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《Survey of ophthalmology》2023,68(5):920-928
There remains limited agreement regarding the efficacy and safety of different antivascular endothelial growth factor (anti-VEGF) agents for the management of polypoidal choroidal vasculopathy (PCV). Our meta-analysis compares different anti-VEGF agents for PCV treatment. Ovid MEDLINE, EMBASE, and Cochrane Library were systematically searched from January 2000 to July 2022. We included articles comparing the efficacy and safety of different anti-VEGF agents, specifically bevacizumab (BEV), ranibizumab (RAN), aflibercept AFL), and brolucizumab (BRO), for patients with PCV. 10,440 studies were identified, 122 underwent full-text review, and seven were included. One study was a randomized trial, and six were observational studies. Ranibizumab and aflibercept were associated with a similar best-corrected visual acuity (BCVA) at the last visit in three observational studies (P = 0.10), similar retinal thickness at the last visit in two observational studies (P = 0.85). One observational study comparing BEV versus RAN found comparable outcomes for final BCVA, retinal thickness, and polyp regression. One randomized trial on BRO versus AFL found comparable outcomes for improvement in BCVA, while anatomical outcomes favored BRO. The available evidence suggests that final BCVA is comparable across different anti-VEGF agents, however, further investigation is warranted due to paucity of evidence.  相似文献   
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阿尔茨海默病是一种进行性且不可逆转的神经系统疾病,由于视网膜和中枢神经系统有相似的胚胎起源和生理特征,眼科检查可提供简单无创的诊断方法。光学相干断层扫描技术(OCT)能够精确地测量视网膜各个组织层面的厚度,以评估视网膜的退行性改变,光学相干断层扫描血管成像(OCTA)可以提供高分辨率三维成像,从而更直观地检测视网膜血管的变化,间接地反映脑神经元和血管的病理特征。就OCT测量视网膜厚度及OCTA测量视网膜血流变化在阿尔茨海默病诊断中的研究进展进行综述。  相似文献   
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AIM: To observe the clinical effect of pars plana vitrectomy (PPV) and silicone oil filling surgery combined with intraoperative posterior scleral staphyloma (PS) marginal retinal photocoagulation in the treatment of high myopic macular hole retinal detachment (MHRD) with PS. METHODS: This was a retrospective clinical study. From May 2017 to March 2020, 62 MHRD patients with PS (62 eyes) were enrolled in the study. Patients were divided into 23G PPV combined with PS marginal retina intraoperative photocoagulation group (combined group) and conventional surgery group (conventional group), with 31 eyes in each. Triamcinolone acetonide and indocyanine green were used to remove the epiretinal membrane and the posterior macular inner limiting membrane (ILM). In the combined group, 2 to 3 rows of retinal photocoagulation were performed on the edge of the PS. The patients were followed up for an average of 8.34±3.21mo. The first retinal reattachment rate, macular hole closure rate, Duration of silicone oil tamponade, best corrected visual acuity (BCVA) and average number of operations were observed and compared between the two groups. RESULTS: The first retinal reattachment rates of the eyes in the combined group and the conventional group were 96.7% (29/31) and 67.7% (21/31), respectively (χ2=6.613, P=0.010). The macular hole closure rates in the combined group and the conventional group were 74.2% (23/31) and 67.7% (21/31), respectively (χ2=0.128, P=0.721). The Duration of silicone oil tamponade of the patients in the combined group was lower than that of the routine group (t=-41.962, P≤0.001). Postoperative logMAR BCVA values of patients in the combined group and the conventional group were 1.27±0.12 and 1.26±0.11, compared with the logMAR BCVA before surgery, each group was improved (t=19.947, t=-19.517, P≤0.001, P≤0.001). There was no significant difference in the logMAR BCVA between the eyes of the two groups (t=-0.394, P=0.695). The average numbers of operations on the eyes in the conventional group and the combined group were 2.39±0.62 and 2.06±0.25 times, the combined group had fewer operations on average (t=-2.705, P=0.009). CONCLUSION: Intraoperative PPV treatment of MHRD with PS combined with PS marginal endolaser photocoagulation can effectively increase the rate of retinal reattachment after the first operation, reduce the number of repeated operations, and reduce the postoperative duration of silicone oil tamponade.  相似文献   
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《Radiography》2022,28(3):663-667
IntroductionAnti-scatter grids efficiently reduce scatter radiation from reaching the imaging receptor, enhancing image quality; however, the patient radiation dose increases in the process. There is disagreement regarding the thickness thresholds for which anti-scatter grids are beneficial. This study aims to establish a thickness threshold for the use of anti-scatter grids to optimise adult knee radiography.MethodsThe study consisted of two phases. In Phase 1 phantom knee radiographs were acquired at varying thicknesses (10–16 cm) and tube voltages (60–80 kV). For each thickness and tube voltage, images with and without an anti-scatter grid were obtained. In Phase 2, two radiologists and three radiographers, evaluated the image quality of these images. Visual Grading Analysis (VGA) scores were analysed using Visual Grading Characteristics (VGC) based on the visualisation of five anatomic criteria.ResultsThe average DAP decreased by 72.1% and mAs by 73.1% when removing the anti-scatter grid. The VGC revealed that overall images taken with an anti-scatter grid have better image quality (AUC ≥0.5 for all comparisons). However, the anti-scatter grids could be removed for thicknesses 10, 12 and 14 cm in conjunction with using 80 kVp,.ConclusionAnti-scatter grids can be removed when imaging adult knees between 10 and 12 cm using any kVp setting since the radiation dose is reduced without significantly affecting image quality. For thicknesses >12 cm, the use of anti-scatter grids significantly improves image quality; however, the radiation dose to the patient is increased. The exception is at 14 cm used with 80 kVp, where changes in image quality were insignificant.Implications for practiceOptimisation by removing anti-scatter grids in adult knee radiography seems beneficial below 12 cm thickness with any kVp value. Since the average knee thickness ranges between 10 and 13 cm, anti-scatter grid can be removed for most patients. Nevertheless, further studies are recommended to test if this phantom-based threshold applies to human subjects.  相似文献   
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