scholarly journals Segmentation of Choroidal Boundary in Enhanced Depth Imaging OCTs Using a Multiresolution Texture Based Modeling in Graph Cuts

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Hajar Danesh ◽  
Raheleh Kafieh ◽  
Hossein Rabbani ◽  
Fedra Hajizadeh
Keyword(s):  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Automatic Segmentation ◽  
Gaussian Mixture ◽  
Graph Cut ◽  
Enhanced Depth Imaging ◽  
Cross Sectional ◽  
Depth Imaging ◽  
Cross Sectional Imaging

The introduction of enhanced depth imaging optical coherence tomography (EDI-OCT) has provided the advantage of in vivo cross-sectional imaging of the choroid, similar to the retina, with standard commercially available spectral domain (SD) OCT machines. A texture-based algorithm is introduced in this paper for fully automatic segmentation of choroidal images obtained from an EDI system of Heidelberg 3D OCT Spectralis. Dynamic programming is utilized to determine the location of the retinal pigment epithelium (RPE). Bruch’s membrane (BM) (the blood-retina barrier which separates the RPE cells of the retina from the choroid) can be segmented by searching for the pixels with the biggest gradient value below the RPE. Furthermore, a novel method is proposed to segment the choroid-sclera interface (CSI), which employs the wavelet based features to construct a Gaussian mixture model (GMM). The model is then used in a graph cut for segmentation of the choroidal boundary. The proposed algorithm is tested on 100 EDI OCTs and is compared with manual segmentation. The results showed an unsigned error of 2.48 ± 0.32 pixels for BM extraction and 9.79 ± 3.29 pixels for choroid detection. It implies significant improvement of the proposed method over other approaches likek-means and graph cut methods.

scholarly journals Optical Coherence Tomography Characteristics of the Choroid Underlying Congenital Hypertrophy of the Retinal Pigment Epithelium

2020 ◽  
Vol 6 (4) ◽  
pp. 238-243
Author(s):  
Jasmine H. Francis ◽  
Ethan K. Sobol ◽  
Molly Greenberg ◽  
Robert Folberg ◽  
David H. Abramson
Keyword(s):  
Optical Coherence Tomography ◽  
Retinal Pigment Epithelium ◽  
Choroidal Thickness ◽  
Retinal Thickness ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Enhanced Depth Imaging ◽  
Optical Coherence ◽  
Depth Imaging ◽  
Congenital Hypertrophy

Purpose: This study evaluates and characterizes the choroid underlying congenital hypertrophy of the retinal pigment epithelium (CHRPE). Methods: Retrospective observational study of CHRPE at least 2 mm in diameter. Choroidal vascular architecture was qualitatively examined. Choroidal thickness was measured by 2 independent observers using enhanced depth imaging spectral domain optical coherence tomography. Results: Forty-six eyes of 46 patients with CHRPE were included. Thirty-two lesions had imaging sufficient for analysis. Haller’s layer was healthy in 18 (56%), thin in 13 (41%), and absent in 1 (2%). Sattler’s layer was atrophic in 30 (94%), and choriocapillaris was atrophic in 31 (97%). CHRPE with thinned Haller’s layer had significantly larger diameter. The mean sub-CHRPE choroidal thickness was 82.4 ± 7.9 µm, compared to a thickness of 148.4 ± 9.6 µm in the normal adjacent choroid (p < 0.0001). Mean retinal thickness overlying the CHRPE was 77.3 ± 4.3 µm, compared to a retinal thickness of 137.8 ± 2.9 µm overlying the normal adjacent choroid (p < 0.0001). Sub-CHRPE choroidal thickness was a mean of 56.2 ± 3.1% of the adjacent normal choroidal thickness. Conclusion: The underlying choroid CHRPE is thinner than the adjacent normal choroid. All layers of the choroid can be thin with a preference of the inner Sattler’s and choriocapillaris layers.

scholarly journals MACULOPATHY AND CHORIORETINOPATHY IN CHILDREN WITH RETINOBLASTOMA RECEIVING CHEMOTHERAPY: CLINICAL TRIALS AND MORPHOMETRIC ANALYSIS

2018 ◽  
Vol 13 (4) ◽  
pp. 167-175
Author(s):  
S. V Saakyan ◽  
Elena В. Myakoshina ◽  
V. G Polyakov ◽  
T. L Ushakova ◽  
D. M Ismailova
Keyword(s):  
Optical Coherence Tomography ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Enhanced Depth Imaging ◽  
Optical Coherence ◽  
Depth Imaging ◽  
Chemotherapy Group ◽  
Intravitreal Chemotherapy ◽  
Group 3 ◽  
Group 2

Purpose. This research is to evaluate patients with retinoblastoma, who receive chemotherapy, with Spectralis optical coherence tomography with enhanced depth imaging to compare the signs of chorioretinopathy and maculopathy. Material and methods. 74 patients were examined and treated, 125 eyes with retinoblastoma in age at average of 24 ± 1.6 months. Group 1 - 31 patients, 62 eyes after intravenous chemotherapy, 2 - 24 patients, 25 eyes after intravenous and superselective intraarterial or intravitreal chemotherapy. Group 3 (control) - 19 patients (38 eyes) with primary retinoblastoma. The condition of the retina, choroid and macula was assessed using Ret Cam II and Spectralis optical coherence tomography with enhanced depth imaging. All patients had complete tumor resorption after treatment. Results. In group 1, after 3 courses of chemotherapy Spectralis optical coherence tomography with enhanced depth imaging showed a decrease of caliber of retinal vessels; wavelength of photoreceptors, hyperreflective round foci and calcinates in the retinal pigment epithelium; choriocapillary hyperreflexivity, choroid thinning; in the sclera - hyperreflective foci with visualization of the scleral vessels. In the macula - disorganization of retinal pigment epithelium, cystic edema, smoothness of the papillomacular bundle, coracoid form of the fovea, retinal thickening. After 3 courses of systemic chemotherapy and superselective intraarterial chemotherapy (group 2) - peritumoral increase in the caliber of retinal vessels. After systemic superselective intraarterial and intravitreal chemotherapy (group 2) - epiretinal membranes, punctate hyperreflective foci in the inner layers of the retina. In group 3 (control), before treatment, a normal anatomical and topographic state of the macula was observed with extracentral localization of retinoblastoma. Conclusions. Profound morphometric disturbances that come with combined chemotherapy (intravenous, superselective intraarterial and intravitreal chemotherapy treatments) call for a more careful treatment with methods selected in terms of Spectralis optical coherence tomography with enhanced depth imaging findings and specific chemotherapy contraindications.

scholarly journals Multimodal imaging in choroidal metastasis

2020 ◽  
Author(s):  
Gilda Cennamo ◽  
Daniela Montorio ◽  
Marianna Carosielli ◽  
Mario R. Romano ◽  
Giovanni Cennamo
Keyword(s):  
Multimodal Imaging ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Subretinal Fluid ◽  
Enhanced Depth Imaging ◽  
Choroidal Metastasis ◽  
Depth Imaging ◽  
Lipofuscin Pigment ◽  
Imaging Optical Coherence Tomography ◽  
Intraocular Tumours

Background: Choroidal metastasis represent the most common malignant intraocular tumours. Objectives: To detect the structural and vascular features of choroidal metastasis by multimodal imaging. Methods: Sixteen eyes of 16 patients with choroidal metastasis were enrolled in this prospective study. The multimodal imaging was performed in all patients: fluorescein angiography, indocyanine green angiography, enhanced depth imaging optical coherence tomography (EDI-OCT), OCT angiography (OCTA) and ultrasonography. Results: The choroidal metastasis were located in the macula region in 9 eyes (57%) and in the extramacular region in 7 eyes (43%). EDI-OCT showed a mean thickness of 950 ± 246 µm, a smooth anterior tumour surface in 5 eyes (31%) and a lumpy bumpy appearance in 11 eyes (69%). The most frequent EDI-OCT features were represented by choriocapillaris thinning (100%), shaggy photoreceptors (82%), subretinal fluid with speckles (69%), subretinal lipofuscin pigment (6%), absence of drusen (100%), optical shadowing (94%), low internal optical reflectivity (75%) and retinal pigment epithelium alterations (43%). OCTA revealed an absence of intratumoral vascular network in all cases.

scholarly journals Mid-Phase Hyperfluorescent Plaques Seen on Indocyanine Green Angiography in Patients with Central Serous Chorioretinopathy

2021 ◽  
Vol 10 (19) ◽  
pp. 4525
Author(s):  
Elodie Bousquet ◽  
Julien Provost ◽  
Marta Zola ◽  
Richard F. Spaide ◽  
Chadi Mehanna ◽  
...  
Keyword(s):  
Indocyanine Green ◽  
Central Serous Chorioretinopathy ◽  
Indocyanine Green Angiography ◽  
Pigment Epithelium ◽  
Fundus Autofluorescence ◽  
Retinal Pigment ◽  
Multiple Logistic Regression Analysis ◽  
Enhanced Depth Imaging ◽  
Depth Imaging ◽  
Chronic Form

(1) Indocyanine green angiography (ICG-A) shows the presence of mid-phase hyperfluorescent area in central serous chorioretinopathy (CSCR). However, their exact meaning remains uncertain. (2) The clinical and multimodal imaging findings of 100 patients (133 eyes) with CSCR, including the enhanced-depth-imaging OCT (EDI-OCT), blue-light fundus autofluorescence (BAF), fluorescein and indocyanine green angiography (FA and ICG-A) findings were reviewed. Mid-phase hyperfluorescent plaques (MPHP) were defined as fairly well circumscribed hyperfluorescent regions during the midphase of the ICG-A. The association between MPHP and other clinical/imaging parameters was assessed using a multiple logistic regression analysis. (3) MPHP were detected in 59.4% of eyes with CSCR. The chronic form of the disease, the presence of irregular pigment epithelium detachments (PED) and the retinal pigment epithelium (RPE) changes seen on FA were associated with the presence of MPHP in the multivariate analysis (p = 0.015; p = 0.018 and p = 0.002; respectively). OCT showed RPE bulges or PED in 98.7% of areas with MPHP and BAF showed changes in 57.3% of areas with MPHP. (4) MPHP were associated with a chronic form of CSCR and colocated with PED or RPE bulges. MPHP should be recognized as a sign of early RPE dysfunction before it is detected with BAF.

scholarly journals Ocular Toxoplasmosis: Mechanisms of Retinal Infection and Experimental Models

Parasitologia ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 50-60
Author(s):  
Veronica Rodriguez Fernandez ◽  
Giovanni Casini ◽  
Fabrizio Bruschi
Keyword(s):  
Ex Vivo ◽  
Cell Damage ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Treatment Strategies ◽  
Experimental Models ◽  
Ocular Toxoplasmosis ◽  
Cell Infection

Ocular toxoplasmosis (OT) is caused by the parasite Toxoplasma gondii and affects many individuals throughout the world. Infection may occur through congenital or acquired routes. The parasites enter the blood circulation and reach both the retina and the retinal pigment epithelium, where they may cause cell damage and cell death. Different routes of access are used by T. gondii to reach the retina through the retinal endothelium: by transmission inside leukocytes, as free parasites through a paracellular route, or after endothelial cell infection. A main feature of OT is the induction of an important inflammatory state, and the course of infection has been shown to be influenced by the host immunogenetics. On the other hand, there is evidence that the T. gondii phenotype also has an impact on the distribution of the pathology in different areas. Although considerable knowledge has been acquired on OT, a deeper knowledge of its mechanisms is necessary to provide new, more targeted treatment strategies. In particular, in addition to in vitro and in vivo experimental models, organotypic, ex vivo retinal explants may be useful in this direction.

scholarly journals OCT imaging of rod mitochondrial respiration in vivo

2021 ◽  
pp. 153537022110137
Author(s):  
Bruce A Berkowitz ◽  
Haohua Qian
Keyword(s):  
Signaling Pathway ◽  
Mitochondrial Respiration ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
The Body ◽  
Subretinal Space ◽  
Outer Retina ◽  
Water Efflux ◽  
Resolution Imaging

There remains a need for high spatial resolution imaging indices of mitochondrial respiration in the outer retina that probe normal physiology and measure pathogenic and reversible conditions underlying loss of vision. Mitochondria are involved in a critical, but somewhat underappreciated, support system that maintains the health of the outer retina involving stimulus-evoked changes in subretinal space hydration. The subretinal space hydration light–dark response is important because it controls the distribution of vision-critical interphotoreceptor matrix components, including anti-oxidants, pro-survival factors, ions, and metabolites. The underlying signaling pathway controlling subretinal space water management has been worked out over the past 30 years and involves cGMP/mitochondria respiration/pH/RPE water efflux. This signaling pathway has also been shown to be modified by disease-generating conditions, such as hypoxia or oxidative stress. Here, we review recent advances in MRI and commercially available OCT technologies that can measure stimulus-evoked changes in subretinal space water content based on changes in the external limiting membrane-retinal pigment epithelium region. Each step within the above signaling pathway can also be interrogated with FDA-approved pharmaceuticals. A highlight of these studies is the demonstration of first-in-kind in vivo imaging of mitochondria respiration of any cell in the body. Future examinations of subretinal space hydration are expected to be useful for diagnosing threats to sight in aging and disease, and improving the success rate when translating treatments from bench-to-bedside.

The cytoskeletal elements of human retinal pigment epithelium: in vitro and in vivo

1988 ◽  
Vol 91 (2) ◽  
pp. 303-312
Author(s):  
N.M. McKechnie ◽  
M. Boulton ◽  
H.L. Robey ◽  
F.J. Savage ◽  
I. Grierson
Keyword(s):  
Retinal Pigment Epithelium ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Cytokeratin 18 ◽  
Rpe Cells ◽  
Human Retinal Pigment Epithelium ◽  
Cytoskeletal Elements

The cytoskeletal elements of normal (in situ) and cultured human retinal pigment epithelium (RPE) were studied by a variety of immunocytochemical techniques. Primary antibodies to vimentin and cytokeratins were used. Positive immunoreactivity for vimentin was obtained with in situ and cultured material. The pattern of reactivity obtained with antisera and monoclonals to cytokeratins was more complex. Cytokeratin immunoreactivity could be demonstrated in situ and in cultured cells. The pattern of cytokeratin expression was similar to that of simple or glandular epithelia. A monoclonal antibody that specifically recognizes cytokeratin 18 identified a population of cultured RPE cells that had particularly well-defined filamentous networks within their cytoplasm. Freshly isolated RPE was cytokeratin 18 negative by immunofluorescence, but upon culture cytokeratin 18 positive cells were identifiable. Cytokeratin 18 positive cells were identified in all RPE cultures (other than early primaries), regardless of passage number, age or sex of the donor. In post-confluent cultures cytokeratin 18 cells were identified growing over cytokeratin 18 negative cells, suggesting an association of cytokeratin 18 immunoreactivity with cell proliferation. Immunofluorescence studies of retinal scar tissue from two individuals revealed the presence of numerous cytokeratin 18 positive cells. These findings indicate that RPE cells can be identified by their cytokeratin immunoreactivity and that the overt expression of cytokeratin 18 may be associated with proliferation of human RPE both in vitro and in vivo.

scholarly journals In vivo analysis of glaucoma-related features within the optic nerve head using enhanced depth imaging optical coherence tomography

PLoS ONE ◽  
2017 ◽  
Vol 12 (7) ◽  
pp. e0180128 ◽  
Author(s):  
Tiago S. Prata ◽  
Flavio S. Lopes ◽  
Vitor G. Prado ◽  
Izabela Almeida ◽  
Igor Matsubara ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Optic Nerve ◽  
Optic Nerve Head ◽  
Enhanced Depth Imaging ◽  
Optical Coherence ◽  
Depth Imaging ◽  
In Vivo Analysis ◽  
Imaging Optical Coherence Tomography

JAM-C maintains VEGR2 expression to promote retinal pigment epithelium cell survival under oxidative stress

2017 ◽  
Vol 117 (04) ◽  
pp. 750-757
Author(s):  
Xin Jia ◽  
Chen Zhao ◽  
Qishan Chen ◽  
Yuxiang Du ◽  
Lijuan Huang ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Retinal Pigment Epithelium ◽  
Cell Survival ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Retinal Pigment Epithelium Cell ◽  
Photoreceptor Cells ◽  
Rpe Cells

SummaryJunctional adhesion molecule-C (JAM-C) has been shown to play critical roles during development and in immune responses. However, its role in adult eyes under oxidative stress remains poorly understood. Here, we report that JAM-C is abundantly expressed in adult mouse retinae and choroids in vivo and in cultured retinal pigment epithelium (RPE) and photoreceptor cells in vitro. Importantly, both JAM-C expression and its membrane localisation are downregulated by H2O2-induced oxidative stress. Under H2O2-induced oxidative stress, JAM-C is critically required for the survival of human RPE cells. Indeed, loss of JAM-C by siRNA knockdown decreased RPE cell survival. Mechanistically, we show that JAM-C is required to maintain VEGFR2 expression in RPE cells, and VEGFR2 plays an important role in keeping the RPE cells viable since overexpression of VEGFR2 partially restored impaired RPE survival caused by JAM-C knockdown and increased RPE survival. We further show that JAM-C regulates VEGFR2 expression and, in turn, modulates p38 phosphorylation. Together, our data demonstrate that JAM-C plays an important role in maintaining VEGR2 expression to promote RPE cell survival under oxidative stress. Given the vital importance of RPE in the eye, approaches that can modulate JAM-C expression may have therapeutic values in treating diseases with impaired RPE survival.

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