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It is light-sensitive and communicates visual messages to the brain. If the retina detaches, it moves and shifts from its normal position. This can cause photopsia, but can also cause permanent vision loss. Medical attention is needed to prevent vision loss. Procedures may include laser treatment, freezing, or surgery.
Moore's lightning streaks are lightning type streaks (seen to the temporal side) due to sudden head or eye movement in the dark. They are generally caused by shock waves in the vitreous humor hitting the retina or traction on the retina from fibers in the vitreous humor.
Flash blindness is an either temporary or permanent visual impairment during and following exposure of a varying length of time to a light flash of extremely high intensity, such as a nuclear explosion, flash photograph, lightning strike, or extremely bright light, i.e. a searchlight, laser pointer, landing lights or ultraviolet light. [1]
Flashes of light in vision ; Experiencing a "dark curtain" or shadow moving from the peripheral vision toward the central vision; Sudden blurred vision; Rarely, a retinal detachment may be caused by atrophic retinal holes, in which case symptoms such as floaters or flashes of light may not occur. [9] [10]
Vision remains normal beyond the borders of the expanding scotoma(s), with objects melting into the scotoma area background similarly to the physiological blind spot, which means that objects may be seen better by not looking directly at them in the early stages when the spot is in or near the center. The scotoma area may expand to occupy one ...
Apollo 17 astronaut Ron Evans wearing the ALFMED light-flash detector during the outbound flight from Earth During the Apollo 16 and Apollo 17 transits, astronauts conducted the Apollo Light Flash Moving Emulsion Detector (ALFMED) experiment where an astronaut wore a helmet designed to capture the tracks of cosmic ray particles to determine if ...
Magnetophosphenes are flashes of light that are seen when one is subjected to a changing magnetic field such as when in an MRI. This changing field causes current within the retina or visual cortex resulting in the illusion of light. [1] In one series, 8 out of 1023 people having an MRI experienced flashing lights. [2]
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.