and 20/26 (76.9 %) from HKSAR completed the survey. Age (28.9 ± 2.5 vs. 30.2 ± 2.9 years, p = 0.15) and number of years in training (3.4 ± 1.6 vs. 2.8 ± 1.5, p = 0.19) were comparable between groups. The number of cataract procedures performed by HKSAR trainees (extra-capsular, median 80.0, quartile range: 30.0, 100.0; phacoemulsification, median: 20.0, quartile range: 0.0, 100.0) exceeded that for Chinese residents (extra-capsular: median = 0, p 50 % of time on charts: 62.5 % versus 5.3 %, p
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- 2015
46. Comparisons of Different Metabolic Syndrome Definitions and Associations with Coronary Heart Disease, Stroke, and Peripheral Arterial Disease in a Rural Chinese Population
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Jingang Yang, Qiushan Tao, Yujie Shi, Xinrong Duan, Fenghua Wang, Xinxin Lu, Yuanbo Liang, Xilin Lu, Ningli Wang, Yaping Tian, and Jiangping Wen
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Adult ,Male ,Rural Population ,medicine.medical_specialty ,China ,Cross-sectional study ,lcsh:Medicine ,Coronary Artery Disease ,Coronary artery disease ,Peripheral Arterial Disease ,Risk Factors ,Internal medicine ,Diabetes mellitus ,Prevalence ,Medicine ,Humans ,cardiovascular diseases ,lcsh:Science ,Stroke ,Metabolic Syndrome ,Multidisciplinary ,business.industry ,lcsh:R ,Middle Aged ,medicine.disease ,Chinese people ,Blood pressure ,Cross-Sectional Studies ,Population Surveillance ,Cardiology ,lcsh:Q ,Female ,Metabolic syndrome ,business ,Body mass index ,Research Article - Abstract
Objectives We estimated the prevalence of metabolic syndrome (MetS) and compared associations of different MetS definitions with coronary heart disease (CHD), stroke, and peripheral arterial disease (PAD) in a rural Chinese population. Methods Among 4,748 residents (2,145 men and 2,603 women) aged 30+ years in rural China from 2006 to 2007, the prevalence of MetS was estimated by using five different definitions: modified World Health Organization (WHO), Chinese Diabetes Society (CDS), the updated National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATP III) for Asian-Americans, International Diabetes Federation (IDF), and Joint Interim Statement (JIS). Multivariable logistic regression analyses were implemented to estimate the association between MetS and the prevalence of CHD, stroke and PAD, respectively. Results Prevalence of MetS in men was 11.5% (WHO), 14.8% (CDS), 32.4% (NCEP-ATP III), 27.5% (IDF) and 39.7% (JIS) and in women was 15.7% (WHO), 20.7% (CDS), 54.2% (NCEP-ATP III), 51.5% (IDF) and 54.2% (JIS), respectively. Respective ORs (95% CI) for associating MetS with CHD in men were 1.79 (1.02-3.17), 1.25 (0.69-2.26), 1.61 (1.01-2.58), 1.84 (1.14-2.96), and 1.53 (0.96-2.43). Corresponding ORs (95% CI) for stroke in men were 2.18 (95% CI 1.20 to 3.97), 2.20 (95% CI 1.25 to 3.89), 1.71 (95% CI 1.02 to 2.84), 1.30 (95% CI 0.77 to 2.23), and 1.61 (95% CI 0.97 to 2.68), respectively. In women, CHD and stroke were significantly associated with MetS using all five definitions of MetS. In addition, PAD was associated with all five MetS definitions in men, but not in women. Only hyperglycemia and BMI were significantly associated with PAD in women. Conclusions In this rural Chinese population, the JIS, IDF and CDS criteria may not be more suitable than WHO and updated NCEP-ATPIII definitions for screening high-risk individuals and estimating the risk of CHD and stroke from MetS, especially in men.
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- 2015
47. Generational difference of refractive error and risk factors in the Handan offspring myopia study
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Tie Ying Gao, Kenneth J. Ciuffreda, Yuanbo Liang, Peng Zhang, Zhong Lin, Vishal Jhanji, Ningli Wang, Guang Yun Mao, Balamurali Vasudevan, and Lei Li
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Adult ,Male ,Rural Population ,Refractive error ,China ,Adolescent ,Urban Population ,Offspring ,Cellular and Molecular Neuroscience ,Risk Factors ,Surveys and Questionnaires ,Linear regression ,Myopia ,Medicine ,Humans ,Child ,Life Style ,Dioptre ,Medicine(all) ,business.industry ,Environmental exposure ,Cyclopentolate ,medicine.disease ,Refractive Errors ,Refraction ,Sensory Systems ,Ophthalmology ,Quartile ,Risk factors ,Optometry ,Female ,business ,medicine.drug ,Demography - Abstract
Purpose.: To report the refractive error difference (RED) between parents and their children, and its risk factors, in a rural area of China. Methods.: Children (6–17 years) and their parents (36.2 ± 4.1 years) from the Handan Offspring Myopia Study (HOMS) were enrolled. Cycloplegic autorefraction (cyclopentolate 1%, Topcon KR8800) of the children and noncycloplegic autorefraction of their parents were assessed. A detailed vision-based questionnaire was also completed. Refractive error difference was defined as the difference between the parental spherical equivalent (SE) and their children's SE. Generational myopic shift was defined as the estimated RED when a child would be 18 years old according to a prediction model. Results.: Three hundred fifty-six pairs of parents and 585 children were enrolled. The RED (median, quartiles) increased from −1.33 (−1.99, −0.98) diopters (D) in children aged 6 to 7 years to 0.81 (−0.16, 2.28) D in children aged 16 to 17 years. The children's SE was predicted to approach the parental SE at 14 years of age. Moreover, the children's estimated myopic shift would be 1.03 D. Multiple linear regression revealed that older children (β = 0.23 D/y, P < 0.0001) and girls (β = 0.24, P = 0.01) tended to have a higher RED. Conclusions.: In this rural Chinese population, the children's refraction was estimated to be similar to the parental refraction at 14 years of age. Moreover, the generational myopic shift was estimated to be approximately 1 D at 18 years of age. These data suggest that the generational difference reflects the increasing prevalence of myopia in the younger generation, which is likely due to changes in environmental exposure.
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- 2014
48. Association analysis of cigarette smoking with onset of primary open-angle glaucoma and glaucoma-related biometric parameters
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Yuqian Zheng, Yuqiang Huang, Mingzhi Zhang, Jianwei Lin, Degui Wang, Jian-Huan Chen, Yuanbo Liang, Chukai Huang, Pengfei Wu, and Yi Peng
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Male ,China ,Intraocular pressure ,medicine.medical_specialty ,Open angle glaucoma ,genetic structures ,Glaucoma ,Logistic regression ,Central corneal thickness ,Cohort Studies ,lcsh:Ophthalmology ,Risk Factors ,Cigarette smoking ,Ophthalmology ,Humans ,Medicine ,Risk factor ,Vertical cup-to-disc ratio ,Aged ,Aged, 80 and over ,business.industry ,Smoking ,Case-control study ,General Medicine ,Middle Aged ,medicine.disease ,Primary open angle glaucoma ,eye diseases ,Logistic Models ,lcsh:RE1-994 ,Case-Control Studies ,Cohort ,Female ,sense organs ,business ,Glaucoma, Open-Angle ,Research Article ,Cohort study - Abstract
Background To date, studies on the role played by cigarette smoking in primary open-angle glaucoma (POAG) remains controversial. The current study evaluated cigarette smoking as a risk factor of POAG and its relationships with vertical cup-to-disc ratio (VCDR), central corneal thickness (CCT) and intraocular pressure (IOP) in a Chinese cohort. Methods In a total of 248 unrelated individuals including 30 juvenile-onset POAG (JOAG), 92 adult-onset POAG (AOAG) and 126 sex-matched senile cataract controls, underwent comprehensive ophthalmic examination. Their smoking was obtained and documented by questionnaire. Association of cigarette smoking with POAG was performed using logistic regression controlled for age and sex. Effects of cigarette smoking on VCDR, IOP and CCT were analyzed with multiple linear regression. Results In either JOAG or AOAG, no association of cigarette smoking was found with disease onset (P = 0.692 and 0.925 respectively). In controls and JOAG, no significant effects of smoking were found on VCDR, IOP or CCT (all P > 0.05). Smoking was found to be correlated with decreased CCT in AOAG and combined POAG (JOAG + AOAG) (P = 0.009 and 0.003), but no association with VCDR or IOP was observed (P > 0.05). Conclusions Although cigarette smoking was not found to be risk factor for onset of POAG, it was correlated with CCT in AOAG, and thus might still play a role in the disease course, especially for AOAG.
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- 2012
49. Laser peripheral iridotomy versus laser peripheral iridotomy plus laser peripheral iridoplasty in the treatment of multi-mechanism angle closure: study protocol for a randomized controlled trial.
- Author
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Shida Chen, Jianhua Lv, Sujie Fan, Hong Zhang, Lin Xie, Ling Xu, Bing Jiang, Huipin Yuan, Yuanbo Liang, Shuning Li, Pingyan Chen, Xiulan Zhang, Ningli Wang, Chen, Shida, Lv, Jianhua, Fan, Sujie, Zhang, Hong, Xie, Lin, Xu, Ling, and Jiang, Bing
- Subjects
GLAUCOMA diagnosis ,PREVENTION of disease progression ,GLAUCOMA ,RANDOMIZED controlled trials ,SLIT lamp microscopy ,PUBLIC health ,PATIENTS ,LASER therapy ,IRIS surgery ,ANGLE-closure glaucoma ,CHI-squared test ,COMPARATIVE studies ,CONVALESCENCE ,EXPERIMENTAL design ,IRIS (Eye) ,OPHTHALMIC surgery ,LASERS ,MEDICAL lasers ,RESEARCH methodology ,MEDICAL cooperation ,RESEARCH protocols ,RESEARCH ,TIME ,VISION ,VISUAL acuity ,LOGISTIC regression analysis ,EVALUATION research ,TREATMENT effectiveness ,DISEASE progression ,DIAGNOSIS ,EQUIPMENT & supplies - Abstract
Background: China has the largest burden of primary angle-closure glaucoma (PACG) worldwide. The mechanism of the angle closure is complex and includes pupillary block and non-pupillary block. Currently, opinion is that laser peripheral iridotomy (LPI) alone is not sufficient to prevent disease progression. Laser peripheral iridoplasty (LPIP) is an alternative and effective way of widening the angle recess in eyes that are affected by primary angle closure (PAC). However, it is not known if greater benefit would be achieved using LPI plus LPIP for PAC with multiple mechanisms (MAC). Thus, the aim of this study is to demonstrate if LPI plus LPIP would be more effective than single LPI in controlling the progression of PAC with multiple mechanisms, based on ultrasound biomicroscopy (UBM) classification. A secondary aim is to determine whether or not this would result in the use of less medication and/or prolong the time to antiglaucoma surgery.Methods: This multiple-mechanism angle-closure study will comprise a 3-year, multicenter, randomized, parallel-group, open-label, superiority trial, the aim of which will be to evaluate the safety and efficacy of LPI plus LPIP versus LPI for PAC. It is anticipated that 240 adults, diagnosed with PAC (the mechanism of angle closure will be assessed by UBM and it will be determined whether or not it involves multiple mechanisms) will be recruited from ten ophthalmic centers in China. Participants will be randomly allocated to receive either single LPI or LPI plus LPIP. Participant assessment will be designed to test the rate of disease progression and who will be followed up for 3 years. The primary outcome will be the disease progression rate and a comparison will be made between the LPI and LPI plus LPIP groups using Pearson's χ2 test. Logistic regression analysis will be performed to account for the central effect.Discussion: If the LPI plus LPIP is found to significantly decrease the rate of PAC progression, this intervention could potentially be a standard therapy to be used to treat PAC when multiple mechanisms are involved in angle closure. Subsequently, this would have the potential to delay the rate of PAC progression to PACG and delay the time to the administration of antiglaucoma medication or trabeculectomy surgery.Trial Registration: ClinicalTrials.gov, NCT02613013 . Registered on 24 November 2015. In fact, the study was due to start in late October 2015, however, there were no patients recruited in October, and when we registered at ClinicalTrials.gov on 5 November 2015, we received suggestions on the English translation of our protocol from the PRS Team at Clinicaltrial.gov, so the final successful registration date was on 24 November 2015. [ABSTRACT FROM AUTHOR]- Published
- 2017
- Full Text
- View/download PDF
50. Mixed FEM-Crushable DEM Nested Scheme in Second-Order Computational Homogenization for Granular Materials.
- Author
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Xikui Li, Zenghui Wang, Yuanbo Liang, and Qinglin Duan
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GRANULAR materials ,DISCRETE element method ,FINITE element method ,ASYMPTOTIC homogenization ,ENERGY dissipation ,STRAINS & stresses (Mechanics) - Abstract
A mixed FEM-crushable discrete-element method (DEM) nested scheme in the frame of second-order computational homogenization for granular materials was proposed. The particle breakage followed by the discontinuity and dissipative relative movements between each of two immediate neighboring particles were modeled at the mesoscale to perform both the downscaling and upscaling between the mixed FEM at the macroscopic continuum scale and the crushable DEM at the mesoscopic discrete particle assembly scale. To develop the crushable DEM for modeling the mesostructural evolution within representative volume elements (RVEs) assigned to integrating points of the macroscopic Cosserat continuum in the homogenization, two grain breakage models consisting of crushing criteria and the fracture mode for an individual crushable particle were developed. Not only the contact forces, but also contact moments exerted on each individual grain via the contacting points on the grain surface, were taken into account to set up the proposed crushing criteria. The stress measures, responsible for the particle breakage, involved both the average Cauchy stress tensor and the average couple stress tensor exerted on a crushable particle modeled as the Cosserat continuum. A fracture mode to specify how a crushable parent particle is replaced with a specific arrangement of postcrushing fragments was proposed and implemented. The mass conservation in the postcrushing replacement of fragments was ensured, whereas neither overlaps among the fragments nor overlaps with the fragments of the immediate neighboring particles of the crushable parent particle were introduced. The numerical results demonstrate the performance of the proposed mixed FEM-crushable DEM nested scheme in the frame of second-order computational homogenization for granular materials and the effects of the particle breakage on the failure behavior of the overall geostructure. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
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