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oe1(光电查) - 科学论文

4 条数据
?? 中文(中国)
  • Quantitative measurement of vascular density and flow using optical coherence tomography angiography (OCTA) in patients with central retinal vein occlusion: Can OCTA help in distinguishing ischemic from non-ischemic type?

    摘要: Background: To evaluate microvascular changes and quantitative parameters in patients with central retinal vein occlusion (CRVO) by using optical coherence tomography angiography (OCTA) and finding difference between presumably ischemic and non ischemic CRVO. Methods: Patients with CRVO (31) and healthy control (20) were enrolled in this observational case control study. The OCTA was done for each patient and control subject. In macular area 2 images were taken for each eye (3 × 3 mm and 8 × 8 mm). The images were analyzed at three capillary plexuses (superficial and deep retinal capillary layers and choriocapillaris layer). Results: Thirty-one patients with CRVO (mean age 60.00 ± 13.72 years) and 20 healthy age/gender matched subjects (mean age 54.10 ± 12.33 years) were enrolled in this study (p = 0.095). The mean visual acuity of patients was 0.47 ± 0.54 LogMAR. Eyes with CRVO as compared with fellow eyes and control group showed significant reduction of flow in superficial (1.171 ± 0.262 vs. 1.362 ± 0.285 vs. 1.453 ± 0.105) and deep capillary plexus (1.042 ± 0.402 vs. 1.331 ± 0.315 vs. 1.526 ± 0.123) and choriocapillaris (1.206 ± 0.543 vs. 1.841 ± 0.308 vs. 1.966 ± 0.05) and vascular density in superficial (45.92 ± 4.2 vs. 50.99 ± 4.35 vs. 52.85 ± 2.99) and deep (48.03 ± 4.71 vs. 55.86 ± 3.81 vs. 58.2 ± 2.65) capillary plexuses. Some parameters (flow of both retinal capillary plexuses and parafoveal vascular density in deep plexus) showed significantly reduction in fellow eyes than control group. The parameters including flow [superficial (1.014 ± 0.264 vs. 1.279 ± 0.19) and deep (0.873 ± 0.442 vs. 1.152 ± 0.32) capillary plexuses and choriocapillaris (0.79 ± 0.327 vs. 1.424 ± 0.51)] and vascular density [superficial (44.24 ± 2.13 vs. 46.58 ± 4.13) and deep (45.28 ± 3.5 vs. 49.32 ± 3.94) capillary plexuses] were lower significantly in ischemic type than non ischemic CRVO. The most damaged parameter was flow in deep capillary plexus. The model with smallest Akaike information criterion and Bayesian information criterion was chosen as the best model. For easier calculation, we also calculated the reduced model. By choosing the threshold of 12.6, the formula [3.9 × F1S + 0.8 × F3S] can diagnose the presumably ischemic CRVO from non ischemic type with AUC of 0.84, sensitivity of 100% and specificity of 69%. (F1S: flow in the central 1 mm-radius-circle of superficial plexus and F3S: flow in the central 3 mm-radius-circle of superficial plexus). Conclusion and relevance: In CRVO patients, the OCTA can accurately evaluate changes in microvascular structures. It may help in differentiation ischemic CRVO from non-ischemic CRVO.

    关键词: Ischemic,Non-ischemic,Central retinal vein occlusion,Optical coherence tomography angiography

    更新于2025-09-23 15:23:52

  • Baseline characteristics associated with early visual acuity gains after ranibizumab treatment for retinal vein occlusion

    摘要: Background: To identify baseline patient characteristics associated with early clinically significant visual acuity (VA) improvements within 3 months of treatment initiation in ranibizumab-treated patients with retinal vein occlusion (RVO) in the SHORE study. Methods: Post hoc analysis of baseline patient characteristics in the randomized, open-label, vision examiner–masked SHORE phase 4 study that compared monthly versus pro re nata dosing of ranibizumab in patients with branch and central RVO. Patients who enrolled in SHORE fulfilled eligibility criteria per protocol (N = 202). SHORE data were retrospectively analyzed to identify baseline patient characteristics associated with early clinically significant improvements in VA, defined as improvement to a Snellen equivalent of 20/40 or better vision (≥ 69 Early Treatment Diabetic Retinopathy Study [ETDRS] letters) or an increase in best-corrected VA (BCVA) of 15 or more ETDRS letters from baseline within 3 months of treatment initiation. Main outcome measures were BCVA gain of 15 or more ETDRS letters from baseline, Snellen equivalent of 20/40 or better vision, and baseline factors associated with early clinically significant improvement in BCVA. Results: The median time for patients to achieve a BCVA of 20/40 or better was 59 days and the median time for patients to gain 15 or more ETDRS letters was 63 days. Better baseline BCVA (> 50 ETDRS letters/Snellen equivalent ≥ 20/100), greater baseline total macular volume (> 9.99 mm3), and presence of subretinal fluid at baseline were all associated with early improvement to 20/40 or better vision (ETDRS equivalent ≥ 69 letters; P < .0001, P = .02, and P = .03, respectively). Conclusions: This retrospective analysis found that better BCVA, greater total macular volume, and presence of subretinal fluid at baseline were associated with more rapid vision gains. Clinicians may find these helpful when considering the likelihood of achieving early clinically significant VA improvements with ranibizumab in patients with RVO.

    关键词: Ranibizumab,Branch retinal vein occlusion,Central retinal vein occlusion,CRVO,BRVO,Retinal vein occlusion,Anti-VEGF,RVO

    更新于2025-09-23 15:22:29

  • Disorganization of Retinal Inner Layers and Ellipsoid Zone Disruption Predict Visual Outcomes in Central Retinal Vein Occlusion

    摘要: To assess the associations and predictive value of spectral-domain (SD) OCT inner and outer retinal structural parameters and visual acuity (VA) outcomes in macular edema (ME) secondary to central retinal vein occlusion (CRVO).

    关键词: disorganization of retinal inner layers,visual acuity,ellipsoid zone disruption,macular edema,spectral-domain OCT,central retinal vein occlusion

    更新于2025-09-23 15:21:01

  • Deep Neural Network-Based Method for Detecting Central Retinal Vein Occlusion Using Ultrawide-Field Fundus Ophthalmoscopy

    摘要: The aim of this study is to assess the performance of two machine-learning technologies, namely, deep learning (DL) and support vector machine (SVM) algorithms, for detecting central retinal vein occlusion (CRVO) in ultrawide-field fundus images. Images from 125 CRVO patients (n = 125 images) and 202 non-CRVO normal subjects (n = 238 images) were included in this study. Training to construct the DL model using deep convolutional neural network algorithms was provided using ultrawide-field fundus images. The SVM uses scikit-learn library with a radial basis function kernel. The diagnostic abilities of DL and the SVM were compared by assessing their sensitivity, specificity, and area under the curve (AUC) of the receiver operating characteristic curve for CRVO. For diagnosing CRVO, the DL model had a sensitivity of 98.4% (95% confidence interval (CI), 94.3–99.8%) and a specificity of 97.9% (95% CI, 94.6–99.1%) with an AUC of 0.989 (95% CI, 0.980–0.999). In contrast, the SVM model had a sensitivity of 84.0% (95% CI, 76.3–89.3%) and a specificity of 87.5% (95% CI, 82.7–91.1%) with an AUC of 0.895 (95% CI, 0.859–0.931). Thus, the DL model outperformed the SVM model in all indices assessed (P < 0.001 for all). Our data suggest that a DL model derived using ultrawide-field fundus images could distinguish between normal and CRVO images with a high level of accuracy and that automatic CRVO detection in ultrawide-field fundus ophthalmoscopy is possible. This proposed DL-based model can also be used in ultrawide-field fundus ophthalmoscopy to accurately diagnose CRVO and improve medical care in remote locations where it is difficult for patients to attend an ophthalmic medical center.

    关键词: ultrawide-field fundus ophthalmoscopy,support vector machine,deep learning,central retinal vein occlusion,machine learning

    更新于2025-09-09 09:28:46