Search results for "fundus oculi"
showing 10 items of 27 documents
A Fast Multiresolution Approach Useful for Retinal Image Segmentation
2018
Retinal diseases such as retinopathy of prematurity (ROP), diabetic and hypertensive retinopathy present several deformities of fundus oculi which can be analyzed both during screening and monitoring such as the increase of tortuosity, lesions of tissues, exudates and hemorrhages. In particular, one of the first morphological changes of vessel structures is the increase of tortuosity. The aim of this work is the enhancement and the detection of the principal characteristics in retinal image by exploiting a non-supervised and automated methodology. With respect to the well-known image analysis through Gabor or Gaussian filters, our approach uses a filter bank that resembles the “à trous” wav…
Effects of Study Population, Labeling and Training on Glaucoma Detection Using Deep Learning Algorithms
2020
Author(s): Christopher, Mark; Nakahara, Kenichi; Bowd, Christopher; Proudfoot, James A; Belghith, Akram; Goldbaum, Michael H; Rezapour, Jasmin; Weinreb, Robert N; Fazio, Massimo A; Girkin, Christopher A; Liebmann, Jeffrey M; De Moraes, Gustavo; Murata, Hiroshi; Tokumo, Kana; Shibata, Naoto; Fujino, Yuri; Matsuura, Masato; Kiuchi, Yoshiaki; Tanito, Masaki; Asaoka, Ryo; Zangwill, Linda M | Abstract: PurposeTo compare performance of independently developed deep learning algorithms for detecting glaucoma from fundus photographs and to evaluate strategies for incorporating new data into models.MethodsTwo fundus photograph datasets from the Diagnostic Innovations in Glaucoma Study/African Descent…
Peripapillary fluorescence lifetime reveals age-dependent changes using fluorescence lifetime imaging ophthalmoscopy in rats
2017
Abstract Many fundus diseases accompany fundus autofluorescence change. Fluorescence lifetime imaging ophthalmoscope (FLIO) is a latest technique in imaging fundus autofluorescence. With FLIO, the fundus fluorescence lifetime (FLT) is recorded topographically, assisting to diagnose and monitor multiple fundus diseases. The purpose of this study was to evaluate the repeatability of FLT using FLIO on adult rats and to analyze the age-dependency of the peripapillary FLT of the fundus in a short spectral channel (498–560 nm) and a long spectral channel (560–720 nm). Sprague Dawley rats (n of eyes = 10) were used for repeatability experiments. Age-dependent changes were investigated in young (tw…
Confocal scanning laser ophthalmoscopy versus modified conventional fundus camera for fundus autofluorescence.
2016
Fundus autofluorescence (FAF) is a noninvasive imaging method to detect fundus endogenous fluorophores, mainly lipofuscin located in the retinal pigment epithelium (RPE). The FAF provides information about lipofuscin distribution and RPE health, and consequently an increased accumulation of lipofuscin has been correlated with ageing and development of certain retinal conditions. Areas covered: An exhaustive literature search in MEDLINE (via OVID) and PUBMED for articles related to ocular FAF in retinal diseases and different devices used for acquiring FAF imaging was conducted. Expert commentary: This review aims to show an overview about autofluorescence in the RPE and the main devices use…
Multifocal choroiditis: Indocyanine green angiographic features
2001
The aim of this study is to retrospectively evaluate the indocyanine green (ICG) angiographic features in 13 patients affected by multifocal choroiditis. We identified two clinical and angiographic patterns. The ‘active’ pattern showed hypofluorescence up to the late phases and more extensive choroidal involvement than presumed by ophthalmoscopy and fluorescein angiography. In the ‘inactive’ pattern, ICG angiography showed hypofluorescence during all the phases: no increase in lesion number was observed between early and late phases. Choroidal neovascularization was present in 10 patients, and it was bilateral in 2 of these: it occurred only in the inactive stage. The appearance of choroida…
Effects of Early Postfiltration Ocular Hypotony on Visual Acuity, Long-term Intraocular Pressure Control, and Posterior Segment Morphology
2001
Purpose To determine whether hypotony after filtration surgery has any influence on visual acuity and intraocular pressure (IOP) lowering. Patients and methods We prospectively investigated 43 eyes of 43 patients undergoing trabeculectomy without the use of antimetabolites for 12 months. Results The lowest postoperative IOP valued 4.9 +/- 3.6 mm Hg (range, 0-14 mm Hg). It correlated statistically significant with the IOP 6 weeks (P = 0.016), 6 months (P = 0.009), and 1 year after surgery (P = 0.027). Eyes with a deterioration of visual acuity 6 weeks after surgery had undergone a stronger postoperative hypotony (correlation with lowest postoperative IOP, P = 0.035). The mean period with an …
Are signs of ocular tilt reaction in patients with cerebellar lesions mediated by the dentate nucleus?
2008
A sensitive clinical sign of a vestibular tone imbalance in the roll plane is the ocular tilt reaction (OTR), a combination of skew deviation, ocular torsion and head and perceptual tilts such as tilts of the subjective visual vertical (SVV). Of these OTR components tilts of SVV are the most frequent. While these signs are regularly seen in patients with unilateral brainstem lesions, only a few case studies are available on their occurrence in patients with cerebellar lesions. Thus, the question arises whether cerebellar structures may be involved in contra- and/or ipsiversive tilts of the perceived vertical and other signs of OTR. We used lesion-mapping techniques in a total of 31 patients…
Relationships between 24 h blood pressure load and target organ damage in patients with mild-to-moderate essential hypertension.
2001
Objective: To analyse the relationships between 24 h blood pressure load (the percentage of systolic/diastolic blood pressures exceeding 140/90 mmHg while awake and 120/80 mmHg during sleep) and some indices of hypertensive target organ involvement, independently of the mean level of 24 h blood pressure. Methods: One hundred and thirty patients with mild-to-moderate hypertension underwent 24 h ambulatory blood pressure monitoring, ocular fundus examination, microalbuminuria assay and two-dimensional guided M-mode echocardiography. The study population was divided into subsets according to the systolic and diastolic 24 h blood pressure load values predicted from the regression equation relat…
Visualization of corneal vascularization in peripheral hypertrophic subepithelial corneal opacification with OCT angiography.
2018
Purpose The major goal of this study was to test the hypothesis that in patients with peripheral hypertrophic subepithelial corneal opacification (PHSCO), visualization of corneal vessels is better with optical coherence tomography angiography (OCTA) than with conventional slit lamp microphotography. Methods Patients with PHSCO were included in this prospective study. The corneal findings were photographed using a slit lamp camera (Haag Streit BM 900® ) and visualized with anterior-segment OCT (Optovue XR Avanti, Fremont, California, USA). Additionally, OCTA with the Angiovue Imaging™ System was performed in the area of PHSCO. Results Thirty-four eyes of 19 patients (26% male and 74% female…
Optical coherence tomography of chorioretinal and choroidal folds
2007
. Purpose: To report the optical coherence tomography (OCT) findings in cases of chorioretinal and choroidal folds. Methods: Eight subjects with folds of the fundus of the eye were examined with fundus photography, fluorescein angiography, B-scan ultrasonography and Stratus OCT. Results: Two types patterns were found on OCT. Five cases showed undulating retinal as well as retinal pigment epithelial lines of normal thickness; these were defined as chorioretinal folds. The posterior vitreous surface often adhered to the crests of the folds only. Three cases exhibited a wavy appearance of the retinal pigment epithelium and a flat retinal surface; these were classified as choroidal folds. Co…