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30. Possible pathological processes in the retina
Pigmentary degeneration (degeneration) of the retina.
From the anamnesis of patients with retinitis pigmentosa, characteristic complaints of poor vision at dusk are revealed. Objectively determined concentric narrowing of the field of view, impaired dark adaptation. The optic disc is waxy, the retinal vessels, especially the arteries, are constricted. On the periphery of the fundus, there is an accumulation of pigment in the form of "bone bodies". The field of view gradually narrows to a tubular one, the process always ends in blindness due to the death of photoreceptors and atrophy of the optic nerve. The disease is often bilateral and may present in early childhood; in half of the cases is hereditary.
Retinal macular degeneration. Patients complain of a decrease in visual acuity, they note that they are better oriented in the evening than in the afternoon. With ophthalmoscopy in the area of the macula, pigmented and yellowish dotted foci are determined. When examining the visual field, a relative central scotoma is determined, as well as a violation of color perception for red and green colors.
The disease is bilateral and often has a family-hereditary nature.
Macular degeneration in Tay Sachs disease is a systemic disease that is detected in children four to six months old, manifested by mental retardation, seizures, and muscle weakness due to fatty degeneration of ganglion cells in the retina and brain. In the area of the macula, such children have a degenerative white lesion with a bright red round spot in the center. The child, as a rule, goes blind and dies before reaching the age of two.
retrolental fibroplasia. Every premature newborn, especially if he was in an oxygen tent, should be examined by an optometrist. These children may develop retrolental fibroplasia of retinopathy of prematurity.
It occurs in both eyes of children in incubators already in the second to fifth week after birth.
There are three periods of the course of the disease. The first period (the acute phase lasting from three to five months) is characterized by the presence of retinal edema, vasodilation, and gentle diffuse opacification of the vitreous body on the periphery of the fundus.
The second period (regression period) is characterized by the spread of newly formed vessels with their supporting tissue from the area of retinal changes into the vitreous body, the appearance of hemorrhages, and retinal detachment.
In the third period (cicatricial phase), a significant mass of opaque tissue, foci of proliferation covering most of the retina, are determined in the vitreous body. Fibrous masses gradually fill the entire vitreous body up to the lens.
Author: Shilnikov L.V.
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