Nystagmus - what is it and how is it treated?
If a person cannot focus his gaze on one point due to the fact that his eyeballs make involuntary oscillatory movements, with a high degree of probability we can say that this is nystagmus.
- Eyeball nystagmus - what is it?
- Symptoms of nystagmus
- Causes of nystagmus
- Types of nystagmus
- The degree of nystagmus
- Operation to eliminate nystagmus
- Complications of nystagmus
- Nystagmus in children
- Disease prognosis
Eyeball nystagmus - what is it?
With nystagmus, the eyeballs repeat the same vibrations, and this process cannot be controlled by any effort. Nystagmus occurs even in healthy people after a rapid rotation of the body, or when following a rapidly moving object. However, most often, this pathology is based on damage to the central nervous system, a disease of the inner ear, and visual impairment.
If nystagmus occurs due to a violation of the functionality of an organ, it is necessarily accompanied by a decrease in visual acuity. The share of eyeball nystagmus among all eye diseases is 18%, among visually impaired children from 20 to 40% of patients suffer from nystagmus.
The eyeballs make spontaneous movements due to increased tone on one side of the labyrinth of the inner ear. Normally, the signal transmitted from this vestibular analyzer reaches the eyeballs at the same speed. This synchronicity allows the eyes to make the same movements or remain still. With a disease, hypertonicity of the labyrinth of the inner ear disrupts the coherence of the signals of the vestibular apparatus, the eyeballs involuntarily oscillate in different directions.
If nystagmus appears when the position of the body changes, then the pathology has spread to the semicircular tubules of the inner ear.
Symptoms of nystagmus
The manifestations of the disease depend on its type. Since nystagmus occurs against the background of the underlying pathology, at the same time the patient experiences the full severity of the symptoms of the underlying disease. Common to all types of nystagmus is the oscillatory movement of both eyeballs, which is uncharacteristic for a healthy person, which can be both friendly and multidirectional. They move in a circle, diagonally, up and down, or left and right.
- Frequent dizziness;
- Violation of the adaptation process to changes in external conditions;
- Blurring of objects falling into the field of view, or their shaking.
If the patient changes the direction of gaze, the position of the head or focuses the gaze on the object as much as possible, the amplitude of the oscillations of the eyeball decreases slightly, although it cannot be completely stopped.
To reduce the manifestations of nystagmus, the patient tries to take exactly the position of the head, in which the movements of the eyeball are minimal, its accommodation improves. Most often these are tilts or turns of the head to the side. The symptoms of the disease are aggravated by stress and excitement, during fatigue. These manifestations are influenced by a change in mood, the size and brightness of the object, and visual concentration.
The eyeballs can make the same movements, or move in different directions with different patterns of vibration.
The nature of movements with nystagmus:
- Pendulum - with the same amplitude;
- Jerky - the eyes move slowly to one side, and quickly to the other;
- Mixed - both types of vibrations occur in one case.
In addition to local clinical manifestations, the patient has general symptoms of the disease - weakness of muscle tone, uncertain gait, hearing impairment on one or both sides, deterioration in general well-being.
Causes of nystagmus
At the heart of congenital nystagmus is a violation of the functioning of the central nervous system. Clinical symptoms appear against the background of albinism or congenital damage to light-sensitive cells of the retina (Leber's amaurosis).
Reasons for acquired nystagmus:
- Traumatic brain injury with damage to the occipital area of the cerebral cortex or optic nerve;
- The consequences of a stroke or multiple sclerosis;
- Malignant brain tumor;
- CNS intoxication with alcohol, overdose of barbiturates or anticonvulsants;
- Injury or disease of the inner ear;
- Decreased visual acuity with cataracts, eye injury, or complete blindness;
- Birth trauma, pathology of the intrauterine period;
- Consequences of neuroinfections affecting the cerebellum, cerebral cortex, medulla oblongata.
In a healthy person, nystagmus of the eyeball occurs when there is a violation of orientation in space, and disappears in a calm state. If recovery does not occur, it means that the nervous system is not able to return to its previous positions due to pathology.
Types of nystagmus
Experts divide nystagmus into congenital and acquired forms. Congenital nystagmus is divided, in turn, into latent and manifest-latent type, and acquired - into neurogenic and vestibular type.
Horizontal nystagmus. In this type of pathology, the movement of the eyeball is directed horizontally, that is, left and right. Most likely, the cause of the disease is damage to the inner ear or the middle parts of the rhomboid brain, which connects the brain and spinal parts of the central nervous system.
Vertical nystagmus. With vertical nystagmus, the eyeball moves vertically, that is, up and down. Appears when the dosage of barbiturates is exceeded or pathologies of the upper brain stem.
Rotatory nystagmus. Torsional, or rotatory nystagmus, appears when the body rapidly rotates around its axis. The eyeball immediately after stopping moves in the opposite direction, during rotation it makes movements with a large amplitude in the direction of rotation.
Spontaneous nystagmus. In spontaneous nystagmus, the eyeballs move involuntarily at a high frequency. The spontaneous form of nystagmus can be diagnosed in a healthy person when he observes a rapidly moving object or spins himself at a high speed. Most often, the direction of movement of the eyeball occurs in the horizontal plane.
There are jerky and pendulum-like types of spontaneous nystagmus:
- Pendulum nystagmus - eye movements resemble a sinusoid or swing of a pendulum;
- Jolt-like nystagmus - the eyeball moves quickly in one direction, and slowly in the other.
Due to a very low level of vision (more than 6 diopters), nystagmus can manifest itself as a violation of gaze fixation.
Small-sweeping nystagmus. With this type of nystagmus, the eyeballs make a small amplitude of oscillations (no more than 5-6 °) in the horizontal direction. The disease is directly related to the pathology of the inner ear, its labyrinth. The eyeballs move involuntarily.
Installation nystagmus. With this form of pathology, the eyeball makes fine-sweeping rhythmic movements that occur when looking to the side, when the eye muscles are extremely tense.
Congenital nystagmus. This type of visual anomaly manifests itself immediately after the birth of a child and retains its symptoms throughout a person's life. Most often it takes a horizontal or jerky shape.
Varieties of congenital nystagmus:
- Optical - one of the most severe visual disorders, is diagnosed at 2 months of a child's life, has a pendulum shape, the amplitude of movements decreases when trying to focus the gaze on one object;
- Latent - the disorder occurs when trying to close the eye with the eyelid in a child with strabismus, takes a jerky shape, the fast phase of movement is directed towards the open eye;
- Nodding spasm is a rare visual disorder, diagnosed at the age of 4-14 months, its characteristic symptom is torticollis, mismatch of head movement with eye movements.
The degree of nystagmus
There are 3 degrees of nystagmus:
- If the eye is at rest, nystagmus is absent, but manifests itself with extreme abduction of the organ of vision towards the fast phase.
- Pathology manifests itself when the eye is in a central position.
- Nystagmus manifests itself with extreme abduction of the eye towards the slow phase. In the third degree, the eyeball vibrates in the opposite direction.
The main method for diagnosing nystagmus is an examination by an ophthalmologist to determine the acuity and field of view of the state of the fundus and optical media of the eye. The doctor immediately notes the presence of involuntary eye movements, asks the patient to fix his gaze on the tip of a pencil or a special pointer. The ophthalmologist moves the pointer in different directions, with the help of this technique sets the type of nystagmus.
Additional diagnostic methods:
- Magnetic resonance imaging or computed tomography - helps determine the presence or absence of brain tumors as a possible cause of nystagmus;
- Microperimetry - used to determine the parameters of nystagmus, study the sensitivity of the retina;
- Echoencephalogram (echo-eg);
- Refractometry - used to determine the type of refraction, the presence of myopia, hypermetria;
- Electronistamography - used to determine the potential difference between the cornea and the retina, the increase in which is characteristic of this pathology;
- A blood test to determine the concentration of toxins in the body;
- Determination of visual evoked potentials;
- Consultation with a neuropathologist, opolaryngologist and neurosurgeon.
Visual acuity is determined in different situations - with and without glasses, with a normal head position or in a forced position. On a detailed examination, the doctor can detect in the patient atrophy of the optic nerve, pigmentary degeneration of the retina, opacity of the lens and cornea, macular coloboma.
Treatment of nystagmus
To eliminate nystagmus, the doctor treats the underlying disease that caused the pathology. The therapy of the disease is rather long and complicated, it includes optical vision correction, drug treatment, and surgical methods.
Optical correction. To mitigate visual acuity disorders, the doctor carefully selects the patient glasses or contact lenses to examine objects near and far. If the patient suffers from albinism, he has retinal dystrophy or optic nerve atrophy, glasses with orange, yellow, brown or neutral light filters are used. Dense light filters protect the eyes from the negative effects of the environment, provide the best possible visual acuity.
Pleopathic treatment. To normalize amblyopia and increase the accommodative capabilities of the eyes, exercises to stimulate the retina are prescribed:
- Monobinoscope highlights using a red filter to stimulate the central retina;
- Color and contrast-frequency tests on a computer and an illusion device (spider, Zebra, Crosses).
To reduce the amplitude of nystagmus and increase the level of vision, methods of diploptic treatment are used:
- Binocular exercises.
The technique of using the exercises provides for their implementation first for each eye separately, then for both eyes simultaneously.
Medical treatment. Treatment with drugs is not the main method, it is auxiliary in nature.
The main groups of drugs:
- Vasodilators - Theobromine, Cavinton, Angiotrophin, Trental;
- Preparations for improving eye nutrition - Actovegin;
Operation to eliminate nystagmus
Correction of nystagmus in the punctate form of this pathology consists in weakening the strong muscle on the side of the strong phase and strengthening the weak muscle on the side of the weak phase. Thus, the median position of the relative rest of the eyes is fixed:
- Bilateral symmetrical intervention (recession) on the muscles responsible for the slow phase.
- With a sharp decrease in nystagmus, the second stage is not performed. In the absence of effect, bilateral symmetrical intervention (recession) is performed on the muscles responsible for the fast phase.
When nystagmus is combined with strabismus, a smaller resection is performed on the side of the deviation, and a larger resection is performed on the side opposite to the deviation. The use of laser and radiotherapy methods allows you to maximize the preservation of the nerve endings and blood vessels of the eyes. After surgery, it is required to consolidate the results by methods of conservative therapy.
According to medical statistics, successful rehabilitation is guaranteed in 78% of cases of surgical intervention. The patient gets the opportunity to have an even gaze with confident fixation on the object, high visual acuity without the use of glasses, the ability to perceive 3D format.
Complications of nystagmus
The most common complication of nystagmus is strabismus, or strabismus, in which the eyes look in different directions, and the gaze axes cannot be brought to one point.
- Amblyopia - unilateral visual impairment, in which one eye does not participate in the process of vision, is inactive;
- Astigmatism - light rays are scattered, and create a blurry image on the retina;
- Impaired coordination of movements;
- Compensatory torticollis arising from the need to keep the head in an unusual position;
- Labyrinthitis is an inflammation of the tissues of the inner ear.
Nystagmus in children
Immediately after the birth of a child, it is impossible to immediately diagnose nystagmus, since newborns are characterized by a lack of fixation of the gaze on the object. If at the age of 1-1.5 months the baby does not fix his gaze on the toy, the ophthalmologist may suspect that the child has nystagmus of the eyeball.
You can definitely say this in the second or third month of a child's life. In the first year of life, the visual apparatus is still developing, therefore, up to a year, babies are not diagnosed with nystagmus of the eyeball, until this age it is not considered a deviation. If there are compelling prerequisites for making this diagnosis, a neurologist and ophthalmologist monitors the child's health.
Possible causes of nystagmus in children:
- Pathology of intrauterine development;
- Birth injury;
To preserve the visual acuity of the child, he is carefully examined, the wearing of special glasses and other complex measures (hardware and surgical treatment) are prescribed. If the treatment is carried out correctly and in a timely manner, visual acuity in children does not deteriorate.
With adequate treatment of the underlying pathology that caused visual impairment, nystagmus of the eyeball can be eliminated almost completely. Visual functions are restored, the quality of life does not suffer.
To prevent the appearance of nystagmus, it is necessary to diagnose and treat pathologies of the brain, eyes and inner ear in a timely manner. If nystagmus appears as a complication in patients taking sleeping pills and anticonvulsants, a dosage adjustment is required.
The author of the article: Degtyareva Marina Vitalievna, ophthalmologist, ophthalmologist