Micropsia is a condition affecting human visual perception in which objects are perceived to be smaller than they actually are. Micropsia can be caused by optical factors (such as wearing glasses), by distortion of images in the eye (such as optically, via swelling of the cornea or from changes in the shape of the retina such as from retinal edema, macular degeneration, or central serous retinopathy), by changes in the brain (such as from traumatic brain injury, epilepsy, migraines, prescription drugs, and illicit drugs), and from psychological factors. Dissociative phenomena are linked with micropsia, which may be the result of brain-lateralization disturbance.Micropsia is also commonly reported when the eyes are fixating at (convergence), or focusing at (accommodation), a distance closer than that of the object in accord with Emmerts law. Specific types of micropsia include hemimicropsia, a form of micropsia that is localized to one half of the visual field and can be caused by brain lesions in one of the cerebral hemispheres. Related visual distortion conditions include macropsia, a less common condition with the reverse effect, and Alice in Wonderland syndrome, a condition that has symptoms that can include both micropsia and macropsia. Signs and symptoms
Micropsia causes affected individuals to perceive objects as being smaller or more distant than they actually are.The majority of individuals with micropsia are aware that their perceptions do not mimic reality. Many can imagine the actual sizes of objects and distances between objects.
Treatment
Treatment varies for micropsia due to the large number of different causes for the condition.Treatments involving the occlusion of one eye and the use of a prism fitted over an eyeglass lens have both been shown to provide relief from micropsia.Micropsia that is induced by macular degeneration can be treated in several ways. A study called AREDS (age-related eye disease study) determined that taking dietary supplements containing high-dose antioxidants and zinc produced significant benefits with regard to disease progression. This study was the first ever to prove that dietary supplements can alter the natural progression and complications of a disease state. Laser treatments also look promising but are still in clinical stages. Epidemiology
Episodes of micropsia or macropsia occur in 9% of adolescents.10-35% of those with migraines experience auras, with 88% of these patients experiencing both visual auras (which include micropsia) and neurological auras.Micropsia seems to be slightly more common in boys than in girls among children who experience migraines.Approximately 80% of temporal lobe seizures produce auras that may lead to micropsia or macropsia. They are a common feature of simple partial seizures and usually precede complex partial seizures of temporal lobe origin.Central Serous Chorioretinopathy (CSCR) which can produce micropsia predominantly affects persons between the ages of 20 and 50. Women appear to be affected more than men by a factor of almost 3 to 1.