Metamorphopsia

The ability of our brain to receive and transform information coming through the senses allows us to adapt to the world around us, navigate, and learn about it by analyzing and synthesizing primary sensory-figurative reflections of objects and phenomena. Perception is a complex process of psychosensory synthesis, including not only the primary analysis of objects and phenomena, but also the cognitive processing of their display. The mechanism of reality reflection can be disrupted at any level of perception, and then the information is perceived by the individual in a distorted form. Unlike hallucinations and illusions, metamorphopsia is a disorder of the process of perceiving quantitative characteristics (number, size, shape, spatial placement, speed, direction of movement, etc.) of real and correctly identified objects. Distortion of information occurs after it has been, for the most part, correctly perceived at the level of the visual organs. In most cases, people critically assess their condition, realizing that their perception does not correspond to reality. This leaves them confused and concerned about their condition, and in more severe cases, it makes them suffer from the inability to function normally in society.

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Epidemiology

The statistics of this phenomenon are not fully presented, since it is detected infrequently and in completely different diseases. It is believed that the probability of metamorphopsia does not depend on gender. Micropsia - the perception of objects of the surrounding world as smaller than they are in reality, is more common in childhood from five to twelve years.

Refractive metamorphopsia can be quite common, as astigmatism and myopia are common, but they are well corrected with glasses (lenses) or surgery, so they do not cause any particular inconvenience in everyday life. Pathologies of the macula of the retina are also not too rare. However, with ophthalmological diseases that cause distorted perception of visual images, everything is more or less clear. With successful vision correction, the patient's condition normalizes.

Metamorphopsia in people without visual pathologies is much more worrisome. Alice in Wonderland syndrome is often experienced by people with affective disorders. WHO statistics claim that every fourth inhabitant of the planet suffers from a mood disorder to one degree or another, mainly depressive. How many of them experience metamorphopsia is unknown exactly.

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Causes metamorphoses

Metamorphopsia is not a separate disease. This phenomenon of perception can be provoked by pathological changes in the organs of vision or diseases of the central nervous system.

Ophthalmological causes of the said optical illusion are related to diseases of the retina, which in one way or another affect the macula – the concentration of light-sensitive cones (receptors). The resulting distortions of what is seen are called receptor metamorphopsia. For example, in case of inflammation of the choroid, the inflammatory infiltrate can compress this area of the retina.

Refractive metamorphopsia occurs when there are disturbances in the refractive power of the optical system of the visual organs, for example, with astigmatism and high degrees of myopia.

The cause of image distortion may be diseases and injuries of the brain, intoxication psychoses, neuroses, affective disorders. In this case, patients, as a rule, have everything in order with their visual organs.

Any causes that lead to distortion of sensory sensations, assimilation of information, disruption of logical thinking, attention, memory, motivation can lead to disorders of visual perception.

Metamorphopsia can persist for a long time. The stability of the phenomenon indicates the seriousness and constancy of the cause that caused it.

Pathological distortion of reality can be a temporary phenomenon that occurs at any time of the day, however, it is often of a pre-drowsy nature, that is, a disturbance in perception is noted at the moment of going to sleep or waking up, and is also presented in dreams.

Short-term metamorphopsia may appear depending on the situation - arise after nervous tension, excitement, stress. In epileptics, they are often observed after attacks or precede them.

Patients usually feel the ephemeral nature of what is happening, alienation from it. Sometimes there is a feeling of duality of perception - the simultaneous existence of a correct and disturbed assessment of perceived objects.

Risk factors for the development of metamorphopsia remain unclear to this day and are determined after a thorough diagnosis of the patient who has come with complaints of symptoms that worry him. Distorted perception accompanies functional and organic visual disorders (initial stage of cataract, astigmatism, high myopia, choroiditis, retinal detachment); migraine with aura; vestibular disorders; organic pathologies of the occipital-parietal region of the cerebral cortex (tumors, injuries, strokes); focal epilepsy; schizophrenia; severe infectious intoxications occurring with damage to the central nervous system. Distorted perception is typical for people who abuse psychoactive substances.

Ephemeral short-term metamorphopsias are often encountered in the practice of borderline psychiatry in hysteria, neuroses, affective and reactive states (often in the symptom complex of depersonalization/derealization syndrome). Such patients usually do not show any visual impairment. Purely psychoneurological manifestations of distorted self- or worldview are also called Alice in Wonderland syndrome.

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Risk factors

Corresponding clinical manifestations often arise against the background of focal lesions of areas of the cerebral cortex responsible for the perception of the physical characteristics of objects and phenomena - neural activity changes locally, accelerates or slows down, which leads to distorted perception.

The impetus for the emergence of this phenomenon can be infection (inflammation of the retina or meninges); trauma - craniocerebral, intraocular; mental illness; substance abuse, stressful events, etc.

Modern research suggests that distortion of the shape and size of perceived objects is characteristic of lesions in the interparietal sulcus area of the brain, which plays a significant role in the synthesis of received sensory material.

The disturbance of the frontal lobes of the brain, which allow differentiation of objects in the foreground and background, as well as the occipital lobes, which participate in spatial orientation, are also considered. For example, increased neuronal activity in the frontal lobes of the brain is associated with incorrect perceptions that occur during migraine with aura.

The International Classification of Diseases classifies metamorphopsia as a class of eye diseases and treats it as a “subjective visual disorder”, however, in many cases, the incorrect perception of objects and phenomena is caused by purely neurological reasons.

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Pathogenesis

The pathogenesis of metamorphopsia is, accordingly, very diverse and has not been studied in detail. Visual perception of an object can be distorted due to pathology of the light-sensitive receptors of the macula, refractive disorders, i.e. caused by ophthalmological reasons. In this case, the human nervous system suffers from inconveniences associated with dysfunction of the visual organs. In the absence of their damage, this pathology is considered a disruption of the central mechanisms of the cerebral apparatus.

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Symptoms metamorphoses

The first signs of the disorder appear unexpectedly and rarely leave the patient indifferent to the metamorphoses being experienced. Especially if the condition does not let go. Distorted perception of parts of one's own body or objects of the surrounding world, less often - both, immediately causes, at a minimum, bewilderment, and more often - thoughts of madness.

Short-term metamorphopsias are easier to experience, but long-term disorders that do not go away for several hours or days can cause the patient to become completely disoriented, panic, and lose the ability to control their behavior.

The complaints of patients look something like this: “my head has become so big that it doesn’t fit in the room”; “objects around me suddenly become small, as if for Lilliputians” or “the walls of the closet have become wavy”.

Distortions may concern only parts of the individual's body - autometamorphopsia; objects surrounding it - allometamorphopsia. They may be perceived as disproportionately large - macropsia or very small - micropsia. Distortion of the size of objects, discrepancy in the size of their parts, various deformations, bends, apparent change in texture, asymmetry have the collective name of dysmegalopsia. It may be a symptom of accommodation paralysis, macular dystrophy, and also mental disorders (one of the main manifestations of Alice syndrome).

Metaphoropsia can be expressed in the distortion of the distance to the observed object, the shape and size of which are perceived correctly. It seems to the patient to be located much closer or further than it actually is. This form of distortion is called porropsia. It can indicate both retinal degeneration and damage to the parietal and occipital lobes of the cerebral cortex.

Often, patients perceive objects as larger and closer than they actually are (macroteleopsy) or smaller and more distant (microteleopsy).

If a single object literally multiplies before the eyes of the patient, such a disorder is called polyopia. It can be a symptom of incipient cataracts, keratoconus, and other ophthalmological pathologies affecting the cornea or lens.

In people with normal vision, polyopia can be observed in hysterical disorders.

Focal lesions of the cerebral cortex and focal epilepsy often manifest as a spatial rotation syndrome. Objects located on one side of the observer are perceived as being on the other. The rotation can be at different angles, most often at 180°, for example, objects or people walking in front are perceived as being behind. Cases of 90° rotation have also been described - for example, an object located in front of the observer is perceived as being to the right or left of him. Objects can also be rotated both vertically and horizontally.

Incorrect assessment of the location of an object is called optical allesthesia. The patient may complain that when looking at his reflection, he feels it behind him, or the person walking next to him feels like he has gone far ahead or is significantly behind. Allesthesia can be olfactory (the patient cannot correctly determine the location of the source of the smell) or acoustic (the source of the sound).

The symptoms are very diverse, sometimes the same patient has a distorted perception of both himself (auto-) and the surrounding world (allo-). This condition is referred to as ambivalent metamorphopsia.

There is also chronopsia – a distorted perception of time, a discrepancy in the projection of certain events onto periods of time.

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Complications and consequences

Distortion of habitual ideas about the environment and oneself, especially long-term and persistent, causes significant discomfort and can lead to complete disorientation.

For example, incorrect assessment of the distance to objects, the direction of their movement leads to difficulties in performing such simple actions as sitting on a chair or putting something on a table. Crossing the roadway of the street becomes life-threatening for people with spatial metamorphopsia.

In addition, such a symptom as a distorted perception of one's body and/or the surrounding world may indicate that the patient has serious mental illnesses - schizophrenia, epilepsy, brain tumors. Metamorphopsia in patients with diabetes may indicate the development of serious complications associated with damage to the blood vessels of the retina. Sometimes it is the distortion of vision that occurs in the early stages of the disease that allows for timely diagnosis of diabetes.

Any, even short-term manifestations of metamorphopsia should not be ignored, because no matter what they are caused by, they are evidence of trouble.

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Diagnostics metamorphoses

The basis for the examination is the patient's complaints. If ophthalmological causes of distortion of visual images can be identified using special tables and tests, in particular, the Amsler test is used, hardware methods - refractometry, ophthalmometry, ophthalmoscopy, ultrasound of the eyeball and others, that is, patients complain specifically about distorted vision of objects.

In cases of psychosensory disorder, patients often experience abnormal sensations even with their eyes closed. In most cases, metamorphopsia is combined with other psychopathological symptoms - anxiety, inability to perform purposeful actions, movements, reasoning, and the occurrence of panic attacks.

To identify the underlying disease, various laboratory (analysis of the contents of a spinal puncture) and instrumental methods (EEG, computed tomography and magnetic resonance imaging) studies are used, depending on the suspected diagnosis.

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Differential diagnosis

Differential diagnostics are performed to establish the cause of this disorder. Autometamorphopsia in focal epilepsy or schizophrenia is differentiated from conditions that arise as a consequence of severe infectious diseases, cerebral vascular pathologies, intracranial tumors or head injuries. Metamorphopsia caused by chronic or acute alcohol (drug) intoxication is differentiated.

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Treatment metamorphoses

Therapy for metamorphopsia is determined by the nature of the underlying disease. Medicines that would help all at once get rid of metamorphopsia have not yet been invented. The effectiveness of treatment depends on the correct determination of the primary source of distorted perception.

Depending on the diagnostic results, different treatment methods are used. For inflammatory diseases of the vascular membrane of the eye and retina, drug therapy is prescribed depending on the identified pathogen - antibacterial, antiviral, antiparasitic, anti-inflammatory. Eye drops are used locally, systemic therapy and drug electrophoresis may be prescribed.

In diabetic retinopathy, the main focus is on stabilizing blood glucose levels.

Refractive errors are corrected by selecting appropriate optics. If necessary, surgical interventions are performed, cryo- and laser therapy is used.

Degenerative age-related diseases are also quite successfully corrected with the help of surgery.

The main drugs for treating schizophrenia are neuroleptics. Patients usually take them throughout their lives, which allows them to maintain their quality of life at a practically normal level.

Epileptics are prescribed courses of anticonvulsant therapy, and brain tumors are removed surgically.

Patients with vegetative-vascular dystonia, migraines, meningoencephalitis can be helped by analgesics, with affective disorders - sedatives of plant origin or antidepressants. In case of cerebral circulation disorders, hypoxia, consequences of intoxication and trauma, drugs with nootropic activity are used.

Psychocorrection is used in combination with drug therapy - training courses with a psychologist are conducted in the form of group sessions or according to an individual program. They are aimed at restoring impaired thinking functions.

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Prevention

Metamorphopsia can be prevented in practically healthy people by following general recommendations for strengthening your own body. An active lifestyle and proper nutrition will help avoid infectious diseases or endure them in a mild form.

Optimization of the work and rest regime will promote rational distribution of physical, mental, visual load, increase stress resistance. Positivism and optimistic attitude will help to avoid psychotraumatic situations.

Eradicating bad habits guarantees the absence of alcohol and/or drug psychosis. Even the likelihood of injuries, severe infections and tumors, as well as migraines and affective states in fans of a healthy lifestyle is much lower.

For people with chronic diseases, the main preventive measure is regular medical supervision, timely diagnosis and conscientious implementation of all recommendations of the attending physician.

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Forecast

Modern ophthalmology has a sufficient arsenal of tools to help patients with distorted perception of visual objects.

Psychosensory disorders can also be corrected. Even in the presence of mental illnesses, drug-compensated states of long-term remission occur in the vast majority of cases. However, the final prognosis for recovery depends on the cause of metamorphopsia.

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