Ocular Fundus (ocular + fundu)

Distribution by Scientific Domains

Selected Abstracts

1,25(OH)2 vitamin D concentration in the plasma of Solanum glaucophyllum intoxicated rabbits

Objective To test Solanum glaucophyllum calcinotic effects in adult New Zealand White rabbits in relation to cumulative dose and active principle concentration in plasma. Design An intoxication assay with controls. Procedure Rabbits were orally dosed with aqueous extracts of dry leaves of S glaucophyllum for 5, 7 or 9 days. During the experiment, body weight, calcaemia and phosphataemia were measured; retinal blood vessel calibre was observed by ophthalmoscopic examination of the ocular fundus. 1,25(OH)2 vitamin D plasma concentration was determined at the end of the experimental periods. Soft tissue calcium concentration and the presence of calcinotic lesions were studied after euthanasia. Results Toxic effects were evident in S glaucophyllum treated groups (loss of body weight, elevation of soft tissue calcium concentration, and presence of calcinotic lesions). Plasma 1,25(OH)2 vitamin D concentrations were negatively correlated with final body weight(r = -0.97; P = 0.001), and positively correlated with renal calcium concentration (r = 0.74; P = 0.02). There was also a significant regression of plasma 1,25 (OH)2 vitamin D concentration on the cumulative dose of S glaucophyllum(R2= 0.87; P £ 0.001). Conclusions The procedure described here offers a sensitive and practical experimental model for the study of the pathogenesis of enteque seco. [source]

Topography of solitary congenital hypertrophy of the retinal pigment epithelium in the ocular fundus

Jørgen Krohn
No abstract is available for this article. [source]

Automated quality evaluation of digital fundus photographs

Herman Bartling
Abstract. Purpose:, Retinal images acquired by means of digital photography are often used for evaluation and documentation of the ocular fundus, especially in patients with diabetes, glaucoma or age-related macular degeneration. The clinical usefulness of an image is highly dependent on its quality. We set out to develop and evaluate an automatic method of evaluating the quality of digital fundus photographs. Methods:, A method for making a numerical quantification of image sharpness and illumination was developed using MatlabÔ image analysis functions. Based on their sharpness and illumination measures, 1000 fundus photographs, randomly selected from a clinical database, were assigned to four predefined quality groups (not acceptable, acceptable, good, very good). Six independent observers, comprising three experienced ophthalmologists and three ophthalmic nurses with extensive experience in fundus image acquisition, classified a selection of 100 of these images into the corresponding quality groups. Results:, Automatic quality evaluation was more sensitive than evaluation by human observers in terms of ability to discriminate between good and very good images. The median concordance between the six human observers and the automatic evaluation was substantial (kappa = 0.64). Conclusions:, The proposed method provides an objective quality assessment of digital fundus photographs which agrees well with evaluations made by qualified human observers and which may be useful in clinical practice. [source]

Vitreous surgery for macular hole in patients with Vogt-Koyanagi-Harada disease

Izumi Kobayashi MD
Abstract We describe two patients with Vogt-Koyanagi-Harada (VKH) disease, both in the convalescent stage, who presented with unilateral macular holes together with clinically significant epi-retinal membranes. Vitreo-retinal surgery was performed on the affected eyes and the surgical technique involved a standard three-port vitrectomy, peeling of the epi-retinal and internal limiting membrane (ILM). In both cases the retinae were tamponaded with air resulting in anatomical closure of the macular holes. The histology of the excised membrane was available in one case and this revealed multiple layers of presumed retinal pigment epithelial cells with cytoplasmic processes and intercellular junctions forming a basal lamina attached to the smooth surface of the ILM. Our findings demonstrate that macular holes can develop in patients with VKH but that the hole can be successfully closed with vitreo-retinal surgery. The convalescent stage tends to occur several weeks after the acute stage when the uveitic process has subsided and is characterized by choroidal depigmentation, producing a sunset glow appearance to the ocular fundus. Patients may also demonstrate varying degrees of cutaneous hypopigmentation, poliosis and/or alopecia. Macular holes have also been reported previously in patients during the convalescent stage of VKH and this communication describes the outcome of two patients who underwent vitreo-retinal surgery for this problem. [source]