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Illusory palinopsia is often worse with high stimulus intensity and contrast ratio in a dark adapted state.Multiple types of illusory palinopsia often co-exist in a patient and occur with other diffuse, persistent illusory symptoms such as halos around objects, dysmetropsia (micropsia, macropsia, pelopsia, or teleopsia), Alice in Wonderland Syndrome, visual snow, and oscillopsia.
Palinopsia (Greek: palin for "again" and opsia for "seeing") is the persistent recurrence of a visual image after the stimulus has been removed. [1] Palinopsia is not a diagnosis; it is a diverse group of pathological visual symptoms with a wide variety of causes. Visual perseveration is synonymous with palinopsia. [dubious – discuss]
Closed-eye hallucinations and closed-eye visualizations (CEV) are hallucinations that occur when one's eyes are closed or when one is in a darkened room. They should not be confused with phosphenes, perceived light and shapes when pressure is applied to the eye's retina, or some other non-visual external cause stimulates the eye.
Visual snow is a phenomenon where a person perceives visual disturbances, such as fine graininess or "static," in their field of vision. This can occur in low-light conditions, in the dark, or when the visual system amplifies light perception.
Typical symptoms of the disorder include halos or auras surrounding objects, trails following objects in motion, difficulty distinguishing between colors, apparent shifts in the hue of a given item, the illusion of movement in a static setting, visual snow, distortions in the dimensions of a perceived object, intensified hypnagogic and hypnopompic hallucinations, monocular double vision ...
In teichopsia, migraine sufferers may see patterns that look like the shape of the walls of a star fort. As the scotoma area expands, some people perceive only a bright flickering area that obstructs normal vision, while others describe seeing various patterns. Some describe seeing one or more shimmering arcs of white or colored flashing lights.
The appearance of visual complaints such as halos, glare and monocular diplopia after corneal refractive surgery has long been correlated with the induction of optical aberrations. Several mechanisms may explain the increase in the amount of higher-order aberrations with conventional excimer laser refractive procedures: a change in corneal ...
Cyanopsia is a rare visual phenomenon characterized by a blue tint to vision. Most commonly associated with cataract surgery and certain medications, such as sildenafil , cyanopsia is typically a temporary side effect rather than a standalone disease.