Choroidal Thickness, Vascular Hyperpermeability, and Complement Factor H in Age-Related Macular Degeneration and Polypoidal Choroidal Vasculopathy
ABSTRACT To investigate the relationship between subfoveal choroidal thickness, choroidal vascular hyperpermeability, and complement factor H (CFH) gene polymorphism in typical age-related macular degeneration (AMD) and polypoidal choroidal vasculopathy (PCV).
Fifty-eight patients with typical AMD and 63 patients with PCV underwent fluorescein angiography, indocyanine green angiography (IA), and spectral-domain optical coherence tomography (OCT) using enhanced depth imaging (EDI). Subfoveal choroidal thickness was measured using EDI-OCT images, and choroidal hyperpermeability was evaluated using late-phase IA images. The major AMD-associated single-nucleotide polymorphisms were genotyped in 86 patients.
Mean subfoveal choroidal thickness was significantly lower in eyes with typical AMD than that in eyes with PCV (P = 0.025). Subfoveal choroidal thickness was greater in eyes with choroidal hyperpermeability than that in eyes without it in typical AMD (P < 0.001) and PCV (P = 0.020), and in the fellow eyes of typical AMD (P < 0.001) and PCV (P = 0.027). In eyes without choroidal hyperpermeability, the mean subfoveal choroidal thickness was greater in PCV than that in typical AMD (P = 0.001). Choroidal thickness decreased after photodynamic therapy combined with intravitreal ranibizumab in typical AMD (P = 0.016) and PCV (P = 0.036). In eyes with PCV, the I62V polymorphism in the CFH gene contributed to choroidal thickness (P = 0.043).
Choroidal thickness is related to the AMD subtypes, choroidal hyperpermeability, and I62V CFH gene polymorphism. In eyes without choroidal hyperpermeability, EDI-OCT is useful as an auxiliary measure for differentiating typical AMD and PCV.
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ABSTRACT: The choroid is a densely layer under the retinal pigment epithelium (RPE). Its deeper boundary is formed by the sclera, the outer fibrous shell of the eye. However, the inhomogeneity within the layers of choroidal Optical Coherence Tomography (OCT)-tomograms presents a significant challenge to existing segmentation algorithms. In this paper, we performed a statistical study of retinal OCT data to extract the choroid. This model fits a Gaussian mixture model (GMM) to image intensities with Expectation Maximization (EM) algorithm. The goodness of fit for proposed GMM model is computed using Chi-square measure and is obtained lower than 0.04 for our dataset. After fitting GMM model on OCT data, Bayesian classification method is employed for segmentation of the upper and lower border of boundary of retinal choroid. Our simulations show the signed and unsigned error of -1.44 +/- 0.5 and 1.6 +/- 0.53 for upper border, and -5.7 +/- 13.76 and 6.3 +/- 13.4 for lower border, respectively. © (2014) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.Proc. SPIE 9038, Medical Imaging 2014: Biomedical Applications in Molecular, Structural, and Functional Imaging, 90381K, San Diego; 02/2014
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ABSTRACT: PURPOSE: To investigate the relationship between the clinical characteristics of polypoidal choroidal vasculopathy (PCV) and choroidal vascular hyperpermeability seen on indocyanine green angiography. DESIGN: Retrospective, consecutive, interventional case series. METHODS: We reviewed the medical records and the angiograms of 89 patients with PCV. The relationship between choroidal vascular hyperpermeability and background factors, associated clinical manifestations, and treatment responses to intravitreal injections of ranibizumab were evaluated. RESULTS: Of the 89 patients with PCV, 31 patients (34.8%) demonstrated choroidal vascular hyperpermeability. The patients with choroidal vascular hyperpermeability more frequently showed bilateral neovascular membrane than those without choroidal vascular hyperpermeability (P=.009) and had a significant relationship with a history of central serous chorioretinopathy (CSC) (P=.01). Of the 98 eyes with treatment-naïve PCV, 34 eyes with choroidal vascular hyperpermeability demonstrated significantly greater subfoveal thickness than the 64 eyes without choroidal vascular hyperpermeability (P < .001). However, no significant relationship was found between choroidal vascular hyperpermeability and the other biomicroscopic and angiographic phenotypes of PCV. Three monthly intravitreal injections of ranibizumab were performed on 57 patients with treatment-naïve PCV, and the presence of choroidal vascular hyperpermeability was significantly related to the persistent retinal fluid 1 month after the third ranibizumab injection (P=.01). CONCLUSIONS: The patients with PCV associated with choroidal vascular hyperpermeability more frequently demonstrated bilateral neovascular membrane, a history of CSC, a thickened choroid, and poor responses to intravitreal injections of ranibizumab than those without choroidal vascular hyperpermeability.American Journal of Ophthalmology 09/2012; 155(2). DOI:10.1016/j.ajo.2012.07.018 · 4.02 Impact Factor
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ABSTRACT: Purpose: To develop and evaluate a fully automated three-dimensional method for segmentation of the choroidal vessels, quantification of choroidal vasculature thickness and choriocapillaris-equivalent thickness of the macula, and evaluate repeat variability in normal subjects using standard clinically available SD-OCT. Methods: normal subjects (24) were imaged twice, using clinically available, 3D spectral-domain optical coherence tomography (Cirrus, Carl-Zeiss, Dublin, CA). A novel, fully-automated three-dimensional method was used to segment and visualize the choroidal vasculature in macular scans. Local choroidal vasculature and choriocapillaris-equivalent thicknesses were determined. Reproducibility on repeat imaging was analyzed using overlapping rates, Dice coefficient, and Root Mean Square Coefficient of Variation (CV) of choroidal vasculature and choriocapillaris-equivalent thicknesses. Results: For the 6x6 mm2 macula-centered region as depicted by the SD-OCT , average choroidal vasculature thickness in normal subjects was 172.1µm (95% CI, 163.7-180.5µm) and average choriocapillaris-equivalent thickness was 23.1µm (95% CI, 20.0-26.2µm). Overlapping rates were 0.79 ± 0.07 and 0.75 ± 0.06, Dice coefficient was 0.78 ± 0.08, CV of choroidal vasculature thickness was 8.0% (95% CI, 6.3%-9.4%), and of choriocapillaris-equivalent thickness, 27.9% (95% CI, 21.0%-33.3%). Conclusion: Fully automated three-dimensional segmentation and quantitative analysis of the choroidal vasculature and choriocapillaris-equivalent thickness demonstrated excellent reproducibility in repeat scans (CV 8.0%) and good reproducibility of choriocapillaris-equivalent thickness (CV 27.9%). Our method has a potential to improve the diagnosis and management of patients with eye diseases in which the choroid is affected.Investigative ophthalmology & visual science 10/2012; 53(12). DOI:10.1167/iovs.12-10311 · 3.66 Impact Factor