![]() However, evidence from more recent case studies did not support this theory as cases where the polyopic images were thought not to correspond with the degree of involuntary eye movement. This leads to the creation of new retinal and cortical regions that code for a false macula which is the underlying cause of the duplicated images. The initial theory proposed by Bender explains the duplicated images as a result of the instability of fixation during small, involuntary eye movements. Multiple theories have been postulated for the underlying mechanisms. A more recent case reports cerebral polyopia in a patient with a left fronto-parietal infarction sparing the occipital lobe and with no visual field deficit Most of the cases of cerebral polyopia have been described to be associated with visual field deficits and are thought to localize to the occipital lobe. Cerebral polyopia may result from a variety of cerebral injuries including but not limited to trauma, ischemic stroke, migraine, encephalitis, seizures, tumors, and multiple sclerosis. However, most instances of polyopia are associated with a lesion in the occipital lobe, more specifically the visual association cortex, or following occipital lobe epilepsy. The mechanisms underlying the disease are uncertain and continue to be investigated. The extreme rarity of the disease, the similarities to other more common visual disturbances, and the variations in the presentation have hindered the ability to properly understand the etiology of the disease as well as find appropriate treatments. ![]() Since then, reports of cerebral polyopia have remained limited. Bender’s work further described polyopia through the documentation of four individuals with the disease. Giovanni Mingazzini, who described the disease in relation to an occipital lobe injury. Additional differences between patients include but are not limited to the following the number of duplicated images which can reach up to hundreds of images, the distance between the target stimulus and the duplicated images, the size and colour of the duplicated images compared to the original, and duration of time in which the duplicated images remains.Ĭerebral polyopia was first reported in 1908 by Dr. When only two images are observed, the original and the duplicate, the phenomenon is labeled as cerebral diplopia, a subtype of cerebral polyopia. The presentation of the duplicated image(s) varies between patients. Additionally, it does not improve with pinhole distinguishing it from ocular abnormalities such as cataract and refractive error. In other words, there is persistence of two or more duplicated images even after the stimulus is removed.Ĭerebral polyopia, which is an extremely rare phenomenon, occurs even with monocular viewing of each eye, distinguishing it from strabismic diplopia, but disappears when the stimulus is removed. There are three different types of visual perseveration which can occur in isolation or in combination llusory visual spread in which the visual image is not contained within its spacial boundary, palinopsia in which there is perseveration of a visual image in time, and Cerebral Polyopia, also known as Cerebral Diplopia, in which there is perseveration of a visual image in space, resulting in the perception of multiple images from a single visual stimulus. ![]() Visual perseveration is a positive visual phenomenon in which the visual image either recurs, persists, or is duplicated. ![]()
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