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Distribution of rods and cones along a line passing through the fovea and the blind spot of a human eye [1]. A blind spot, scotoma, is an obscuration of the visual field.A particular blind spot known as the physiological blind spot, "blind point", or punctum caecum in medical literature, is the place in the visual field that corresponds to the lack of light-detecting photoreceptor cells on the ...
A scotoma may include and enlarge the normal blind spot. Even a small scotoma that happens to affect central or macular vision will produce a severe visual disability, whereas a large scotoma in the more peripheral part of a visual field may go unnoticed by the bearer because of the normal reduced optical resolution in the peripheral visual field.
Scintillating scotoma is a common visual aura that was first described by 19th-century physician Hubert Airy (1838–1903). 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. [4]
The visual field is measured by perimetry.This may be kinetic, where spots of light are shown on the white interior of a half sphere and slowly moved inwards until the observer sees them, or static, where the light spots are flashed at varying intensities at fixed locations in the sphere until detected by the subject.
For example, naturally in monocular vision at the physiological blind spot, the percept is not a hole in the visual field, but the content is “filled-in” based on information from the surrounding visual field. When a textured stimulus is presented centered on but extending beyond the region of the blind spot, a continuous texture is perceived.
This is a dangerous sign, indicative of a brain tumor, CNS inflammation or idiopathic intracranial hypertension (IIH) that may become manifest in the near future. Thus, a biopsy is routinely performed prior to the treatment in the initial stages of papilledema to detect whether a brain tumor is present. If detected, laser treatment, radiation ...
Blind spot (vision), also known as the physiological blind spot, the specific scotoma in the visual field that corresponds to the lack of light-detecting photoreceptor cells on the optic disc Optic disc , also known as the anatomical blind spot, the specific region of the retina where the optic nerve and blood vessels pass through to connect to ...
Diagnostic techniques like ophthalmoscopy, visual field test, optical coherence tomography, fluorescein angiography, multifocal electroretinography and electrophysiology may be used in diagnosing AIBSE syndrome. [2] Subjective measurement of blind spot enlargement is done using visual field testing. [4]