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1.
目的:应用扫频光学相干断层扫描血管成像(SS-OCTA)对比研究白内障术中不同眼内压患者手术前后黄斑区血流的变化情况,为白内障个性化手术参数设计提供临床参考。

方法:前瞻性随机对照研究。收集2021-01/04于四川省人民医院住院行白内障手术的患者61例77眼,使用随机数字表分为A组(37眼)和B组(40眼),术中分别予以75、90cm灌注瓶瓶高,相当于55.5、66.6mmHg术中平均眼内压。所有患者除常规眼科检查外,术前、术后1、7、30d均行黄斑区SS-OCTA检查,观察黄斑区视网膜厚度及放射状毛细血管网(RPCP)层、浅层血管网(SVP)层、中层血管网(IVP)层、深层血管网(DVP)层灌注面积和血管密度。

结果:手术前后各时间点两组患者最佳矫正视力(BCVA)、眼压、黄斑中心凹无血管区(FAZ)面积、黄斑区视网膜厚度及各层灌注面积和血管密度均无组间差异性(均P>0.05),但均有时间差异性(均P<0.05),两组患者术后各时间点BCVA均较术前明显改善,眼压和FAZ面积均较术前下降(均P<0.05),黄斑区视网膜厚度及各层灌注面积和血流密度均较术前增加。

结论:白内障术后黄斑区视网膜厚度及各层血流密度和灌注面积均增加,FAZ面积下降,有助于促进术后视力的恢复,且术中选择55.5、66.6mmHg不同眼内压情况下,患者术后眼底血流改变情况无明显差异,故术中可以灵活选择眼内压,为患者提供个性化手术设计方案。  相似文献   

2.
Diabetic macular ischaemia (DMI) is traditionally defined and graded based on the angiographic evidence of an enlarged and irregular foveal avascular zone. However, these anatomical changes are not surrogate markers for visual impairment. We postulate that there are vascular phenotypes of DMI based on the relative perfusion deficits of various retinal capillary plexuses and choriocapillaris. This review highlights several mechanistic pathways, including the role of hypoxia and the complex relation between neurons, glia, and microvasculature. The current animal models are reviewed, with shortcomings noted. Therefore, utilising the advancing technology of optical coherence tomography angiography (OCTA) to identify the reversible DMI phenotypes may be the key to successful therapeutic interventions for DMI. However, there is a need to standardise the nomenclature of OCTA perfusion status. Visual acuity is not an ideal endpoint for DMI clinical trials. New trial endpoints that represent disease progression need to be developed before irreversible vision loss in patients with DMI. Natural history studies are required to determine the course of each vascular and neuronal parameter to define the DMI phenotypes. These DMI phenotypes may also partly explain the development and recurrence of diabetic macular oedema. It is also currently unclear where and how DMI fits into the diabetic retinopathy severity scales, further highlighting the need to better define the progression of diabetic retinopathy and DMI based on both multimodal imaging and visual function. Finally, we discuss a complete set of proposed therapeutic pathways for DMI, including cell-based therapies that may provide restorative potential.  相似文献   
3.
《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   
4.
邵毅  李乐妍  魏红 《眼科新进展》2022,(11):841-846
糖尿病黄斑水肿(DME)的发病率正逐渐上升,其作为导致糖尿病患者视力不可逆丧失的主要原因,一直受到医学研究者的关注。目前,在应用诸如光学相干断层扫描和抗血管内皮生长因子等针对DME的诊疗方法的同时,多种新兴的解决方案正在被研发。因此,本文将对现有DME的诊断和治疗方案进行总结讨论,以期为未来DME诊疗标准的统一奠定基础。  相似文献   
5.
6.
ObjectiveTo analyze the prevalence of dry and wet age-related macular degeneration (AMD) in patients with diabetes, hypertension and hyperlipidemia, and to analyze the risk factors for AMD.MethodsA population-based cross-sectional epidemiologic study was conducted involving 14,440 individuals. We assessed the prevalence of dry and wet AMD in diabetic and non-diabetic subjects and analyzed the risk factors for AMD.ResultsThe prevalence of wet AMD in diabetic and non-diabetic patients was 0.3% and 0.5%, respectively, and the prevalence of dry AMD was 17% and 16.4%, respectively. The prevalence of wet AMD in healthy, hypertensive, hyperlipidemic, and hypertensive/hyperlipidemic populations was 0.5%, 0.3%, 0.2%, and 0.7%, respectively. The prevalence of dry AMD in healthy, hypertensive, hyperlipidemic, and hypertensive/hyperlipidemic populations was 16.6%, 16.2%, 15.2%, and 17.2%, respectively. Age, sex, body mass index, and use of hypoglycemic drugs or lowering blood pressure drugs were corrected in the risk factor analysis of AMD. Diabetes, diabetes/hypertension, diabetes/hyperlipidemia, and diabetes/hypertension/hyperlipidemia were analyzed. None of the factors analyzed in the current study increased the risk for the onset of AMD.ConclusionThere was no significant difference in the prevalence of wet and dry AMD among diabetic and non-diabetic subjects. Similarly, there was no significant difference in the prevalence of wet and dry AMD among subjects with hypertension and hyperlipidemia. Diabetes co-existing with hypertension and hyperlipidemia were not shown to be risk factors for the onset of dry AMD.  相似文献   
7.
赵文  赵斐  李敏  叶慧芳 《眼科新进展》2022,(12):962-966
目的 探讨补体因子H(CFH)基因多态性与玻璃体液血管内皮生长因子(VEGF)对年龄相关性黄斑变性(AMD)患者抗VEGF疗效影响的交互作用。方法 选取2020年5月~2022年1月广州医科大学附属第三医院眼科149例(149眼)AMD患者为研究对象,根据抗VEGF治疗是否有应答,分为应答组(111例)、无应答组(38例)。比较两组患者CFH基因多态性、玻璃体液VEGF表达水平,比较CFH位点rs1061170不同基因型患者玻璃体液VEGF表达水平,采用Logistic分析抗VEGF疗效的相关影响因素,采用交互作用系数γ分析CFH基因多态性、玻璃体液VEGF的交互作用是否存在及其作用类型。结果 无应答组患者CFH位点rs1061170基因型分布与应答组比较,差异有统计学意义(P<0.05)。无应答组患者玻璃体液VEGF高于应答组(P<0.05)。在全部AMD患者中,玻璃体液VEGF高水平患者CFH位点rs1061170基因型分布与低水平患者比较,差异有统计学意义(P<0.05)。在全部AMD患者中,玻璃体液VEGF、CFH位点rs1061170 CC基因型均是抗VEGF疗效的独立相关影响因素(均为P<0.05)。在全部AMD患者中,单独玻璃体液VEGF的OR值为41.250,单独rs1061170基因型CC的OR值为22.000,两者共存时的OR值为759.000,且γ为1.068,提示患者玻璃体液VEGF升高与CFH位点rs1061170 CC基因型在抗VEGF疗效中呈正向交互作用;同时交互作用<两单独因素OR值的乘积,则患者玻璃体液VEGF升高与CFH位点rs1061170 CC基因型交互作用符合次相乘模型。结论 玻璃体液VEGF升高与CFH位点rs1061170 CC基因型在AMD抗VEGF疗效中呈正向交互作用,且交互作用符合次相乘模型,为临床抗VEGF药物精准使用提供参考。  相似文献   
8.
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   
9.
10.
Reticular pseudodrusen (RPD), or subretinal drusenoid deposits (SDD), refer to distinct lesions that occur in the subretinal space. Over the past three decades, their presence in association with age-related macular degeneration (AMD) has become increasingly recognized, especially as RPD have become more easily distinguished with newer clinical imaging modalities. There is also an increasing appreciation that RPD appear to be a critical AMD phenotype, where understanding their pathogenesis will provide further insights into the processes driving vision loss in AMD. However, key barriers to understanding the current evidence related to the independent impact of RPD include the heterogeneity in defining their presence, and failure to account for the confounding impact of the concurrent presence and severity of AMD pathology. This review thus critically discusses the current evidence on the prevalence and clinical significance of RPD and proposes a clinical imaging definition of RPD that will help move the field forward in gathering further key knowledge about this critical phenotype. It also proposes a putative mechanism for RPD formation and how they may drive progression to vision loss in AMD, through examining current evidence and presenting novel findings from preclinical and clinical studies.  相似文献   
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