Retinal migraine is a separate type of paroxysmal migraine headache, characterized by the presence of transient visual disturbances in the form of monocular single /multiple falls in the field of vision or complete blindness in one eye. The duration of visual impairment is characteristic, not exceeding 1 h. Retinal migraine is diagnosed on the basis of clinical criteria and episodes of visual impairment recorded by a doctor or patient. Additional studies (EEG, ophthalmoscopy, Doppler ultrasound, MRI, etc.) are aimed at excluding other pathology, which may also be the cause of visual field defects. Treatment consists in selecting the optimal drug, eliminating the effects of provoking factors, normalizing lifestyle.
Retinal migraine is a paroxysmal cephalgia (headache), whose attacks are accompanied by transient visual disorders in the form of a visual field defect or complete blindness (amaurosis). A blind spot in the visual field is called a scotoma and can have different localization and shape. The International Classification of Cephalgia identifies about 18 types of migraines. Among them, retinal migraine is one of the rarest forms. It is rarely found in isolated form, more often its paroxysms are combined with attacks of ophthalmic or simple migraine. The prevalence of pathology is poorly studied due to the lack of its controlled screening. Retinal migraine is of practical interest to specialists in the field of neurology and ophthalmology.
The occurrence of retinal migraine is associated with a temporary spasm of the central retinal artery. Some researchers assign a leading role in the pathogenesis of such a spasm to serotonin, a biogenic amine, the release of which from platelets is observed at the beginning of a migraine attack. As a result of the spasm, transient (i.e. reversible) ischemia of a certain part of the retina develops, leading to the loss of their ability to perceive light stimuli. As a result, a scotoma is formed. With ischemia of several areas of the retina, the scotoma is multiple in nature, and with damage to almost the entire area of the retina, amaurosis is observed. Taking into account the etiopathogenesis of visual disorders, retinal migraine is also called retinal.
The triggers that trigger a migraine attack are very individual. Among them are hypothermia, stress, physical fatigue, lack of sleep, changes in weather conditions, sensory hyperstimulation (noise, unpleasant odor, flickering light, etc.), the use of certain foods (celery, chocolate, citrus fruits, nuts, cheese, red wine, etc.); in women — menstruation, hormonal contraceptives. Researchers note that not the last place in the genesis of migraine paroxysms in general and retinal migraine in particular is occupied by increased irritability, discontent, anger. In addition, the familial nature of migraine observed in most patients suggests the idea of inheriting a certain predisposition to this pathology.
Clinically, the retinal form of migraine is manifested by attacks of hemicrania (pain in one half of the head), combined with visual impairment lasting no longer than 1 hour in the form of the formation of one or multiple cattle or complete blindness. Visual disturbances can precede hemicrania, while they occur no earlier than 1 hour before the headache appears. In other, rarer cases, retinal migraine is characterized by visual disturbances that appear after the onset of cephalgia. Scotomas and amaurosis are always observed homolaterally. that is, on the same side as the headache.
Retinal migraine can begin with the appearance of one scotoma, then there are many defects in the visual field, which, merging, can lead to complete blindness in one eye. Often the attack is accompanied by a feeling of pressure on the eyeball from the inside, subfebrility, nausea, hyperesthesia (hypersensitivity) to various external stimuli (light, sound, smell).
Retinal migraine is characterized by a short duration of attacks. An important clinical criterion is the complete restoration of visual function no longer than 1 hour after the onset of disorders, and the absence of similar vision problems in the period between paroxysms.
The basis for verifying the diagnosis of “retinal migraine” are clinical criteria and the exclusion of other possible causes of similar visual disorders. When making a diagnosis , the neurologist determines whether the symptoms correspond to the following diagnostic criteria:
- the presence of at least 2 paroxysms of headache that meets the criteria of migraine, appearing no later than 1 hour or during visual disturbances. The latter are transient in nature and last no more than 1 hour. Visual disorders must be confirmed either by the patient himself by depicting the resulting visual defect in the drawing, or by a doctor examining the patient during paroxysm.
- absence of pathological changes during ophthalmological examination in the period between migraine attacks
- absence of other causes of visual disorders.
The neurological status of the patient is within normal limits. An examination by an ophthalmologist, including the determination of visual acuity, perimetry, ophthalmoscopy, does not reveal deviations in the inter-approach period, during the period of paroxysm determines the presence of one or multiple defects in the field of vision, homolateral headache. In order to exclude other pathologies (cerebral vascular aneurysms, intracerebral tumors, optic neuropathy, retinopathy, TIA or ischemic stroke, dyscirculatory encephalopathy), EEG, echoencephalography, REG, ultrasound of the ocular vessels, MRI of the brain, scanning tomography of the retina is performed.
Unfortunately, clinicians sometimes confuse the concept of “retinal migraine” with ophthalmic migraine. At the same time, these are 2 completely different forms of migraines. Retinal migraine develops due to retinal artery spasm, and ophthalmic migraine develops due to transient ischemia of the structures of the occipital cortex. A distinctive feature is the monocular type of disorders in the retinal form of migraine and binocular in ophthalmic.
Ophthalmic migraine is a classic migraine with aura. It is characterized by a longer duration of paroxysm, the appearance of meningeal, cerebral and vegetative manifestations. Visual disorders with it are expressed in the form of lightning-like flashes, sparkling dots, light zigzags or balls. Defects in the visual fields are observed in the form of hemianopsia or narrowing of the visual fields.
To date, doctors do not have an effective and unambiguous method of treating migraines. Depending on the characteristics of the patient, the frequency and severity of paroxysms, retinal migraine is an indication for the appointment of anti-inflammatory drugs (naproxen, diclofenac, ibuprofen), combined analgesics, narcotic analgesics (tramadol, fentanyl), anticonvulsants (valproates, carbamazepine, topiramate), serotonin agonists (risatriptan, sumatriptan, eletriptan), ergot preparations (ergotamine, dihydroergotamine), beta-blockers (propranolol, metoprolol), antidepressants (milnacipran, amitriptyll, venlafaxine), antiemetics (domperidone, metoclopramide).
As a rule, the drug most suitable for stopping the attack of retinal migraine is selected experimentally. A method of treatment in the interparoxysmal period that has proven effectiveness does not yet exist. According to studies, more than 70% of patients remain dissatisfied with the results of therapy.
Prognosis and prevention
The prognosis of migraine in terms of recovery is doubtful. However, patients who make their own efforts to overcome migraine (exclude the impact of trigger factors, including changing their own negative reactions to more benevolent behavior) often achieve success. In addition, retinal migraine loses its frequency and intensity with age.
Preventive measures are mainly secondary in nature and consist in preventing another migraine paroxysm. Among them, it is possible to distinguish avoidance of provoking factors, compliance with adequate labor, food and psycho-emotional regime. If the patient could not avoid the impact of a potential trigger (for example, a stressful situation or visual hyperstimulation occurred), the use of relaxation methods, preventive intake of a pre-selected drug will help him to avoid the attack of retinal migraine.