Rainbow kaleidoscope definition11/8/2023 Other terms for the condition include flittering scotoma, fortification figure, fortification of Vauban, geometrical spectrum, herringbone, Norman arch, teichopsia, and teleopsia. The British physician Hubert Airy coined the term scintillating scotoma for it by 1870 he derived it from the Latin scintilla "spark" and the Ancient Greek skotos "darkness". The British physician John Fothergill described the condition in the 18th century and called it fortification spectrum. Typically the scotoma resolves spontaneously within the stated time frame, leaving no subsequent symptoms, though some report fatigue, nausea, and dizziness as sequelae. For many sufferers, scintillating scotoma is first experienced as a prodrome to migraine, then without migraine later in life. Symptoms typically appear gradually over 5 to 20 minutes and generally last less than 60 minutes, leading to the headache in classic migraine with aura, or resolving without consequence in acephalgic migraine. The study did not find a link between late-life onset scintillating scotoma and stroke. The Framingham Heart Study, published in 1998, surveyed 5,070 people between ages 30 and 62 and found that scintillating scotomas without other symptoms occurred in 1.23% of the group. While monosodium glutamate (MSG) is frequently reported as a dietary trigger, other scientific studies do not support this claim. People with migraines often self-report triggers for migraines involving stress or foods, or bright lights. Migraines, in turn, may be caused by genetic influences and hormones. Scintillating scotomas are most commonly caused by cortical spreading depression, a pattern of changes in the behavior of nerves in the brain during a migraine. Sufferers can keep a diary of dates on which the episodes occur to show to their physician, plus a small sketch of the anomaly, which may vary between episodes.Ī depiction of a scintillating scotoma that was almost spiral-shaped, with distortion of shapes but otherwise melting into the background similarly to the physiological blind spot. Normal central vision may return several minutes before the scotoma disappears from peripheral vision. It may be difficult to read and dangerous to drive a vehicle while the scotoma is present. This is a different disease from retinal migraine, which is monocular (only one eye). The visual anomaly results from abnormal functioning of portions of the occipital cortex at the back of the brain, not in the eyes nor any component thereof, such as the retinas. Others describe patterns within the arc as resembling herringbone or Widmanstätten patterns. It also can resemble the dazzle camouflage patterns used on ships in World War I. teichopsia, from Greek τεῖχος, town wall), because of its resemblance to the fortifications of a castle or fort seen from above. An arc of light may gradually enlarge, become more obvious, and may take the form of a definite zigzag pattern, sometimes called a fortification spectrum (i.e. Some describe seeing one or more shimmering arcs of white or colored flashing lights. In teichopsia, migraine sufferers see patterns in the shape of the walls of a star fort.Īs the scotoma area expands, some people perceive only a bright flickering area that obstructs normal vision, while others describe seeing various patterns. It may occur as an isolated symptom without headache in acephalgic migraine. The scotoma area may expand to occupy one half of the visual area of one eye, or it may be bilateral. 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. It then gradually expands outward from the initial spot. The affected area flickers but is not dark. It typically affects both eyes, as it is not a problem specific to one eye. Many variations occur, but scintillating scotoma usually begins as a spot of flickering light near or in the center of the visual field, which prevents vision within the scotoma area. Signs and symptoms An artist's depiction of a scintillating scotoma with a bilateral arc. It is often confused with retinal migraine, which originates in the eyeball or socket. Originating from the brain, it may precede a migraine headache, but can also occur acephalgically (without headache), also known as visual migraine or migraine aura. Scintillating scotoma is a common visual aura that was first described by 19th-century physician Hubert Airy (1838–1903). Persistent aura without infarction, Retinal migraineĪrtist's depiction of a Scintillating scotoma, exhibiting a flashing visual pattern similar to Dazzle camouflage used during WWI. Example of a scintillating scotoma, as may be caused by cortical spreading depressionĪura in vision, nausea, dizziness, brain fog
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