What causes dizziness?

Diagnostic search for complaints of dizziness begins with a thorough analysis of the complaints themselves. Complaining of dizziness, the patient usually has in mind one of three sensations: "true" dizziness, which is recommended to include systemic (rotational, circular) dizziness; the state of "faintness" in the form of a feeling of general weakness, nausea, discomfort, cold sweat, a premonition of imminent falling and loss of consciousness, and finally, the third variant of vertigo implies difficult words described by the senses that sometimes arise during the movement of the patient in violation of coordination of movements, instability of the body , violations of gait of various types, visual and gaps, etc.

All three types of completely different sensations are designated by the patients in one word - "dizziness", but behind each of them there are different neurological syndromes leading to different series of diseases. The first type of dizziness is called the vestibular and is accompanied by a characteristic vestibular symptom complex; the second variant of dizziness is characteristic for lipotymic states and syncope of different nature (non-systemic dizziness); the third kind of vertigo is less likely to cause diagnostic difficulties and reflects visual-vestibular, postural, apracto-atactic and other similar disorders, which have an ambiguous, often mixed nature. Stand alone are the so-called psychogenic dizziness.

The main causes of dizziness

Systemic (vestibular) dizziness:

1. Benign positional dizziness.
2. Vestibular neuronitis.
3. Ménière's disease.
4. Herpetic lesion of the intervening nerve.
5. Intoxication.
6. An infarct, an aneurysm or a tumor of a brain of different localization (a cerebellum, a trunk of a brain, a hemisphere of the big brain).
7. Vertebral-basilar insufficiency.
8. Craniocerebral injury and post-comon syndrome.
9. Epilepsy.
10. Labyrinth or labyrinth infarction.
11. Multiple sclerosis.
12. Dysbinesia (platibasia, Arnold-Kiari syndrome and other cranio-vertebral anomalies).
13. Syringobulbia.
14. Other diseases of the brain stem.
15. Constitutionally caused vestibulopathy.
16. Arterial hypertension.
17. Diabetes.

Inconsistent dizziness in the picture of the lipotymic state:

1. Vaso-depressor (vasovagal) syncope.
2. Hyperventilation fainting.
3. Carotid sinus hypersensitivity syndrome.
4. Cough fainting.
5. A nocturnal faint.
6. Hypoglycemic syncope.
7. Orthostatic hypotension of the neurogenic (primary peripheral vegetative insufficiency) and somatogenic origin (secondary peripheral vegetative failure).
8. Orthostatic circulatory disorders in diseases of the heart and blood vessels (aortic stenosis, ventricular arrhythmia, tachycardia, fibrillation, etc.).
9. Sympathectomy.
10. Arterial hypertension.
11. Diabetes.
12. Ischemia in the region of the brainstem.
13. Anemia, acute loss of blood, hypoproteinemia.
14. Dehydration.
15. Pregnancy.

Vertigo mixed or undefined:

1. Dizziness in pathological processes in the neck (Unterharnshaidt syndrome, platibasia, Arnold-Chiari syndrome, "posterior cervical sympathetic syndrome", "whiplash" trauma, myofascial pain syndromes cervical localization).
2. Vertigo with some visual impairment and oculomotor disorders (incorrectly selected glasses, astigmatism, cataract, paresis of the oculomotor nerves, etc.).
3. Drug intoxication (apressin, clonidine, tracicore, viper, aminocaproic acid, lithium, amitriptyline, sonapaks, diphenin, phenobarbital, finlepsin, nacom, madopar, parlodel, mirapex, brufen, voltaren, phenibut, insulin, lasix, ephedrine, tavegil, oral contraceptives , midokalm, atropine, clonazepam, prednisolone and others).
4. Vertigo in patients with migraine.
5. Vertigo in the case of impaired coordination, standing and gait (dysbasia of a different nature).

Dizziness of a psychogenic nature

Systemic (vestibular) dizziness

Systemic dizziness may occur when the vestibular system is involved at any level, starting from the inner ear in the pyramid of the temporal bone, the vestibular nerve, the bridge-cerebellum angle, the brain stem and ending with the subcortical structures and the cortex (in the temporal and parietal lobes).

The final diagnosis of the level of vestibular dysfunction is established based on the indices of the vestibular passport and the concomitant neurologic symptoms.

Any processes affecting the vestibular conductors at the peripheral level (from the inner ear and the vestibular nerve to the bridge-cerebellar angle and the nuclei of the vestibular nerve in the brainstem) are usually accompanied not only by the vestibular symptom complex, but also by hearing impairment (Meniere's disease, labyrinth infarction , labyrinthitis, neurinoma of the VIII nerve, etc.), because at this level the vestibular and auditory nerves go together, forming the nervus statoacusticus. Thus, the systemic nature of vertigo and hearing loss in one ear in the absence of other neurological signs is a characteristic sign of damage to the peripheral parts of the vestibular system. In addition, during the processes of this localization, dizziness often has the nature of an acute attack (Menier's syndrome).

Ménière's syndrome consists of auditory and vestibular components. The auditory components include: noise, ringing in the ear and hearing loss on the affected side. Vestibular components are: vestibular (systemic) dizziness (visual, less often proprioceptive and tactile), spontaneous nystagmus, vestibular ataxia and vegetative disorders in the form of nausea, vomiting and other manifestations. Ménière's disease is manifested by repeated attacks, each of which can leave behind a residual residual hearing loss, which, when seizures recur, increases and ultimately leads to a pronounced decrease in hearing in one ear.

Benign paroxysmal positional dizziness is a peculiar disease of an unclear genesis, which manifests itself as short (from a few seconds to several minutes) dizzy spells arising from a change in the position of the body. In typical cases, dizziness develops in a strictly defined position of the head, changing the position of which (the patient turns, for example, to the other side) leads to the cessation of dizziness. The forecast is favorable. Benign paroxysmal positional dizziness usually passes by itself for several months. However, the diagnosis of this syndrome always requires careful exclusion of other possible causes of dizziness.

Vestibular neuronitis is also a disease with unknown pathogenesis; it often begins after acute respiratory infection, is less associated with metabolic disorders. The development of symptoms is acute: systemic dizziness, nausea, vomiting, which can last several days. The forecast is favorable. The disease completely regresses, although a "tail" of poor health is possible in the form of general weakness, mild instability, a subjective sensation of "lack of balance," especially with sharp turns of the head. In addition to the nystagmus of other neurologic symptoms, there is no syndrome.

Vertigo in processes in the area of the bridge-cerebellar angle are combined with the symptoms of involvement of other cranial nerves, primarily the roots of the facial and auditory nerves, as well as the intermediate nerve that passes between them. Depending on the size of the pathological focus and the direction of the process, trigeminal and abnormal nerves, cerebellar functions on the side of the focus, pyramidal signs on the opposite side, and even the compression symptoms of the caudal sections of the brain stem may join. As the process progresses, symptoms of intracranial hypertension (neurinomas, meniograms, cholesteatomas, cerebellar or brain stem tumors, inflammatory processes, herpetic lesions of the intervening nerve) appear. As a rule, CT or MRI is crucial in diagnosis.

Virtually any lesion of the brainstem can be accompanied by dizziness and vestibular-cerebellar ataxia: vertebral-basilar insufficiency, multiple sclerosis, platibasia, syringubulbia, vertebral artery aneurysms, IV ventricle and posterior cranial fossa (including in the picture of the Bruns syndrome).

The presence of systemic dizziness against the background of vascular disease (outside its exacerbation) in the absence of any other focal neurologic symptoms can not serve as a sufficient basis for the diagnosis of transient ischemic attack. It is known that the vestibular system is most sensitive to hypoxic, toxic and other damaging effects and therefore vestibular reactions easily develop even with relatively mild functional loads on this system (for example, vestibular-vegetative disorders in the picture of autonomic dystonia syndrome). Only transient visual and oculomotor disorders, as well as dysarthria or ataxia of mixed vestibular-cerebellar character against dizziness (both systemic and non-systemic), less often - other neurological symptoms, speak of ischemia in the brainstem. It is necessary that there are at least two of these symptoms, in order to presumably talk about TIA in the vertebral-basilar vascular pool.

Visual disturbances are manifested by blurring of vision, obscurity of vision of objects, sometimes by photopsy and falling out of fields of vision. Oculomotor disorders are often manifested by transient diplopia with structurally unstable paresis of the muscles of the eye. Characterized by instability and staggering when walking and standing.

For the diagnosis it is important that these or other symptoms of brainstem lesions almost always appear simultaneously or soon after the onset of dizziness. Episodes of isolated systemic dizziness often cause overdiagnosis of vertebral-basilar insufficiency. Such patients need a thorough examination to verify the suspected vascular disease (ultrasound of the main arteries, MRI in angiographic mode). Transient ischemic attacks in this vascular basin can also be manifested with non-systemic dizziness.

Some forms of nystagmus are never observed in the lesion of the labyrinth and are typical for the lesion of the brain stem: vertical nystagmus, multiple nystagmus, monocular nystagmus, and rarer nystagmus - convergent and retractor nystagmus).

Pathological processes in the brain or cerebellum (infarcts, aneurysms, tumors) affecting the conductors of the vestibular system may be accompanied by systemic dizziness. Diagnosis is facilitated by the identification of concomitant symptoms of hemispheric and other brain structures (conductive symptoms, signs of gray subcortical substance, forced position of the head, intracranial hypertension).

Vertigo can be part of the aura of epileptic seizure (cortical projections of the vestibular apparatus are in the temporal region and, in part, in the parietal region). Typically, these patients are identified and other clinical and electroencephalographic signs of epilepsy.

Arterial hypertension can be accompanied by systemic dizziness with a sharp rise in blood pressure. Diabetes often leads to episodes of nonsystemic dizziness (in the picture of peripheral vegetative failure).

Constitutionally-conditioned vestibulopathy is manifested mainly in increased sensitivity and intolerance to vestibular loads (swings, dances, certain modes of transport, etc.).

Incompatible dizziness in the picture of lipotomy

This type of vertigo has nothing to do with systemic dizziness and manifests itself suddenly with a general weakness, a feeling of faintness, a darkening in the eyes, a ringing in the ears, a feeling of "floating away of the soil," a premonition of loss of consciousness, which often happens in reality (fainting) . But the lipotypic state does not necessarily pass into a faint, it depends on the speed and degree of fall in blood pressure. Lipotypic conditions can often be repeated and then the main complaint of the patient will be dizziness.

Causes and differential diagnosis of lipotypic conditions and fainting (vasodepressor syncope, hyperventilation syncope, GKS syndrome, cough syncope, nocturic, hypoglycemic, orthostatic syncope of different origin, etc.), see "Sudden loss of consciousness".

With the fall of arterial pressure against the background of the current cerebrovascular disease, ischemia often develops in the region of the brainstem, manifested by characteristic stem phenomena and dizziness of a non-systemic nature. In addition to postural instability, walking and standing can take place:

1. a sense of displacement of the environment when the head turns,
2. lipotymic states with a feeling of faintness without focal neurological symptoms,
3. Unterharnshaidt syndrome (attacks of lipotomy followed by loss of consciousness, which occur when the head turns or when the head is in a certain position),
4. "Drop-attacks" in the form of attacks of sudden sharp weakness in the limbs (in the legs), which are not accompanied by loss of consciousness. In typical cases, lipotymia is also not present here. Sometimes these attacks are also provoked by head twists, especially hyperextension (overexertion), but can develop spontaneously.

Attacks develop without precursors, the patient falls, not having had time to prepare for the fall ("knees buckled") and therefore often gets damaged in the fall. The attack lasts several minutes. It is based on a transient defect of postural control. Such patients need a thorough examination to exclude cardiogenic syncope (cardiac arrhythmia), epilepsy and other diseases.

Predispose to dizziness of the second type (i.e., non-systemic vertigo) conditions associated with a decrease in blood volume (anemia, acute blood loss, hypoproteinemia and low plasma volume, dehydration, arterial hypotension).

For purely pragmatic reasons, it is useful to remember that a frequent physiological cause of non-systemic dizziness in women is pregnancy, and among pathological causes - diabetes mellitus.

Vertigo mixed or undefined

This group of syndromes is clinically heterogeneous and includes a number of diseases that are difficult to attribute to the first or second group of diseases mentioned above and accompanied by dizziness. The nature of vertigo here is also ambiguous and not always clearly defined.

Vertigo in pathological processes in the neck

In addition to the Unterharnshaidt syndrome, which has already been mentioned above, this includes dizziness in congenital bone disease (platibasia, Arnold-Chiari syndrome and others), some cervical osteochondrosis syndromes and spondylosis (eg, dizziness in the so-called posterior sympathetic syndrome). Injuries like "whip", as a rule, are accompanied by dizziness, sometimes very pronounced, as, for example, with hyperextension injury. Disturbances of balance, dizziness and some vegetative (local and generalized) complications of myofascial syndromes, especially in cervical localization of the latter, are described.

Some people who first put on glasses, especially when unsuccessfully selected lenses, have complaints of dizziness, the causal relationship of which with the state of the organ of vision may not be realized by the patient himself. As a possible cause of dizziness, such diseases as astigmatism, cataract and even oculomotor disorders are described.

Some pharmacological preparations may have dizziness as side effects, the origin of which in some cases is unclear. In the practice of a neurologist, such drugs are apressin, clonidine; tracer, vine; aminocaproic acid; lithium, amitriptyline, sonapaks; diphenin, phenobarbital, finlepsin; nakom, madopar, parlodel; brufen, voltaren; phenybut; insulin; Lasix; ephedrine; tavegil; oral contraceptives; midokalm; atropine; clonazepam; prednisolone.

Vertigo is often found in migraine sufferers. Their genesis is not entirely clear. With some forms of migraine, for example basilar, dizziness enters the picture of the attack and is accompanied by other typical manifestations (ataxia, dysarthria, visual disorders, etc., up to the disturbance of consciousness). In other forms of migraine, dizziness may be in the aura of an attack, precede an attack of cephalalgia, develop during a migraine attack (rarely), or appear independently of a headache attack, which occurs much more often.

Disturbances of balance and gait (dysbasia) associated with paretic, atactic, hyperkinetic, akinetic, apratic or postural disorders are sometimes perceived and described by patients as states resembling dizziness (eg, dysbasia in multiple sclerosis, Parkinsonism, Huntington's chorea, expressed by generalized essential tremor , normotensive hydrocephalus, torsional dystonia, etc.). Here the violation of stability and equilibrium of the patient sometimes describes, using for their designation the word "dizziness". However, the analysis of the patient's feelings shows in such cases that the patient may not have dizziness in the literal sense of the word, but there is a decrease in control over his body in the process of his orientation in space.

Dizziness of a psychogenic nature

Some of the dizziness mentioned above has already been mentioned in some psychogenic disorders: in the picture of neurogenic syncope and pre-stupor states, in hyperventilation syndrome, etc. Peculiar vestibulopathy, as a rule, accompanies protracted neurotic disorders. But there are dizziness as a major psychogenic disorder. So the patient may have a gait disturbance (dysbasia) in the form of careful slow movement along the wall due to fear of falling and feeling dizzy as the leading complaint. A careful analysis of such "dizziness" shows that under dizziness the patient understands the fear of a possible fall, which is not supported by vestibular dysfunction or any other threat of a real fall. Such patients, usually prone to obsessive disorders, have a subjective sense of instability when standing and walking - the so-called "phobic postural dizziness".

[1], [2], [3], [4], [5], [6], [7], [8]