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Vascular and structural alterations of the choroid evaluated by optical coherence tomography angiography and optical coherence tomography after half-fluence photodynamic therapy in chronic central serous chorioretinopathy
摘要: Purpose To concurrently evaluate the effect of half-fluence photodynamic therapy (hf PDT) on choriocapillaris (CC) perfusion and choroidal structure in chronic central serous chorioretinopathy (CSC). Methods This prospective study included 48 eyes of 41 patients with chronic CSC. Enhanced depth imaging optical coherence tomography and optical coherence tomography angiography (OCTA) images were analyzed. Choroidal area (CA), luminal area (LA), and stromal area (SA) were computed using Image J software. Results One month after hf-PDT, total CA decreased to 1.312 mm2 from 1.490 mm2 (p < 0.001), LA decreased to 0.981 mm2 from 1.097 mm2 (p < 0.001), and SA decreased to 0.331 mm2 from 0.393 mm2 (p < 0.001). In OCTA, the CC flow in the eyes with CSC (17.75 mm2) was statistically significantly lower than the fellow eyes (18.93 mm2) at the baseline visit (p < 0.001). After hf-PDT, the flow in the choriocapillaris statistically significantly increased to 18.81 mm2 at the first month (p = 0.02). Conclusions OCTA proves that after hf-PDT a significant increase in CC perfusion occurred at first month. The decrease of the luminal areas in enhanced depth imaging optical coherence tomography is mainly due to a decrease in large-caliber vessels, which indicates that hf-PDT has an effect on larger choroidal vessels and spares CC flow.
关键词: Chronic central serous chorioretinopathy,Optical coherence tomography angiography,Half-fluence photodynamic therapy,Choriocapillaris perfusion
更新于2025-09-23 15:23:52
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Fundus autofluorescence and spectral domain optical coherence tomography as predictors for long-term functional outcome in rhegmatogenous retinal detachment
摘要: Purpose To detect pre- and postoperative retinal changes in fundus autofluorescence (AF) and spectral domain optical coherence tomography (SD-OCT) and to correlate these with functional outcome in patients with primary rhegmatogenous retinal detachment (RRD). Methods A prospective, 30-month study of patients operated with 25-gauge vitrectomy for primary RRD. Patients were examined preoperatively and after 6 and 30 months, using ultrawide-field AF images (UWFI) (Optos 200Tx) and SD-OCT (Topcon 3D OCT-2000) imaging. Results Of 84 patients (84 eyes) included at baseline, 100.0 and 86.9% were re-examined at month 6 and 30, respectively. Preoperative findings such as macular attachment, detachment > 750 μm from foveola, lack of intraretinal separation, and subfoveal elevation ≤ 500 μm were all associated with better BCVA at months 6 and 30. Postoperative disruption of the photoreceptor layer was associated with poor BCVA at month 6 (p < 0.001) but not at month 30. At baseline, AF-demarcation of RRD was demonstrated by a hyperfluorescent edge in 92.0% and was associated with visual impairment at months 6 (p = 0.003) and 30 (p = 0.003). Visual outcome at month 30 was good (≤ 0.3 logMAR (≥ 20/40 Snellen)), regardless of the preoperative, macular status. However, with significantly better visual outcome in patients with macula attachments versus partly or totally macular detachments (p < 0.001). Conclusion Fundus AF and SD-OCT is able to identify retinal reestablishment up to 30 months after primary RRD, with good correlation to BCVA. These findings emphasize the importance of long-term studies for final visual recovery.
关键词: Fundus autofluorescence,Rhegmatogenous retinal detachment,Long-term outcome,Vitrectomy,Visual outcome,Optical coherence tomography
更新于2025-09-23 15:23:52
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Impact of segmentation density on spectral domain optical coherence tomography assessment in Stargardt disease
摘要: Purpose Automated spectral domain optical coherence tomography (SD-OCT) segmentation algorithms currently do not perform well in segmenting individual intraretinal layers in eyes with Stargardt disease (STGD). We compared selective B-scan segmentation strategies for generating mean retinal layer thickness and preserved area data from SD-OCT scans in patients with STGD1. Methods Forty-five eyes from 40 Stargardt patients were randomly selected from the ongoing Natural History of the Progression of Atrophy Secondary to Stargardt Disease (ProgStar) study. All eyes underwent SD-OCT using a standard macular volume consisting of 1024 × 49 equally spaced B-scans within a 20 × 20 degree field centered on the fovea. All 49 B-scans were segmented manually to quantify total retina, outer nuclear layer (ONL), photoreceptor inner segments, photoreceptor outer segments (OS), and retinal pigment epithelial layer (RPE). Mean thickness and total area were generated using all 49 B-scans (spaced 122 μm apart), 25 B-scans (every other B-scan, spaced 240 μm apart), 17 B-scans (every third scan, 353 μm apart), and 13 B-scans (every fourth scan, 462 μm apart), as well as by using an Badaptive^ method where a subset (minimum 25 B-scans) of B-scans that the grader deemed as significantly different from adjacent B-scans were utilized. Mean absolute and percentage errors were calculated for macular thickness and area of different retinal layers for the different B-scan subset selection strategies relative to using all 49 B-scans, which was considered the reference or ground truth. Results Mean thickness and area measurements were significantly different for any regularly spaced reduction in B-scan density relative to the ground truth. When an adaptive approach was applied using a minimum of half the scans, the differences relative to ground truth were no longer significantly different. The mean percent differences for the area and thicknesses of the various layers ranged from 0.02 to 33.66 (p < 0.05 for all comparisons) and 0.44 to 7.24 (p > 0.05) respectively. Conclusion Manual segmentation of a subset of B-scans using an adaptive strategy can yield thickness and area measurements of retinal sublayers comparable to the reference ground truth derived from using all B-scans in the volume. These results may have implications for increasing the efficiency of SD-OCT grading strategies in clinical trials for STGD and other related macular degenerative disorders.
关键词: Stargardt,Segmentation density,Spectral domain optical coherence tomography,Retinal layers
更新于2025-09-23 15:23:52
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Advances in imaging and molecular diagnostics of ocular tuberculosis and selected observations from the Collaborative Ocular Tuberculosis Study (COTS)
摘要: Introduction: Ocular tuberculosis (TB) is a rare extra-pulmonary manifestation with protean clinical manifestations. Ocular TB as a cause of potentially blinding disease has been recently recognized by ophthalmologists as well as pulmonologists. In the past decade, there has been a great leap in our understanding of the disease pathogenesis, clinical and imaging features, as well as therapeutic challenges and disease complications. Areas covered: In this expert review, an emphasis has been laid on the recent advances in ocular imaging including wide-field fundus imaging, fluorescein angiography and autofluorescence, enhanced-depth optical coherence tomography, optical coherence tomography angiography, among others, as well as progress in the field of diagnostics such as polymerase chain reaction and other nucleic acid amplification tests. Findings from the Collaborative Ocular Tuberculosis Study (COTS), a multicentric study on ocular TB, have been explained in details. Expert opinion: Due to rapid advances in the field of fundus imaging and laboratory testing, it has become possible to recognize the pathological alterations observed in ocular TB. With further research, it may be possible to generate a consensus on the diagnosis and management of this entity in the future.
关键词: Tuberculosis,optical coherence tomography,choroiditis,fluorescein angiography,serpiginous-like choroiditis,indocyanine green angiography,uveitis
更新于2025-09-23 15:23:52
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Small HDL subclass is associated with coronary plaque stability: An optical coherence tomography study in patients with coronary artery disease
摘要: BACKGROUND: The role of high-density lipoprotein (HDL) subclasses in atherosclerotic diseases remains an open question. Previous clinical trials have attempted to explore the predictive effect of HDL subspecies on cardiovascular risk. However, no studies have assessed the connections between these subclasses and characteristics of plaque microstructure. OBJECTIVE: To investigate the relationship of HDL subclasses and coronary plaque stability assessed by optical coherence tomography (OCT). METHODS: Morphological characteristics of 160 nontarget lesions from 85 patients with coronary artery disease were assessed by OCT. HDL subclass profiles were analyzed using nondenaturing polyacrylamide gel electrophoresis. RESULTS: The plasma levels of small HDL subclass (percentage or concentration) were found to be positively associated with fibrous cap thickness (r = 0.232, P = .007; r = 0.243, P = .005) and negatively with maximum lipid arc (r = -0.240, P = .005; r = -0.252, P = .003) and lipid core length (r = -0.350, P < .001; r = -0.367, P < .001). Multivariate logistic regression analysis showed the small HDL subclass (percentage or concentration) (odds ratio [OR]: 0.457, 95% confidence interval [CI]: 0.214–0.974, P = .043; OR: 0.438, 95% CI: 0.204–0.938, P = .034) to be an independent factor in predicting OCT-detected thin-cap fibroatheroma of nontarget lesions. CONCLUSION: High levels of small HDL are associated with coronary nontarget plaque stability. Our findings suggest that the small HDL subtype might represent the atheroprotective activity of HDL.
关键词: Atherosclerosis,High-density lipoprotein,Optical coherence tomography,Plaque stability
更新于2025-09-23 15:23:52
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Spectral-domain optical coherence tomography foveal morphology as a prognostic factor for vision performance in congenital aniridia
摘要: Background: Patients with congenital aniridia usually have some degree of foveal hypoplasia, thus representing a limiting factor in the final visual acuity achieved by these patients. The purpose of this study was to analyze whether the foveal morphology assessed by spectral-domain optical coherence tomography may serve as a prognostic indicator for best-corrected visual acuity in congenital aniridia patients. Methods: Observational two-center study performed between January 2012 and March 2017 in the pediatric ophthalmology department at Vissum Alicante and Vissum Madrid, Spain. A total of 31 eyes from 19 patients with congenital aniridia were included. After a complete ophthalmological examination, a high-resolution spectral-domain optical coherence tomography with a three-dimensional scan program macular protocol was used. A morphological grading system of foveal hypoplasia was used varying from grade 1 in which there is a presence of a shallow foveal pit, extrusion of inner retinal layers, outer nuclear layer widening, and a presence of outer segment lengthening to grade 4 in which none of these processes occur. Results: No correlation between central, mid-peripheral, and peripheral macular thickness and logMAR best-corrected visual acuity was found. The presence of outer segment lengthening was associated with better best-corrected visual acuity with a median best-corrected visual acuity, 0.30 logMAR, whereas the absence of this morphologic feature was associated with poorer VA with a median best-corrected visual acuity of 0.61 logMAR (p < 0.001). Conclusion: Foveal hypoplasia morphology can predict the best-corrected visual acuity. Specifically, the morphologic optical coherence tomography feature that is related to a better best-corrected visual acuity in congenital aniridia patients is the presence of outer segment lengthening.
关键词: Congenital aniridia,spectral-domain optical coherence tomography,foveal hypoplasia
更新于2025-09-23 15:23:52
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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
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A Novel Mach-Zehnder Interferometer Using Eccentric-Core Fiber Design for Optical Coherence Tomography
摘要: A novel Mach-Zehnder interferometer using eccentric-core fiber (ECF) design for optical coherence tomography (OCT) is proposed and demonstrated. Instead of the commercial single-mode fiber (SMF), the ECF is used as one interference arm of the implementation. Because of the offset location of the eccentric core, it is sensitive to directional bending and the optical path difference (OPD) of two interference arms can be adjusted with high precision. The birefringence of ECF is calculated and experimentally measured, which demonstrates the polarization sensitivity of the ECF proposed in the paper is similar to that of SMF. Such a structure can replace the reference optical delay line to form an all-fiber passive device. A mirror is used as a sample for analyzing the ECF bending responses of the system. Besides, four pieces of overlapping glass slides as sample are experimentally measured as well.
关键词: Mach-Zehnder interferometer,optical coherence tomography,eccentric core fiber
更新于2025-09-23 15:23:52
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Recovering distance information in spectral domain interferometry
摘要: This work evaluates the performance of the Complex Master Slave (CMS) method, that processes the spectra at the interferometer output of a spectral domain interferometry device without involving Fourier transforms (FT) after data acquisition. Reliability and performance of CMS are compared side by side with the conventional method based on FT, phase calibration with dispersion compensation (PCDC). We demonstrate that both methods provide similar results in terms of resolution and sensitivity drop-off. The mathematical operations required to produce CMS results are highly parallelizable, allowing real-time, simultaneous delivery of data from several points of different optical path differences in the interferometer, not possible via PCDC.
关键词: distance measurement,spectral domain interferometry,optical coherence tomography,dispersion compensation,phase calibration,Complex Master Slave,Fourier transforms
更新于2025-09-23 15:23:52
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Optical Coherence Tomography Angiography of Optic Disc and Macula Vessel Density in Glaucoma and Healthy Eyes
摘要: Aim: To study the microvascular density of the macular and optic nerve head in healthy and glaucoma subjects using optical coherence tomography angiography. Methodology: We performed a cross-sectional cohort study on healthy subjects and patients with glaucoma. The AngioVue Enhanced Microvascular Imaging System was used to capture the optic nerve head and macula images during one visit. En face segment images of the macular and optic disc were studied in layers. Microvascular density of the optic nerve head and macula were quanti?ed by the number of pixels measured by a novel in-house developed software. Areas under the receiver operating characteristic curves (AUROC) were used to determine the accuracy of differentiating between glaucoma and healthy subjects. Results: A total of 24 (32 eyes) glaucoma subjects (57.5 ± 9.5-y old) and 29 (58 eyes) age-matched controls (51.17 ± 13.5-y old) were recruited. Optic disc and macula scans were performed showing a greater mean vessel density (VD) in healthy compared with glaucoma subjects. The control group had higher VD than the glaucoma group at the en face segmented layers of the optic disc (optic nerve head: 0.209 ± 0.05 vs. 0.110 ± 0.048, P < 0.001; vitreoretinal interface: 0.086 ± 0.045 vs. 0.052 ± 0.034, P = 0.001; radial peripapillary capillary: 0.146 ± 0.040 vs. 0.053 ± 0.036, P < 0.001; and choroid: 0.228 ± 0.074 vs. 0.165 ± 0.062, P < 0.001). Similarly, the VD at the macula was also greater in controls than glaucoma patients (super?cial retina capillary plexus: 0.115 ± 0.016 vs. 0.088 ± 0.027, P < 0.001; deep retina capillary plexus: 0.233 ± 0.027 vs. 0.136 ± 0.073, P < 0.001; outer retinal capillary plexus: 0.190 ± 0.057 vs. 0.136 ± 0.105, P = 0.036; and choriocapillaris: 0.225 ± 0.053 vs. 0.153 ± 0.068, P < 0.001. The AUROC was highest for optic disc radial peripapillary capillary (0.96), followed by nerve head (0.92) and optic disc choroid (0.76). At the macula, the AUROC was highest for deep retina (0.86), followed by choroid (0.84), super?cial retina (0.81), and outer retina (0.72). Conclusions: Microvascular density of the optic disc and macula in glaucoma patients was reduced compared with healthy controls. VD of both optic disc and macula had a high diagnostic ability in differentiating healthy and glaucoma eyes.
关键词: optical coherence tomography angiography,glaucoma,microvascular density
更新于2025-09-23 15:23:52