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oe1(光电查) - 科学论文

17 条数据
?? 中文(中国)
  • Retinal vascular density evaluated by optical coherence tomography angiography in macular telangiectasia type 2

    摘要: Purpose To evaluate the retinal and choroidal vascular changes through optical coherence tomography angiography (OCTA) in patients with macular telangiectasia type 2 (MacTel 2). Methods Our study included 20 patients (40 eyes) with MacTel 2, and age-matched and sex-matched 18 subjects (36 eyes) in the control group. Fundus color photographs, fundus autofluorescence, fundus fluorescein angiography, spectral-domain optical coherence tomography and OCTA were performed. Foveal vascular density and parafoveal vascular density (PFVD), and foveal retinal thickness and parafoveal retinal thickness, choroidal thickness (CT) and retinal ganglion cell–inner plexiform layer (GCIPL) were compared between MacTel 2 patients and normal age-matched controls. Results The retinal whole vascular density and PFVD of the deep plexus were significantly lower in patients with MacTel 2 than that of the control group (56.93% vs. 58.54%, p = 0.003; and 60.38% vs. 61.66%, p = 0.045). The foveal avascular zone (FAZ) of the deep plexus was significantly enlarged in patients with MacTel 2 than that of the control group (0.44 vs. 0.36, p = 0.009). There was a positive and statistically significant correlation between the FAZ of the superficial and deep plexus and CT in patients with MacTel 2. There was a positive and statistically significant correlation between retinal whole, parafoveal temporal quadrant vascular density of the superficial and deep plexus and GCIPL thickness in patients with MacTel 2. Conclusions Our study demonstrated that important retinal vascular density and FAZ changes in MacTel 2 occur in the deep capillary plexus of the retina.

    关键词: Macular telangiectasia type 2,Vascular density,Choroidal thickness,Retinal ganglion cell–inner plexiform layer,Optical coherence tomography angiography

    更新于2025-09-23 15:23:52

  • Choroidal thickness in healthy eyes using enhanced depth imaging optical coherence tomography and comparison with cases of retinitis pigmentosa

    摘要: Introduction. — The goal of this study was to measure by spectral domain optical coherence tomography (SD-OCT) with EDI the choroidal thickness in healthy subjects and to compare these parameters with those of patients with retinitis pigmentosa (RP). Methods. — Data were obtained from 60 healthy patients without history or family history of retinal or choroidal disease or glaucoma. A case-control study was also conducted on 40 eyes of 20 patients with RP and 40 eyes of 20 healthy refraction- and age-matched controls, selected from among the 60 healthy patients. OCT was used with the EDI protocol. The primary outcome measure was choroidal thickness. Results. — Among healthy patients, the overall choroidal thickness was 287.7 μm. Mean choroidal thickness was lower on the nasal side (236.6 μm from the fovea) compared with the temporal side (262.3 μm, P = 0.002). It also varied according to age, being highest among 20—29-year-old patients and decreasing thereafter with increasing age. Choroidal thickness was significantly higher in healthy patients than in RP patients, regardless of the location (P < 0.001). Conclusion. — This observational study confirms that choroidal thickness varies with age and location. It decreases in subjects with RP and is related to worsening of retinal damage, independently of age-related thinning. Further studies are needed to understand whether choroidal vascular alteration is a cause or a consequence of the degenerative pathology.

    关键词: Photoreceptor degeneration,Choroidal thickness,Case-control study,Retinitis pigmentosa,Enhanced depth imaging optical coherence tomography

    更新于2025-09-23 15:23:52

  • Swept source optical coherence tomography analysis of choroidal thickness in macular telangiectasia type 2: a case-control study

    摘要: Purpose There has been a recent interest in the association of macular telangiectasia (MacTel) type 2 with central serous choroidopathy and other pachychoroid disorders. This study was performed to assess the subfoveal choroidal thickness (SFCT) in patients with MacTel type 2 and compare it with healthy controls using swept source optical coherence tomography (SS-OCT). Methods It was a retrospective case-control study performed at a tertiary eye care center. The cases constituted patients with MacTel type 2 detected over the last 2 years (April 2016 to March 2018). The controls were healthy adults with no posterior segment pathology. The patients were evaluated with color fundus photography, SS-OCT (Triton, Topcon Inc., Oakland, New Jersey, USA) and fundus fluorescein angiography. The cases were staged based on Gass and Blodi classification. SFCT was compared between the two groups. Results Sixty-five eyes of 33 patients with MacTel were included. The controls consisted of 61 eyes of 33 healthy age-matched (p = 0.81) and sex-matched (p = 0.31) adults. The mean SFCT in cases (353.0 ± 91.2 μm) was higher than controls (289.2 ± 69.0 μm), and this difference was statistically significant (p = 0.0001). The mean SFCT was different in various stages: 346.6 ± 86.3 μm (stage 2), 334.6 ± 90.2 μm (stage 3), 374.6 ± 94.0 μm (stage 4), and 294.8 ± 68.8 μm (stage 5), though this was not statistically significant (p = 0.28). Conclusions The choroid in MacTel type 2 patients was significantly thickened as compared to controls. SFCT may vary as the structural changes worsen over time.

    关键词: Macular telangiectasia type 2,Swept source optical coherence tomography,Subfoveal choroidal thickness,Enhanced depth imaging

    更新于2025-09-23 15:22:29

  • Evaluation of choroidal and retinal thickness measurements in adult hemodialysis patients using spectral-domain optical coherence tomography

    摘要: Purpose: To assess the effect of hemodialysis on retinal and choroidal thicknesses using spectral-domain optical coherence tomography (SD-OCT). Methods: In this prospective interventional study, 25 hemodialysis patients (17 male, 8 female) were enrolled. All participants underwent high-speed, high-resolution SD-OCT (λ=840 mm; 26.000 A-scans/s; 5 μm resolution) before and after hemodialysis. Choroidal thickness was measured perpendicularly from the outer edge of the retinal pigment epithelium to the choroid-sclera boundary at the fovea and at five additional points: 500 μm and 1000 μm nasal to the fovea and 500 μm, 1000 μm, and 1500 μm temporal to the fovea. Two masked physicians performed the measurements. Choroidal and retinal thicknesses before and after hemodialysis were compared. results: The median choroidal thicknesses before and after hemodialysis were 182 μm (range, 103-374 μm) and 161 μm (range, 90-353 μm), respectively (P<0.001). The median retinal thicknesses were 246 μm (range, 179-296 μm) before and 248 μm (range, 141-299 μm) after hemodialysis (P>0.05). Systolic arterial pressure, diastolic arterial pressure, mean arterial pressure, heart rate, and ocular perfusion pressure significantly decreased after hemodialysis (P<0.001). Intraocular pressure did not vary significantly (P=0.540). conclusion: Hemodialysis seems to cause a significant decrease in choroidal thickness, whereas it has no effect on retinal thickness. This significant decrease in choroidal thickness might be due to the extensive fluid absorption in hemodialysis, which could result in decreased ocular blood flow.

    关键词: Choroidal thickness,Hemodialysis,Optical coherence tomography

    更新于2025-09-23 15:22:29

  • Choroidal imaging biomarkers

    摘要: The choroid is the vascular coat of the eye,and its role has been studied in multiple chorioretinal disorders. The recent advancements in choroidal imaging techniques including enhanced depth imaging optical coherence tomography (EDI-OCT), swept source (SS-OCT), enface OCT and OCT angiography have facilitated an in-depth analysis of choroid. The gradual shift from manual to automated segmentation and binarization methods have led to precise and reproducible measurements of choroidal parameters. These qualitative and quantitative parameters, called choroidal imaging biomarkers, have evolved over the past decade from a simple linear subfoveal choroidal thickness to more complex 3 dimensional (3-D) choroidal reconstruction thus widening the spectrum encompassing multiple parameters. These biomarkers have provided a better understanding of the pathogenesis, are helpful in diagnostic dilemmas, and in future may also help to devise treatment options. The lack of normative data, absence of standardized parameters and limitations of the imaging techniques, however, have led to ambiguity and difficulty in the interpretation of these variables. We attempt to address these lacunae in the literature and provide a basic understanding of the choroid in both health and disease using these choroidal biomarkers.

    关键词: Optical coherence tomography angiography (OCTA),En-face OCT,Swept source optical coherence tomography (SS-OCT),Choroidal thickness,Choroidal vascularity index (CVI),Choroidal imaging biomarkers,Choroidal volume

    更新于2025-09-23 15:21:21

  • Relationship between the Lamina Cribrosa, Outer Retina, and Choroidal Thickness as Assessed Using Spectral Domain Optical Coherence Tomography

    摘要: To evaluate the characteristics and relationship between peripapillary choroidal thickness (pCT), lamina cribrosa thickness (LCT), and peripapillary outer retinal layer thickness (pORT) as determined using spectral domain optical coherence tomography (SD-OCT) enhanced depth imaging (EDI).

    关键词: Outer retinal thickness,Lamina cribrosa thickness,Optical coherence tomography,Choroidal thickness,Glaucoma

    更新于2025-09-23 15:21:01

  • Choroidal structure in subtypes of polypoidal choroidal vasculopathy determined by binarization of optical coherence tomographic images

    摘要: Importance: Chorodial structure in subtypes of polypoidal choroidal vasculopathy. Background: To evaluate choroidal vascularity in the eyes of patients with polypoidal choroidal vasculopathy (PCV) with and without choroidal vascular hyperpermeability (CVH). Design: A hospital-based retrospective study. Participants: Fifty-eight PCV patients (28 with CVH; 30 without CVH) and 30 normal controls were included in this study. Methods: All study subjects underwent spectral-domain optical coherence tomography with enhanced depth imaging, and the choroidal images were binarized into the luminal area and stromal area. Main outcome measures: Choroidal vascularity index (CVI) and subfoveal choroidal thickness (SFCT). Results: Compared to normal controls, patients with PCV showed no obvious difference in SFCT (p = 0.510), but significantly lower CVI (p = 0.003). Among PCV patients, the CVI in eyes with CVH was significantly greater than that in those without CVH (65.78 ± 4.70 vs. 62.28 ± 3.90; p = 0.002), and a significant difference in SFCT was also found between the two subtypes of PCV (340.8 ± 89.2 vs. 250.4 ± 67.7; p < 0.001). Conclusions and Relevance: PCV eyes with CVH have a greater CVI and a thicker SFCT than those without CVH. The significant differences in choroidal vascularity between the two subtypes of PCV may broaden our understanding of the pathogenesis of this disease and contribute to significant improvements in treatment.

    关键词: polypoidal choroidal vasculopathy,choroidal thickness,optical coherence tomography,choroidal vascular hyperpermeability,Choroidal vascularity index

    更新于2025-09-19 17:15:36

  • Comparison of optic coherence tomography results in patients with diagnosed epilepsy: Findings in favor of neurodegeneration

    摘要: Background: Epilepsy is a chronic neurological disease characterized with recurrent seizures. Progressive neuronal degeneration is a common consequence of long-term and/or recurrent seizure activity in epilepsy. Optical coherence tomography (OCT) is a new medical imaging technique that displays biological tissue layers as high-resolution tomographic sections. The aim of our study was to evaluate OCT findings in patients with epilepsy and to compare OCT findings in terms of disease duration, presence of status, seizure frequency, and drug use. Methods: Forty-three patients who had epilepsy according to the Commission on Classification and Terminology of the International League Against Epilepsy (ILAE) in 2010 and 40 healthy controls were recruited for the study. Disease duration, seizure frequency, status history, and multiple drug use were noted. Retinal nerve fiber layer (RNFL), ganglion cell layer (GCL), inner-plexiform layer (IPL), and choroid thinning were analyzed by using spectral OCT. Results: The mean RNFL values are 101.48 ± 11.33 in the patient group and 108.76 ± 8.37 in the control group (p = 0.001). The mean GCL thickness values in the patient and control groups are 1.14 ± 0.12 and 1.22 ± 0.05, (p < 0.001). The mean IPL thickness is 0.93 ± 0.09 in the patient group and 0.97 ± 0.05 in the control group (p = 0.02). Choroid thickness is significantly increased in the patient group (p < 0.001). Conclusions: Demonstration of RNFL, IPL, and GCL thinning might indicate neurodegeneration, and choroid thickening indicates neuroinflammation. We found no association between disease duration, seizure frequency, status history, and multiple drug use and OCT parameters. Further studies with larger patient groups should clarify the matter.

    关键词: Retinal nerve fiber layer,Optic coherence tomography,Choroidal thickness,Ganglion cell layer,Epilepsy

    更新于2025-09-19 17:15:36

  • Optical coherence tomography angiography analysis of changes in the retina and the choroid after haemodialysis

    摘要: The purpose of this study is to evaluate the effect of haemodialysis on perfused vessel density, choroidal thickness (CT), and retinal thickness in end-stage renal disease (ESRD) using swept-source optical coherence tomography angiography (SS-OCTA). We studied twenty-nine eyes of 29 ESRD patients by ophthalmologic examination and SS-OCTA before and after haemodialysis. The colour-coded perfusion density maps were generated and perfused vessel density was calculated. Changes in systemic and other ocular parameters such as retinal and choroidal thickness were measured and analysed. Total perfused vessel density decreased significantly after haemodialysis in the choriocapillaris; it was not significantly different in the superficial capillary plexus (SCP) and the deep capillary plexus (DCP). Total CT decreased significantly, but total retinal thickness was not significantly different. There was no significant correlation between choriocapillaris perfused vessel density and CT. The reduction in choriocapillaris perfused vessel density correlated with the decrease in systolic and mean arterial blood pressures. The decrease in CT correlated with the ultrafiltration volume. There were no significant systemic and ocular factors affecting change in retinal thickness and perfused vessel density of SCP and DCP. This is the first study to assess the effect of haemodialysis on blood flow changes using SS-OCTA; changes may be more prominent in the choroidal compared to the retinal layer.

    关键词: angiography,choroidal thickness,haemodialysis,Optical coherence tomography,end-stage renal disease,perfused vessel density,retinal thickness

    更新于2025-09-10 09:29:36

  • The effect of the optical design of multifocal contact lenses on choroidal thickness

    摘要: Studies have found reduced myopia progression with multifocal contact lenses, albeit with an unclear mechanism behind their protective effect. It is hypothesized that the induced myopic defocus of the addition zones of the multifocal contact lenses leads to choroidal thickening and therefore inhibits eye growth. In the current study, the effect of the optical design of multifocal contact lenses on choroidal thickness was investigated. Eighteen myopic participants wore four different contact lenses ((1) single-vision lenses corrected for distance, (2) single-vision lenses with +2.50 D full-field defocus, (3) Multifocal center-distance design, (4) Multifocal center-near design, both with addition power +2.50 D) for 30 min each on their right eye. Automated analysis of the macular choroidal thickness and vitreous chamber depth were performed before and after the wear of each of the contact lenses. Peripheral refraction profiles in primary gaze were obtained using eccentric photorefraction prior to contact lens wear. Choroidal thickness and vitreous chamber depth showed no significant differences to baseline with any of the contact lenses (all p > 0.05). Choroidal thickness increased by +2.1 ± 11.1 μm with the Multifocal center-distance design, by +2.0 ± 11.1 μm with the full-field defocus lens, followed by the Multifocal center-near design with +1.6 ± 11.3 μm and the single-vision contact lens correcting for distance with +0.9 ± 11.2 μm. Multifocal contact lenses have no significant influence on choroidal thickness after short-term wear. Therefore, changes in choroidal thickness might not be the main contributor to the protective effect of multifocal contact lenses in myopia control.

    关键词: multifocal contact lenses,choroidal thickness,optical design,defocus,myopia control

    更新于2025-09-10 09:29:36