Fields of vision in the field of ophthalmology are an important concept in the diagnosis of various diseases. In our article, we will talk about the causes, prevention and treatment of such a pathology as visual field loss.
Brief description of pathology
Field of view is the extent of the surrounding space when looking ahead. A change in it is a symptom that indicates the presence of some kind of disease.
Loss of visual fields along with their narrowing is the main pathological symptom in the field of ophthalmology. Each patient who suffers from such a pathology experiences certain characteristic sensations in visual perception. This pathology is most accurately detected only with the help of hardware diagnostics using ophthalmic instruments.
Causes of disease
There are many reasons that can cause visual field loss. They concern not only the organs of vision, but also serve as a consequence of a serious violationin the brain. The most common causes of visual field impairment include cataracts, along with glaucoma, optic nerve pathology, eye trauma, retinal detachment, neurological disease, high blood pressure, atherosclerosis, and diabetes.
In the event that some part of the image is observed, as if through a translucent curtain, then we are most likely talking about a cataract. At the initial stage of glaucoma, the center of vision is usually affected, and only then the pathology can affect the peripheral regions. The reasons for the loss of visual fields should be identified by the doctor.
Total loss of vision
With severe pathologies of the optic nerve, the eyes completely stop seeing. Eye injuries can lead to loss of certain areas in the field of view, and at the same time to a severe limitation of vision. With retinal detachment, patients tend to see familiar objects in a distorted way. Proportions often change, and straight lines can be curved. Sometimes the patient may feel as if he is looking through a veil of fog.
Against this background, the surrounding panorama can be noticeably deformed. Extremely dangerous for the eyes are high blood pressure along with atherosclerosis. Such diseases cause the appearance of blood clots in the eye vessels. In this case, some part of the retina stops working and the patient has a dark spot in the field of view or a narrowing of the visible area is observed.
This phenomenon usually occurs spontaneously anddisappears after a while, as the thrombus is destroyed on its own. Loss of visual field is systematic. Small blood clots block the supply of blood to the retina and for a while, the affected area ceases to deliver signals to the brain. Then the blood supply is restored, after which the patient sees well again. There may be a loss of the field of view of one eye, or maybe two at once.
Development of hemianopsia
Hemianopsia is a condition when there is a unilateral and versatile loss of part of the visual fields. At the same time, the patient develops blindness in one of the halves of the visual picture. Such a prolapse indicates a pathology of the nervous system, and not an ophthalmological disease.
This disease can be temporary or permanent. It all depends on the damage to the parts of the brain. According to the classification, hemianopsia is divided into homonymous, heteronymous, bitemporal and binasal.
What does the loss of half of the field of view mean?
Homonymous hemianopsia means the presence of pathological processes in which the patient sees only one half of the visual picture. The reason for the appearance of such hemianopsia is a lesion in a specific place in the visual tract or in the cerebral cortex. According to the classification, such hemianopsia is divided into the following types:
- With the full type, there is a loss of left or right fields of vision.
- In the partial type, there is a loss of a narrow section of the visual field on the right.
- With a square type, the field of view drops out in the upper quadrant.
Causes of hemianopsia
Hemianopsia is congenital or acquired. The most common causes of visual field loss are:
- Presence of vascular lesions of the brain in the form of hemorrhagic or ischemic strokes.
- Development of brain injury.
- Presence of a brain tumor with any course (it does not matter if it is benign or malignant).
- Presence of transient or transient cerebral circulatory disorders.
- Presence of hysterical reactions, hydrocephalus, migraine and epileptic seizures.
Hemianopsia may be transient with a transient vascular disorder or migraine. The nature of such a transient disease is explained by short-term swelling of certain areas of the brain. In the event that the edema of this region of the nervous system subsides, then blindness regresses and restoration of visual function is achieved. The appearance of such a symptom in a neurological disease as hemianopia makes it possible to diagnose and clearly establish the area of brain damage.
Other types: heteronymous, bitemporal and binasal hemianopia
In heteronymous hemianopsia, nasal or temporal fields of vision fall out. The boundary between the displayed and lost parts of the fields runs horizontally. Such hemianopsia, according to the nature of the loss of lateral visual fields, is also divided into partial, complete or square scotoma.
With bitemporal type (this is the mosta common type of pathology) there is a loss of the temporal half of the visual field synchronously in both eyes. Such a disease can develop in the presence of basal arachnoiditis or aortic aneurysm. Brain damage is observed in the region of the pituitary gland or in the areas of the optic nerves.
With the binasal type, the nasal half of the visible field is lost on both sides. This type of hemianopia rarely develops and is usually diagnosed with chiasmatic arachnoiditis, as well as developing hydrocephalus and the presence of a tumor process in the brain.
Diagnostics
Diagnosis of such a disease is carried out taking into account the study of visual fields using computer perimetry. The presence of clinical symptoms of the disease, as a rule, is confirmed by additional laboratory tests.
Often, the symptoms of hemianopsia indicate the presence of a serious brain lesion. In order to clarify the diagnosis, computed tomography is performed, as well as magnetic resonance imaging and radiography of the skull. How is visual field loss treated?
Treatments
The treatment of hemianopsia is aimed at eliminating the underlying causes of the disease. The sooner treatment procedures are started to eliminate the underlying disease, the more favorable the prognosis for the patient's future life can be. As a rule, any neurological ailments leave behind persistent organic changes incentral nervous system.
Payed cerebrovascular accident, head trauma, as well as surgical removal of a brain tumor requires long-term rehabilitation against the background of residual effects of these diseases. Rehabilitation of patients suffering from the pathology in question should be carried out not only with medications.
It is necessary to adapt such patients for orientation in the outside world. Wearing glasses with special mirrors can be of great help in this. Also beneficial are classes in specially designed programs that are aimed at improving vision.
Forecast
The prognosis for the life of patients with this disease, unfortunately, is unfavorable. Basically, this ailment of an organic nature remains in a person, and the symptoms do not regress.
A positive prognosis is noted only when a person, after a stroke, which was transferred in the form of a transient circulatory disorder of the brain, leaves his painful state without any consequences. The symptoms of the disorder regress along with the manifestations of hemianopia. It is this development of symptoms that is observed in migraine, and, moreover, against the background of epileptic seizures and in hysterical reactions. In all such cases, positive dynamics in the disease and a good prognosis for the future are noted.
It is worth mentioning both prevention and what needs to be done to prevent the occurrence of such a disease.
Prevention of pathology
In the role of preventive measures to reduce the risk of eye diseases, people should be advised to comply with the work regime and rest. This is especially true for those people who constantly work on a computer, as well as in hazardous industries. Persons with high blood pressure, just like diabetics, need to constantly monitor the slightest negative deviations in their he alth.
In order for the risks of developing the disease in question to be minimal, it is necessary to carefully monitor the state of he alth and in no case allow injuries to the head and neck. Among other things, it is necessary to be attentive to the state of he alth of the heart and blood vessels, and at the same time to conduct a systematic examination by a cardiologist.
In case of detection of unpleasant symptoms, loss of visual fields of any nature, the patient should immediately and without delay consult a doctor. This will certainly ensure the timely determination and diagnosis, which means that the necessary treatment will be started on time. This will make it possible to eliminate the he alth problem at the beginning, and at the same time prevent the development of a possible complication.
