Asthenopia is a functional visual disorder that is accompanied by increased fatigue when performing visual work. It is clinically manifested by a burning sensation, pain, hyperemia, the appearance of fog in front of the eyes, a feeling of sand, as well as a decrease in visual acuity that develop after intense or prolonged visual work. Diagnosis is based on the determination of visual acuity, refractometry, biomicroscopy, accommodation study. Therapeutic measures include correction of ametropia, conservative therapy, as well as methods of hardware treatment.
H53.1 Subjective visual disorders
Asthenopia is a pathological condition manifested by a complex of subjective symptoms of visual fatigue. In practical ophthalmology, this pathology is considered as a borderline state between functional visual impairment and the initial stage of the formation of organic eye disease. Visual fatigue is equally common among men and women. Racial and age characteristics are not noted. More than 75% of the world’s population report asthenopic complaints during or after working with electronic devices. The risk group for developing asthenopia includes people whose professional activity is associated with prolonged fixation of vision at a short distance.
Causes of asthenopia
Asthenopia is a multifactorial pathology in which certain etiological factors are triggers in the development of individual pathogenesis mechanisms. Prolonged work with electronic devices, reading in low light, working with small objects, driving in bad weather conditions and non-compliance with the rules of visual hygiene are predisposing factors to the development of accommodation spasm.
Asthenopic complaints also develop with a decrease in accommodation capacity caused by hypermetropia, astigmatism, hypotrophy or violation of innervation of the ciliary muscle. The spastic state of the muscular apparatus of the eyeball for a long period of time is clinically manifested by rapid visual fatigue.
The provoking factor in the development of asthenopia is a violation of coordination between accommodation and convergence, as well as an increase in the load on the internal rectus muscles of the eye, which in turn acts as a predictor of myopia. The appearance of a number of asthenopic complaints is associated with the development of dry eye syndrome, because with prolonged concentration of attention, the number of blinks per unit of time decreases. This leads to a decrease in the secretion of secretions by the meibomian glands.
Violation of the processing of visual signals into nerve impulses occurs with neuroreceptor exhaustion of the visual analyzer, which is manifested by symptoms of asthenopia. A certain role in the development of visual fatigue is played by a low level of psychological adaptation to visual work. Thus, on the basis of etiology and pathogenesis, such forms of asthenopia as accommodative, muscular, neuroreceptive and psychoemotional are distinguished.
Symptoms of asthenopia
The clinical course is characterized by the stages of the process. There is a stage of compensation, subcompensation and decompensation. With asthenopia, at each stage, it is possible to develop such nonspecific symptoms as headache, irritability, general weakness.
At the compensation stage, short-term violations of visual functions that do not go beyond the aisles of physiological boundaries are possible. Therefore, compensated asthenopia is considered to be visual discomfort, which develops after a visual load and is leveled after a planned rest, without reducing the ability to work. Clinically manifested by a burning sensation, increased lacrimation, hyperemia, the appearance of fog in front of the eyes.
At the stage of subcompensation, a prolonged visual impairment develops, which is potentially reversible. The symptoms of this stage are characterized by the addition of a feeling of pain, sand in the eyes, distortion or doubling of the image. Functional disorders of visual function may occur 1-2 days after rest or occur after a slight load with short periods of remission.
The decompensation stage is manifested by the classic symptoms of visual fatigue. In the anamnesis, patients have frequent development of blepharitis, conjunctivitis. The main difference is the irreversibility of refraction and accommodation changes. Therefore, at this stage, the appearance of an early presbyopia clinic, the development and progression of myopia is possible.
Patients with asthenopia are recommended to undergo an annual examination by an ophthalmologist with an additional examination of the fundus and measurement of intraocular pressure. The complex of diagnostic measures includes:
- Visometry. By the method of visometry, it is possible to determine the degree of change in visual acuity. Patients with asthenopia have a tendency to develop myopia. It is very important to conduct research in dynamics. Before choosing a treatment tactic, visual acuity should be measured after a long rest from visual loads, which will make it possible to obtain true values, and not accommodation caused by spasm.
- Study of accommodation. It is one of the key methods for the diagnosis of asthenopia and includes proximetry, width measurement, determination of volume and tension of accommodation capacity. In patients with increased visual fatigue, there is a shift of the point of clear vision towards myopia. During the proximetry, patients note the early appearance of symptoms such as double vision, vagueness of the text, low ability to fix the gaze, the development of burning and pain. The desired width, volume and tension of accommodation often make it possible to establish the progression of myopia.
- Refractometry. The purpose of refractometry in patients with asthenopia is to detect myopia or astigmatism, as well as early changes in refraction. The advantage of using this method in people with increased visual fatigue is that the device gives the result of averaged values after several measurements in a row.
- Biomicroscopy. The method allows a detailed examination of the anterior parts of the eyeball. It is important in patients with decompensated asthenopia, because it allows you to diagnose conjunctivitis, assess the nature of changes, as well as the effectiveness of the treatment.
Treatment of asthenopia
Treatment of asthenopia is based on an integrated approach. Patients at the stage of compensated visual fatigue in the absence of organic changes are recommended to alternate the rest regime with visual loads. At the stage of compensation and subcompensation, it is advisable to prescribe methods of hardware vision treatment. Their list includes:
- Accommodotrener. The range of applications of the accommodotrener is quite wide. With the help of this device, it is possible to eliminate residual phenomena of accommodation spasm in patients with compensated asthenopia, as well as to perform optical correction of myopia and the initial stages of hypermetropia development.
- Laser stimulation. Stabilizes the work of the retinal receptor apparatus and provides a decrease in the tone of the ciliary muscle. Indications for this type of hardware treatment are neuroreceptive asthenopia, as well as astigmatism, myopia, hypermetropia, computer vision syndrome, accompanied by asthenopic complaints.
- Sidorenko’s glasses. The effectiveness of asthenopia treatment with Sidorenko glasses is achieved thanks to vacuum massage of the eyes and surrounding structures. Massaging movements stimulate regional microcirculation and improve trophism.
In patients with visual fatigue at the stage of decompensation or ametropia in the anamnesis, it is necessary to correct it with glasses or contact lenses. Conservative therapy consists in prescribing a course of short-acting mydriatics. The duration of the course of application of drops depends on the stage and severity of the course of asthenopia.
Prognosis and prevention
The prognosis for asthenopia depends on the stage of the disease. With the normalization of visual load at the compensation stage, complete restoration of visual function is possible. Adequate treatment at the stage of subcompensation can ensure the reverse development of the process, so the prognosis is favorable. With decompensation, as a rule, complete recovery cannot be achieved.
Prevention of asthenopia consists in alternating visual loads with rest periods, as well as the correct organization of the workplace. Patients with asthenopia are shown taking vitamins for the eyes. Before the predicted visual work, it is recommended to instill moisturizing drops into the eyes. At home, to reduce the spasm of accommodation, you should use special glasses with small perforations and do eye exercises.