Eye diseases. Clinical picture of glaucoma (most important)

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Eye diseases. Clinical picture of glaucoma (most important)

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46. Clinical picture of glaucoma

Open-angle glaucoma usually occurs after the age of forty. The onset of the disease is often asymptomatic. 1520% of patients complain about the appearance of iridescent circles around the light source, periodic blurred vision. Often there is an early, age-inappropriate weakening of accommodation. There are minor changes in the anterior part of the eye. The depth of the anterior chamber in the case of open-angle glaucoma is usually not changed. The clinical picture of open-angle glaucoma is characterized by the development of glaucomatous atrophy of the optic nerve in the form of marginal excavation. In this case, a whitish or yellowish ring (halo) may appear near the optic nerve head.

In gonioscopic examination, the iris angle of the anterior chamber is always open, and is usually quite wide and only in rare cases somewhat narrowed. Corneoscleral trabeculae are sclerotic. There is exogenous pigmentation of the iris angle of the anterior chamber. With open-angle glaucoma, there is a slow and gradual increase in intraocular pressure as resistance to the outflow of aqueous humor increases. The deterioration of visual functions may be a consequence of the growing phenomena of glaucomatous atrophy of the optic nerve head. Early changes in the visual field are characterized by the expansion of the blind spot and the appearance of small scotomas in the paracentral region, later turning into Bjerrum's arc scotoma.

Further development of the glaucomatous process characterizes the detection of defects in the peripheral visual field. The narrowing of the visual field occurs mainly on the nasal side (in the upper nasal sector). The late stages of the disease are characterized by concentric narrowing of the visual field and a decrease in visual acuity.

Primary open-angle glaucoma is typical for middle-aged and elderly people. Changes occurring in the body are characteristic of this age group. A number of negative factors such as low blood pressure, the presence of cervical osteochondrosis, sclerotic changes in extracranial vessels affect the course and prognosis of primary open-angle glaucoma. All these factors lead to a deterioration in the blood supply to the brain and eyes. Angle-closure glaucoma accounts for 20% of primary glaucoma cases. It usually progresses over the age of forty. It most often manifests itself in individuals with hypermetropia, since the anatomical features of eyes with such refraction (small anterior chamber and large lens) are predisposed to its development. The course of angle-closure glaucoma is characterized by periods of exacerbations and remissions. An acute attack of angle-closure glaucoma is provoked by emotional arousal, pupil dilation, copious fluid intake, overeating, cooling, body position that causes venous stasis in the eye area (with prolonged head tilt down, neck compression, etc.), drinking in a significant amount. Patients have pain in the eye, radiating along the trigeminal nerve to the forehead and temples, blurred vision, the appearance of iridescent circles when looking at a light source. Characterized by a slow pulse, nausea, and sometimes vomiting.

Author: Shilnikov L.V.

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