What happens if cut optic chiasm
Definition NCI The lateral of a pair of small oval masses that protrude slightly from the posteroinferior aspect of the thalamus; commonly considered a part of the metathalamus. Definition CSP mass composed of lateral geniculate nucleus, located lateral to the medial geniculate body, and serving as the thalamic center for the visual system. Ontology: Optic tract structure C Definition FMA Nerve trunk which is continuous with the optic chiasm and the lateral geniculate nucleus.
Definition PSY Portion of the optic pathway that extends posteriorly from the optic chiasm in two nerve fiber bundles to synapse near the superior colliculi and in the lateral geniculate body of the thalamus. Definition CSP bundle of nerve fibers of the visual system from the optic chiasm to the lateral geniculate nucleus, with some fibers synapsing in the midbrain for reflex connections.
Ontology: Structure of optic radiation C Ontology: Visual pathway structure C Ontology: Visual system structure C Related Topics in Anatomy. Ophthalmology Chapters. Ophthalmology - Anatomy Pages. Back Links pages that link to this page. Search other sites for 'Neurologic Anatomy of the Eye'. Nerve trunk which is continuous with right and left optic nerves and right and left optic tracts. An anatomic structure formed by the crossing of the two optic nerves under the hypothalamus.
An anatomy term for an X-shaped crossing for example, of nerves or tendons. The place in the brain where some of the optic nerve fibers coming from one eye cross optic nerve fibers from the other eye. Damage to an optic nerve or damage to its pathways to the brain results in loss of vision.
At a structure in the brain called the optic chiasm, each optic nerve splits, and half of its fibers cross over to the other side. Because of this anatomic arrangement, damage along the optic nerve pathway causes specific patterns of vision loss. By understanding the pattern of vision loss, a doctor can often determine where the problem is in the pathway. Nerve signals travel along the optic nerve from each eye.
The two optic nerves meet at the optic chiasm. There, the optic nerve from each eye divides, and half of the nerve fibers from each side cross to the other side. People that suffer from a one-sided defect sometimes do not notice it until one eye is covered.
This is because, when both eyes are open, the overlapping visual fields of each eye will mask the defect. If the disease affects at the chiasm, then the temporal visual fields will be affected in both eyes and anything further back in the brain behind the chiasm both eyes' visual field will also be affected but will be affected on the same side.
If the disease affects the optic tract after the chiasm, the person will have a defect in their vision in both eyes, but the defect will alter the same half of the visual field. Sign up for our Health Tip of the Day newsletter, and receive daily tips that will help you live your healthiest life.
Larsson M. Front Zool. Gala F. Magnetic resonance imaging of optic nerve. Indian J Radiol Imaging. Progressive loss of vision caused by asymptomatic pituitary macroadenoma: role of OCT. Int Med Case Rep J. National Library of Medicine. Pituitary tumor. Updated May 6, Your Privacy Rights. The red part of the bar will project to the nasal part of your left retina and the temporal lateral part of your right retina.
The blue part of the bar will project to the nasal part of your right retina and the temportal lateral part of your left retina. Right and left visual information cross to opposite sides of the brain. This crossover occurs in the optic chiasm. After the optic chiasm, information about the right visual field blue is on the left side of the brain, and information about the left visual field red is on the right side.
The pathways stay this way all the way up to the visual cortex.
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