Search results for "Retinal"
showing 10 items of 631 documents
CORRELATION OF OPTICAL COHERENCE TOMOGRAPHY PATTERN AND VISUAL RECOVERY AFTER VITRECTOMY WITH SILICONE OIL FOR RETINAL DETACHMENT
2006
PURPOSE: To assess prospectively the features of the macular surface in silicone oil-filled eyes after surgery by analyzing whether silicone oil affects optical coherence tomography (OCT) measurements and their reproducibility and whether a statistical correlation exists between postoperative best-corrected visual acuity (BCVA) and foveal thickness measured by OCT. METHODS: Twenty eyes of 20 patients underwent vitrectomy with silicone oil tamponade for retinal detachment. After vitrectomy, complete ophthalmic examination including determination of BCVA and OCT was performed to quantify the visual recovery and the foveal thickness. RESULTS: Ophthalmoscopy revealed that the retina appeared to…
Association of Birth Weight With Foveolar Thickness in Adulthood: Results From a Population-Based Study
2021
Purpose Low birth weight (BW) is associated with alterations of foveal shape development in childhood—leading to an increased retinal thickness of the fovea. The aim of the present study was to assess whether BW has a long-term effect on foveal retinal thickness (RT) and is still present in adulthood. Methods In the German population-based Gutenberg Health Study (GHS), participants were examined with spectral-domain optical coherence tomography. The association between self-reported BW and RT in the foveolar and perifoveal locations was assessed. Multivariable linear regression analyses with adjustment for potential confounders and grading of foveal hypoplasia were performed. Results Overal…
Color and lightness constancy in different perceptual tasks
1998
Color and lightness constancy with respect to changing illumination was studied with three different perceptual tasks: ranking of colored papers according (1) to their lightness and (2) to their chromatic similarity in photopic, mesopic, and scotopic states of adaptation, and (3) recognition of remembered colored papers after changes of illumination in photopic vision. Constancy was found in the second task, only. Excitations of light receptors and luminance channels were computed to simulate the empirical rank orders. Results of the first task can be predicted with the hypothesis that luminance channels are activated, if lightness is asked for. Sequences arranged with respect to chromatic …
Optical coherence tomography of macular thickness after biaxial vs coaxial microincision clear corneal cataract surgery
2009
PURPOSE To evaluate macular thickness changes after biaxial microincision versus coaxial small incision cataract surgery using optical coherence tomography (OCT). METHODS This prospective, randomized, marked study comprised 70 patients (70 eyes) undergoing biaxial microincision surgery or conventional coaxial phacoemulsification. Patients were evaluated by Stratus OCT preoperatively and 1 day, 4 weeks, and 8 weeks postoperatively. Best-corrected visual acuity (BCVA), phacoemulsification power, and effective phacoemulsification time (EPT) were evaluated. RESULTS In the biaxial group, median foveal thickness changed from 160 microm preoperatively to 168 microm 8 weeks postoperatively (p=0.018…
Image quality and visual performance in the peripheral visual field following photorefractive keratectomy.
2002
ABSTRACT PURPOSE: A theoretical and experimental study was performed to assess the possible effects of photorefractive keratectomy (PRK) on retinal image quality and thresholds in the peripheral visual field. METHODS: Simple optical calculations suggest that although the quality of the retinal image at the fovea of the postoperative PRK eye may be comparable to that in an emmetropic eye, images in the peripheral field may be markedly worse, since peripheral ray bundles may pass partly through ablated and partly through unablated cornea, giving a simultaneous-vision bifocal effect. This would be expected to create an annular zone of confusion, so that light from two different directions in o…
Clinical patterns and electrophysiological findings in retinal pigment epithelium diseases. Does a correlation exist?
1986
At present it is difficult to distinguish those human chorioretinal diseases in which the retinal pigment epithelium (RPE) is the primary site of dysfunction. This difficulty is caused by several factors such as scarcity of biochemical and histological information and a lack of correlation of basic science information available with the clinical body of knowledge. In the present study we examined 134 eyes at early or late stages of hereditary diseases involving the RPE. We tried to distinguish primary RPE involvement by using standard ERG (a- and b-wave) and EOG testing. We conclude that in general primary RPE damage can be better assessed by current electrophysiology in those diseases whic…
Differentiation in medulloblastomas: correlation between the immunocytochemical demonstration of photoreceptor markers (S-antigen, rod-opsin) and the…
1989
Biopsy specimens of 66 medulloblastomas were investigated by means of S-antigen and rod-opsin immunocytochemistry. The patients were operated between 1969 and 1988 and the medical records were retrospectively evaluated to correlate the immunocytochemical features of the tumors to the course of the disease. S-antigen- and rod-opsin-immunoreactive tumor cells were found in 19 out of 66 cases. Since in the normal non-neoplastic state immunoreactive S-antigen and rod-opsin are restricted to retinal photoreceptors and a class of pinealocytes derived from photoreceptor cells, the occurrence of these proteins in certain tumor cells of medulloblastomas suggests a differentiation of these cells alon…
Experimental Percutaneous Cannulation of the Supraorbital Arteries: Implication for Future Therapy
2005
Purpose There is some evidence to suggest that thrombolysis has a beneficial effect in retinal vessel occlusion. However, there is concern that this therapeutic approach carries the risk of hemorrhage. Retrograde cannulation of the supraorbital arteries followed by irrigation with fibrinolytic agents may have the potential to minimize the risk of major complications. The study was conducted to investigate the anatomic and sonographic features of the supraorbital arteries. Methods This cadaver dissection study was performed on the orbits of 12 cadaveric specimens. In each orbit, the supraorbital region was dissected, followed by cannulation of the supraorbital vessels and injection of ink. I…
Long-term results of surgical treatment of high myopia with Worst-Fechner intraocular lenses
1995
Abstract This retrospective study evaluated the results in 90 eyes that had a minus-power anterior chamber intraocular lens implanted to correct high myopia. Preoperative myopia ranged from −7.00 to −24.00 D. Postoperative spherical equivalent was −0.50 D; 80.5% of eyes were within 1.00 D of emmetropia. Two years postoperatively, no cataract formation, retinal detachment, glaucoma, or significant endothelial damage had occurred. We conclude that minus-power lenses can rapidly, safely, and predictably correct high myopia in phakic patients.
Structure-function relationship between FDF, FDT, SAP, and scanning laser ophthalmoscopy in glaucoma patients.
2012
Purpose Flicker defined form perimetry (FDF) and frequency doubling technology perimetry (FDT) are alleged to detect glaucoma at an earlier stage than standard automated perimetry (SAP). It is the purpose of this study to investigate the structure-function relationship between FDF, FDT, SAP, and confocal scanning laser ophthalmoscopy (cSLO) in patients with glaucoma. Methods Seventy-six patients with glaucoma were included in the study. Patients were tested with SAP, Matrix-FDT, FDF perimetry, and cSLO. Structure-function relationships between global and sectoral cSLO parameters and global and sectoral mean sensitivity (MS) of SAP, Matrix-FDT, and FDF were calculated using Spearman's rank c…