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oe1(光电查) - 科学论文

43 条数据
?? 中文(中国)
  • An update on inflammatory choroidal neovascularization: epidemiology, multimodal imaging, and management

    摘要: Inflammatory choroidal neovascular membranes are challenging to diagnose and manage. A number of uveitic entities may be complicated by the development of choroidal neovascularization leading to a decrease in central visual acuity. In conditions such as punctate inner choroidopathy, development of choroidal neovascularization is extremely common and must be suspected in all cases. On the other hand, in patients with conditions such as serpiginous choroiditis, and multifocal choroiditis, it may be difficult to differentiate between inflammatory choroiditis lesions and choroidal neovascularization. Multimodal imaging analysis, including the recently introduced technology of optical coherence tomography angiography, greatly aid in the diagnosis and management of inflammatory choroidal neovascularization. Management of these neovascular membranes consists of anti-vascular growth factor agents, with or without concomitant anti-inflammatory and/or corticosteroid therapy.

    关键词: Posterior uveitis,angiography,Choroiditis,Uveitis,Fluorescein angiography,Optical coherence tomography angiography,EDI-OCT,Indocyanine green,Inflammatory choroidal neovascularization

    更新于2025-09-09 09:28:46

  • Collateral vessels on optical coherence tomography angiography in eyes with branch retinal vein occlusion

    摘要: Aims To detect collateral vessels using optical coherence tomography angiography (OCTA) in eyes with branch retinal vein occlusion (BRVO) and to investigate the associations with visual outcomes and macular oedema. Methods Eyes with macular oedema secondary to BRVO that underwent OCTA at baseline and were followed up for more than 6 months were enrolled. The presence of collaterals, whether the collaterals were leaky or not, and the associations with visual outcomes and macular oedema were investigated. results Twenty-eight eyes of 28 patients (8 men and 20 women; mean age, 68 years) were enrolled. Collaterals were detected in 23 eyes (82%) and already existed at the initial visit. Collaterals were more frequently detected in eyes with major BRVO or ischaemic type. One-third of the collaterals were leaky and all of the leaky collaterals had microaneurysms (MAs) inside. Macular oedema in eyes with collaterals was more quickly and frequently resolved than that in eyes without collaterals, but there were no significant differences. Collateral vessel formation did not seem to impact on visual outcomes, but the mean baseline central retinal thickness (CRT) was significantly higher in eyes with collaterals, and the mean CRT reduction at 6 months after treatments was significantly greater than in eyes without collaterals. Conclusions These results suggest that collateral vessels are formed at the acute phase in eyes with BRVO. In addition, the presence of collaterals might be associated with absorption of macular oedema, but MAs formed in collaterals sometimes can cause macular oedema.

    关键词: visual outcomes,collateral vessels,branch retinal vein occlusion,optical coherence tomography angiography,macular oedema

    更新于2025-09-09 09:28:46

  • [IEEE 2018 24th International Conference on Pattern Recognition (ICPR) - Beijing, China (2018.8.20-2018.8.24)] 2018 24th International Conference on Pattern Recognition (ICPR) - Early Diagnosis of Diabetic Retinopathy in OCTA Images Based on Local Analysis of Retinal Blood Vessels and Foveal Avascular Zone

    摘要: This paper introduces a diagnosis system for detecting early signs of diabetic retinopathy (DR) using optical coherence tomography angiography (OCTA) images. We developed a segmentation technique that was able to extract blood vessels from both retinal superficial and deep maps. It is based on a higher order joint Markov-Gibbs random field (MGRF) model, which combines both current and spatial appearance information of retinal blood vessels. To be able to train/test a support vector machine (SVM) classifier, three local features were extracted from the segmented images. These extracted features are the density and appearance of the retinal blood vessels in addition to the distance map of the foveal avascular zone (FAZ). Then, we used SVM with linear kernel to distinguish sub-clinical DR patients from normal cases. By using 105 subjects, the presented computer-aided diagnosis (CAD) system demonstrated an overall accuracy (ACC) of 97.3% and a Dice similarity coefficient (DSC) of 97.9%.

    关键词: Markov-Gibbs random field,support vector machine,diabetic retinopathy,optical coherence tomography angiography,computer-aided diagnosis

    更新于2025-09-09 09:28:46

  • Changes in Ganglion Cell-Inner Plexiform Layer Thickness and Retinal Microvasculature in Hypertension: An OCT Angiography Study

    摘要: Objective: To investigate retinal blood flow in patients with hypertension using optical coherence tomography angiography (OCTA) and the relationship between blood flow metrics and ganglion cell-inner plexiform layer (GC-IPL) thickness. Design: Retrospective, cross-sectional study. Methods: A total of 201 eyes from 117 healthy subjects and 84 hypertensive patients without any ocular abnormalities were included. Hypertensive patients were divided into the two groups according to disease periods (<5 years: hypertension group 1; ≥5 years: hypertension group 2). Macular 3 × 3 mm angiography was acquired using the Zeiss Cirrus 5000 OCT instrument. Vessel density (VD), perfusion density (PD), and foveal avascular zone metrics of the superficial capillary plexus were automatically calculated, and the thicknesses of the central fovea, GC-IPL, and peripapillary retinal nerve fiber layer (RNFL) were measured. All measurements were compared among the three groups, and retinal blood flow metrics were correlated with the thickness of each retinal layer. Logistic regression analyses were performed to determine the factors associated with prolonged hypertension. Results: The average GC-IPL (p<0.001) and peripapillary RNFL (p=0.048) thicknesses in hypertension group 2 were significantly thinner compared to the control group. The 3 mm total area of the VD and PD was also decreased compared to the control group and hypertension group 1 (all p<0.05), and was significantly correlated with the GC-IPL (VD: r=0.450, p=0.001; PD: r=0.467, p<0.001) and peripapillary RNFL (VD: r=0.314, p=0.027; PD: r=0.328, p=0.023) thicknesses in hypertension group 2. Using multivariate logistic analyses, only the average GC-IPL thickness was a significant factor for prolonged hypertension (odds ratio=0.911, p=0.002). Conclusions: In patients with hypertension lasting more than 5 years, inner retinal layer thinning, particularly GC-IPL thinning, was observed, which was significantly correlated with a decrease in retinal blood flow. Therefore, physicians should consider the effects of hypertension on the GC-IPL.

    关键词: hypertension,retinal microcirculation,optical coherence tomography angiography,ganglion cell-inner plexiform layer

    更新于2025-09-09 09:28:46

  • Optical Coherence Tomography Angiography in Familial Exudative Vitreoretinopathy: Clinical Features and Phenotype-Genotype Correlation

    摘要: PURPOSE. To evaluate the microstructure of the fovea in patients with familial exudative vitreoretinopathy (FEVR) compared to healthy controls using optical coherence tomography angiography (OCTA). METHODS. In this consecutive, cross-sectional, observational case series, 41 eyes of 41 patients diagnosed as FEVR and 37 eyes in 37 control subjects were studied. OCTA was utilized to automatically measure the foveal avascular zone (FAZ) and the vessel density (VD). Inner retinal thicknesses (IRT) and central retinal thickness (CRT) were measured with the instrument caliper. Targeted next-generation sequencing was performed, and phenotype-genotype association was analyzed. RESULTS. Small FAZ was found in 31.70% (13/41) FEVR eyes but not in controls. Greater CRT and lower super?cial foveal VD were noted in FEVR patients. FAZ is negatively correlated with IRT. Persistence of the inner retinal layer (IRL) in fovea was present in 48.78% (20/41) FEVR eyes but not found in controls. Zero percent (0/10) of patients with the low-density lipoprotein receptor-related protein 5 (LRP5) mutation, 50% (1/2) with the frizzled-4 (FZD4) mutation, and 66.67% (3/4) with the tetraspanin-12 (TSPAN12) mutation had preserved foveal IRL and small FAZ. CONCLUSIONS. Our data indicate FEVR status is associated with a signi?cantly smaller FAZ, decreased vascular density in both the super?cial and deep layers of parafoveal area, a thicker fovea, and an abnormally preserved IRL in fovea. In addition, patients with the LRP5 mutation had a milder phenotype than those with the FDZ4 or TSPAN12 mutations. These novel ?ndings could provide insight into the understanding of the pathogenesis of FEVR.

    关键词: phenotype-genotype correlation,optical coherence tomography angiography,familial exudative vitreoretinopathy

    更新于2025-09-09 09:28:46

  • Analysis of Foveal Microvascular Structures Using Optical Coherence Tomography Angiography in Age-stratified Healthy Koreans

    摘要: Purpose: To evaluate foveal avascular zone (FAZ) microvascular structural changes in healthy Korean subjects stratified by age using optical coherence tomography angiography (OCTA). Methods: Eighty eyes of 43 healthy volunteer subjects who had 20/20 or better best corrected visual acuity without other ocular or systemic disease except vitreous floaters and dry eye syndrome were enrolled and stratified by age group. To measure FAZ size and vascular density (VD) of the superficial capillary plexus (SCP) and deep capillary plexus (DCP), OCTA (DRI OCT Triton, Swept Source OCT, Topcon, Tokyo, Japan) scans were performed over fovea-centered 3 × 3 mm2 regions, and then compared with central macular thickness (CMT) and subfoveal choroidal thickness. Results: Mean age of the participants was 46.4 ± 16.1 (20–78). The SCP and DCP FAZ sizes were 0.32 ± 0.11 mm2 and 0.41 ± 0.14 mm2, respectively. There was a significant difference by age group (p < 0.001, p < 0.001), respectively. The FAZ VD for SCP and DCP was 28.96 ± 3.05% and 33.15 ± 3.64%, respectively. There was no difference between age groups (p = 0.118, p = 0.637). Univariate and multiple linear regression analysis showed that the FAZ size of SCP and DCP was significantly correlated with age (p = 0.039, p = 0.002) and CMT (p = 0.007, p = 0.013), respectively. The SCP and DCP FAZ size were positively correlated with age (R2 = 0.279, p < 0.001, R2 = 0.344, p < 0.001), and negatively correlated with CMT (R2 = 0.354, p < 0.001, R2 = 0.285, p < 0.001), respectively. Conclusions: The FAZ size of SCP and DCP increased with age and were negatively correlated with CMT. These results suggest that consideration of age and CMT is important when performing the clinical evaluation of FAZ size in healthy subjects.

    关键词: Healthy subjects,Foveal avascular zone,Vascular density,Age,Optical coherence tomography angiography

    更新于2025-09-09 09:28:46

  • Repeatability and Reproducibility of Quantification of Superficial Peri-papillary Capillaries by four Different Optical Coherence Tomography Angiography Devices

    摘要: This study was performed to test the repeatability and reproducibility of measurements of peri-papillary capillaries from four optical coherence tomography angiography (OCTA) devices. 109 healthy eyes were imaged with four OCTA devices (Spectralis, Optovue, Triton and Cirrus). A 3 × 3 mm scan pattern centered on the disc was repeated twice by each device. En face images of superficial capillary plexus were screened and processed for calculation. Vessel length density (VLD) was calculated on four equally divided parts of a ring between two concentric circles manually centered on the disc. General linear model (GLM) was used to test the impact of device and location on VLD. Intraclass correlation coefficient (ICC) of VLD between repeated scans was calculated. Of 218 acquisitions, 36%, 92%, 76% and 88% were eligible for analysis from Spectralis, Optovue, Triton and Cirrus, respectively. ICC was 0.94, 0.90, 0.84 and 0.87 for the four devices. GLM showed measurements significantly varied among devices (P < 0.001) and locations (P < 0.001). Pairwise comparison showed Triton = Spectralis >Optovue >Cirrus, and temporal = nasal >superior = inferior in measuring capillary VLD. This study revealed the repeatability of measuring peri-papillary capillaries was high for all four devices, while the reproducibility among the machines was unfavorable.

    关键词: optical coherence tomography angiography,vessel length density,peri-papillary capillaries,reproducibility,repeatability

    更新于2025-09-09 09:28:46

  • Abnormal choroidal flow on optical coherence tomography angiography in central serous chorioretinopathy

    摘要: Importance: Analyzing choroidal flow in central serous chorioretinopathy (CSC) with novel device Background: To examine the abnormal morphology of choriocapillary flow with optical coherence tomography angiography (OCTA) according to the presence of subretinal fluid (SRF) in CSC. Design: A hospital-based retrospective study Participants: We analyzed OCTA results of 68 eyes (68 patients) diagnosed as CSC with or without SRF (active and resolved CSC, respectively) at the Asan Medical Center. Methods: We classified OCTA choriocapillary images into three pattern groups: mixed perfusion, hyper-perfusion, and normal perfusion. Data analysis included age, follow-up duration, treatment modalities, number of treatments, subfoveal choroidal thickness, and SRF height. Main outcome measure: The relationship between CSC activity and choriocapillary pattern Results: Abnormal choroidal flow (mixed and hyper-perfusion) was more frequently found in eyes with active CSC (100%) than resolved CSC (47.5%, p < 0.001). In active CSC eyes, mixed perfusion was predominant (71.4%), while hyper-perfusion was predominant in those with resolved CSC (73.7%). Eyes with recently resolved CSC (SRF absorption present for <2 months) had abnormal choriocapillary flow more often than the remaining eyes with resolved CSC (83.3% vs. 32.1%, p = 0.005). Resolved CSC eyes with abnormal choriocapillary flow demonstrated more recurrence than eyes with normal choriocapillary flow (42.1% vs 9.5%, p = 0.017). Conclusions and Relevance: The pattern of choriocapillary flow abnormalities on OCTA can indicate CSC disease activity. Because eyes with resolved CSC showing abnormal choroidal flow have a high recurrence rate, they should be carefully followed-up.

    关键词: Abnormal choroidal flow,central serous chorioretinopathy,optical coherence tomography angiography

    更新于2025-09-09 09:28:46

  • Evaluation of vascular changes in intermediate uveitis and retinal vasculitis using swept-source wide-field optical coherence tomography angiography

    摘要: Purpose To evaluate vascular changes in patients with intermediate uveitis with or without retinal vasculitis using swept-source wide-field optical coherence tomography angiography (OCTA). Methods This is a prospective cross-sectional study. Consecutive patients with intermediate uveitis were evaluated using wide-field OCTA. Wide-field OCTA and en-face OCT images were analysed for the presence of capillary non-perfusion and reduced perfusion, disruption of ellipsoid zone, and abnormalities on en-face wide-field retinal thickness maps, respectively, and compared with fluorescein angiography (FA) findings in a subcohort. results 164 eyes of 88 patients with intermediate uveitis were included. Areas of capillary non-perfusion and reduced perfusion were more frequently observed in the choroidal OCTA slab (33.3% and 49.4%), choriocapillaris (CC; 31.4% and 48%) and deep capillary plexus (DCP; 9.6% and 34.6%) than in the superficial capillary plexus (SCP; 5% and 26.3%), respectively. Intermediate uveitis with vasculitis presented more frequently with non-perfusion and hypoperfusion in the DCP (p=0.003 and p=0.05, respectively) and SCP (p=0.007 and p=0.005, respectively) than intermediate uveitis without vasculitis. Peripheral capillary leakage on FA correlated with the presence of perivascular, macular and generalised thickening on en-face wide-field thickness maps (p=0.007). Ischaemia on FA was significantly associated with non-perfusion on wide-field OCTA in SCP and DCP (p=0.019 and p=0.027, respectively). Conclusion Changes in the choroid, CC and DCP are more frequently found than in the SCP on wide-field OCTA in intermediate uveitis. While wide-field OCTA is a reliable tool to detect capillary non-perfusion in intermediate uveitis, it was not helpful in determining disease activity. Trial registration number NCT02811536.

    关键词: vascular changes,swept-source wide-field optical coherence tomography angiography,retinal vasculitis,intermediate uveitis

    更新于2025-09-09 09:28:46

  • Inter-relationship between retinal and choroidal vasculatures using optical coherence tomography angiography in normal eyes

    摘要: Purpose: To quantify vascular and structural macular variables in healthy eyes and to investigate correlations between these variables and age using optical coherence tomography angiography. Materials and methods: A total of 261 eyes of 261 subjects with normal fundus were included. Central macular thickness, ganglion cell layer to inner plexiform layer thickness, outer retina layer thickness, subfoveal choroidal thickness, and choroidal vascularity index were measured using optical coherence tomography. Foveal avascular zone area, vascular density, and flow void area were measured using optical coherence tomography angiography. Results: Vascular density in the superficial capillary plexus was correlated with central macular thickness, ganglion cell layer to inner plexiform layer thickness, and outer retina layer thickness (P < 0.001, P = 0.004, and P < 0.001, respectively). Vascular density in the deep capillary plexus was correlated with central macular thickness and outer retina layer thickness (P = 0.003 and P = 0.001, respectively). Vascular density of choriocapillaris was correlated with vascular density of superficial capillary plexus and deep capillary plexus (P < 0.001 and P = 0.001, respectively). Conclusion: Vascular density of choriocapillaris varies with retinal vascular density rather than the structure of choroid using optical coherence tomography angiography. In contrast, retinal vascular density changes as the retinal structure. Our results provide more information about the relationship between retina and choroid.

    关键词: choroidal vessels,optical coherence tomography,optical coherence tomography angiography,Retinal vessels,normal eye

    更新于2025-09-04 15:30:14