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61.
《中国现代医生》2020,58(12):184-192
光学相干断层扫描血管造影通过连续探测同一位置的血管内红细胞运动,生成三维血流信息,获取高分辨率的眼底血管图像。分频幅去相关血流成像演算技术,减少了因眼球轴向运动和组织运动产生的噪点及伪影,优化了信噪比,使得对毛细血管网的检测更具有连贯性。光学相干断层扫描血管造影目前已应用于糖尿病性视网膜病变、年龄相关性黄斑变性、视网膜血管阻塞、青光眼、中心性浆液性脉络膜病变等疾病的诊疗中,具有广阔的临床应用及科研前景。本文就光学相干断层扫描血管造影在眼底微血管定量分析中的应用作综合性论述。  相似文献   
62.
AIM: To compare the safety and efficacy of conbercept intravitreal injection and half-dose photodynamic therapy (PDT) in treating chronic central serous chorioretinopathy (CSC). METHODS: This study was retrospective. Thirty-seven patients (37 eyes) with chronic CSC received conbercept injections while 57 patients (57 eyes) were treated with half-dose PDT. All subjects were followed in 6mo. Outcome measures included change in best-corrected visual acuity (BCVA), central macular thickness (CMT), subfoveal choroidal thickness (SFCT), and resolution of subretinal fluid (SRF). RESULTS: There was no adverse event observed in either treatment group. At the 6-month follow-up, 26 eyes (70.3%) in the conbercept group and 54 eyes (94.7%) in the half-dose PDT group (P<0.05) reached full resolution of SRF. The mean logarithm of the minimum angle of resolution (logMAR) BCVA significantly improved (P<0.001) in both treatment groups with better outcome at early phase in the half-dose PDT group (2wk, 1, and 2mo, P<0.05). All subjects experienced significant CMT improvement (P<0.001) with no statistical difference between the two groups (P>0.05). The SFCT also improved in all subjects (P<0.001) with better outcome in the half-dose PDT group (P<0.05). CONCLUSION: Both intravitreal conbercept and half-dose PDT are safe to use in treating chronic CSC. By 6mo, both treatment groups are efficacious in improving BCVA, reducing CMT and SFCT, and resolving SRF in eyes with chronic CSC. Half-dose PDT may show better outcome at initial phase of treatment in chronic CSC. Longer follow-up period is necessary to study for long-term effect and safety.  相似文献   
63.
AIMS: To determine the expression of matrix metalloproteinases (MMPs)-2, -7 and -9 and beta-catenin in uterine serous carcinoma (USC) and endometrioid endometrial carcinoma (EEC) and to investigate any difference in expression between EEC and USC which might explain the mechanism of invasion and aggressive behaviour of USC. METHODS AND RESULTS: Tissue microarrays were created from the viable central part and from the invasive edge of 20 cases of grade 3 EEC and 73 cases of USC. Immunohistochemistry was performed using antibodies to MMPs-2, -7 and -9 and beta-catenin. MMPs-2, -7 and -9 and beta-catenin were present in both tumour types; there was significantly higher expression of MMPs-2 and -9 in EEC compared with USC and significantly increased expression of MMPs-2 and -9 by carcinoma cells at the invasive edge of USC. CONCLUSIONS: MMPs-2, -7 and -9 and beta-catenin are present in EEC and USC. The increased expression of MMPs-2 and -9 by carcinoma cells at the invasive edge of USC is possibly due to increased binding of MMPs secreted by the stromal cells to carcinoma cells, thus equipping the USC carcinoma cells with proteases for invasion.  相似文献   
64.
Purpose: The purpose of this study was to evaluate the influence of serous retinal detachment (SRD) on the outcome of intravitreal ranibizumab (IVR) therapy in diabetic macular oedema (DME).

Materials and methods: Fifty-one eyes with cystoid macular oedema (CME) and SRD (study group) and 57 eyes with only CME (control group) that received pro re nata (PRN) IVR injections during a 6-month period were retrospectively evaluated. The outcome measures included changes in the central macular thickness (CMT) and best corrected visual acuity (BCVA) and injection numbers.

Results: The mean initial CMT in the study and control groups was 467?±?101 and 440?±?89?µm, respectively. The mean BCVA in the study and control groups was 0.75?±?0.38 and 0.59?±?0.36 logarithm of minimal angle of resolution (LogMAR), respectively (p?=?0.010). The study group received a mean of 2.2?±?0.92 injections, whereas the control group received a mean of 2.54?±?0.9 injections. The decrease in CMT was greater, but not significantly greater, in the study group than in the control group.

Conclusion: The presence of SRD resulted in a less favourable visual acuity (VA) outcome with IVR. Disruption of the ellipsoid zone and abnormality of the foveal avascular zone at the baseline examination were correlated with a lower VA. Both of the pathologies occurred more frequently in the SRD group.  相似文献   
65.
《Surgery (Oxford)》2022,40(4):249-257
As the use of cross-sectional imaging has become more frequent, there has been an increase in the diagnosis of cystic neoplasms and small non-functioning neuroendocrine neoplasms within the pancreas. Investigation and follow-up of cystic lesions of the pancreas requires a multimodal approach, of which endoscopic ultrasound with biopsy is becoming an increasingly important component. The main premalignant cystic neoplasms of the pancreas are mucinous-type tumours, intraductal papillary mucinous neoplasm (IPMN) and mucinous cystic neoplasm (MCN). Main-duct IPMN should be resected due to the high incidence of underlying malignancy; however, a selective approach to intervention for side-branch IPMN should be taken (dependent on the presence of symptoms, tumour markers and tumour characteristics). Pancreatic neuroendocrine neoplasms (PanNENs) can also present as cystic lesions in approximately 18% of cases. Biochemically confirmed functional PanNEN and non-secreting PanNENs larger than 2 cm in size should be evaluated for surgery.  相似文献   
66.
67.
目的 探讨非损伤阈值下微脉冲激光(subthreshold micropulse laser,SML)治疗慢性中心性浆液性脉络膜视网膜病变(central serous chorioretinopathy,CSCR)的疗效与安全性。方法 前瞻性非随机病例对照研究。慢性CSCR患者60例(60眼),分为3组:非治疗观察(non-therapeutic observation,NTO)组、光动力疗法(photodynamic therapy,PDT)组、SML组,每组20例(20眼)。通过光学相干断层扫描血管成像、自发荧光、黄斑完整评估仪等获取研究前后患眼的最佳矫正视力(best corrected visual acuity,BCVA)、视网膜敏感度(retinal sensitivity,RS)、视网膜下液(subretinal fluid,SRF)高度及消失时间、中心黄斑厚度(central macular thickness,CMT)、黄斑中心凹下脉络膜厚度(subfoveal choroidal thickness,SFCT)、脉络膜毛细血管血流面积(choriocapillaris flow area,CFA)等数据以及评估椭圆体带、视网膜色素上皮(retinal pigment epithelium,RPE)等损伤。结果 NTO组仅4眼SRF消失,消失时间为(2.98±0.34)个月;PDT组患眼经(1.25±0.44)次PDT治疗后SRF均消失,消失时间为(1.87±1.32)个月;SML组患眼经(2.70±1.63)次治疗后SRF均消失,消失时间为(3.50±2.06)个月,PDT组与SML组治疗次数及SRF消失时间相比差异均有统计学意义(均为P<0.05)。末次随访时,NTO组BCVA、RS稍改善,CMT、SCFT及CFA均较入组时下降,但末次随访时NTO组上述指标与PDT组、SML组比较差异均有统计学意义(均为P<0.05);PDT组、SML组BCVA、RS及CFA均较治疗前明显改善,CMT与SCFT均较治疗前下降,两治疗组间各指标比较差异均无统计学意义 (均为P>0.05)。NTO组持续存在椭圆体带损伤,PDT组、SML组椭圆体带形态均改善,自发荧光均未见明显变化,均未见脉络膜新生血管,SML组未见滴定激光斑点。结论 慢性CSCR积极治疗可以避免黄斑结构与功能进一步损伤;SML治疗与PDT治疗结果类似,均能有效改善慢性CSCR患眼视功能与恢复视网膜形态结构,但SML治疗次数相对较多、恢复时间相对较长。  相似文献   
68.
Background: The aim of this study was to evaluate the differences, in terms of visual outcome and treatment needs, between smokers and non-smokers central serous chorioretinopathy (CSCR) patients.

Methods: The files of 252 patients diagnosed with CSCR who had presented to the Retina Unit of the Ophthalmology Clinic at Dicle University Medical School in Turkey were retrospectively evaluated. Eighty-four smokers, with a known history of smoking of at least one pack-year, and 133 non-smokers were included, whereas 35 patients with additional pathologies were excluded from the study.

Results: Of the patients, 192 (88.5%) were male and 25 (11.5%) were female. The mean patient age was 38.8?±?8.1 years (range: 20–68 years). Visual acuity (VA) of the smoker and non-smoker groups was measured as 0.45?±?0.35 and 0.24?±?0.28 logarithm of the minimum angle of resolution (logMar), respectively, at the first visit; 0.19?±?0.29 and 0.06?±?0.14 logMar at the sixth month; and 0.07?±?0.14 and 0.02?±?0.05 logMar at the ninth month. VA measurements at presentation and during all examinations (1th, 6th and 9th month) were significantly different for the two groups. VA was lower in the smoker group. In 27 patients (12.4%), an additional treatment modality was needed. Of the 27 patients, only 8 (6%) were non-smokers, whereas 19 (22.6%) were smokers. There was no difference between groups in the recurrence rate during follow-up (p?=?0.907); 14 (16.7%) smokers and 8 (19.0%) non-smokers experienced a recurrence.

Conclusion: This study has shown that patients selected and who are current smokers have poorer vision and need longer treatment.  相似文献   
69.
70.
目的评价激光光凝眼底联合卵磷脂络合碘片治疗中心性浆液性脉络膜视网膜病变(CSC)的疗效。方法将198例CSC患者212眼根据患者自愿分为两组各99例106眼。对照组采用激光光凝眼底治疗,观察组采用激光光凝眼底联合卵磷脂络合碘片治疗。在治疗1个月和3个月后用Amsler方格表评价视力恢复状况,并比较两组疗效。结果两组治疗后视力较之治疗前明显改善(P<0.05)。观察组治疗1月后视力恢复状况明显好于对照组(P<0.05),3月后两组视力无统计学差异(P>0.05)。观察组总显效率与对照组相比有统计学差异(P<0.05),但总有效率组间无统计学差异(P>0.05)。结论激光光凝眼底联合卵磷脂络合碘片治疗CSC可以帮助患者尽快改善视力状况,提升治疗总显效率,是一种较为理想的治疗手段,值得在临床中推广运用。  相似文献   
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