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Optic nerve

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The optic nerve, also known as cranial nerve II, is a paired nerve that transmits visual information from the retina to the brain. [1]

56 relations: Accommodation reflex, Aneurysm, Anterior ischemic optic neuropathy, Arachnoid mater, Axon, Bitemporal hemianopsia, Blind spot (vision), Brain, Central nervous system, Cranial nerves, Cuneus, Diencephalon, Dura mater, Endoneurium, Fovea centralis, Glaucoma, Guillain–Barré syndrome, Lateral geniculate nucleus, Leber's hereditary optic neuropathy, Meninges, Multiple sclerosis, Nerve, Neuro-ophthalmology, Neuroglia, Occipital lobe, Oligodendrocyte, Ophthalmic artery, Ophthalmology, Optic canal, Optic chiasm, Optic disc, Optic nerve hypoplasia, Optic neuritis, Optic neuropathy, Optic radiation, Optic stalk, Optic tract, Optometry, Orbit (anatomy), Peripheral nervous system, Peripheral neuropathy, Peripheral vision, Photoreceptor cell, Pia mater, Pituitary adenoma, Pretectal area, Pupillary reflex, Retina, Retinal ganglion cell, Schwann cell, ..., Superior colliculus, Suprachiasmatic nucleus, Visual cortex, Visual field, Visual perception, Visual system. Expand index (6 more) »

Accommodation reflex

The accommodation reflex (or accommodation-convergence reflex) is a reflex action of the eye, in response to focusing on a near object, then looking at a distant object (and vice versa), comprising coordinated changes in vergence, lens shape and pupil size (accommodation).

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An aneurysm is a localized, abnormal, weak spot on a blood vessel wall that causes an outward bulging, likened to a bubble or balloon.

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Anterior ischemic optic neuropathy

Anterior ischemic optic neuropathy (AION) is a medical condition involving loss of vision caused by damage to the optic nerve as a result of insufficient blood supply (ischemia).

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Arachnoid mater

The arachnoid mater is one of the three meninges, the protective membranes that cover the brain and spinal cord.

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An axon (from Greek ἄξων áxōn, axis) or nerve fiber, is a long, slender projection of a nerve cell, or neuron, that typically conducts electrical impulses known as action potentials, away from the nerve cell body.

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Bitemporal hemianopsia

Bitemporal hemianopsia, also known as bitemporal heteronymous hemianopsia or bitemporal hemianopia, is the medical description of a type of partial blindness where vision is missing in the outer half of both the right and left visual field.

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Blind spot (vision)

A blind spot, scotoma, is an obscurity of the visual field.

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The brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals.

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Central nervous system

The central nervous system (CNS) is the part of the nervous system consisting of the brain and spinal cord.

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Cranial nerves

Cranial nerves are the nerves that emerge directly from the brain (including the brainstem), in contrast to spinal nerves (which emerge from segments of the spinal cord).

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The '''cuneus''' (Latin for "wedge"; plural, cunei) is a smaller lobe in the occipital lobe of the brain.

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The diencephalon is a division of the forebrain (embryonic prosencephalon), and is situated between the telencephalon and the midbrain (embryonic mesencephalon).

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Dura mater

Dura mater, or dura, is a thick membrane made of dense irregular connective tissue that surrounds the brain and spinal cord.

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The endoneurium (also called endoneurial channel, endoneurial sheath, endoneurial tube, or Henle's sheath) a layer of delicate connective tissue around the myelin sheath of each myelinated nerve fiber.

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Fovea centralis

The fovea centralis is a small, central pit composed of closely packed cones in the eye.

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Glaucoma is a group of eye diseases which result in damage to the optic nerve and vision loss.

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Guillain–Barré syndrome

Guillain–Barré syndrome (GBS) is a rapid-onset muscle weakness caused by the immune system damaging the peripheral nervous system.

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Lateral geniculate nucleus

The lateral geniculate nucleus (LGN; also called the lateral geniculate body or lateral geniculate complex) is a relay center in the thalamus for the visual pathway.

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Leber's hereditary optic neuropathy

Leber's hereditary optic neuropathy (LHON) or Leber hereditary optic atrophy is a mitochondrially inherited (transmitted from mother to offspring) degeneration of retinal ganglion cells (RGCs) and their axons that leads to an acute or subacute loss of central vision; this affects predominantly young adult males.

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The meninges (singular: meninx, from membrane, adjectival: meningeal) are the three membranes that envelop the brain and spinal cord.

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Multiple sclerosis

Multiple sclerosis (MS) is a demyelinating disease in which the insulating covers of nerve cells in the brain and spinal cord are damaged.

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A nerve is an enclosed, cable-like bundle of axons (nerve fibers, the long and slender projections of neurons) in the peripheral nervous system.

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Neuro-ophthalmology is an academically-oriented subspecialty that merges the fields of neurology and ophthalmology, often dealing with complex systemic diseases that have manifestations in the visual system.

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Neuroglia, also called glial cells or simply glia, are non-neuronal cells in the central nervous system (brain and spinal cord) and the peripheral nervous system.

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Occipital lobe

The occipital lobe is one of the four major lobes of the cerebral cortex in the brain of mammals.

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Oligodendrocytes, or oligodendroglia,.

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Ophthalmic artery

The ophthalmic artery (OA) is the first branch of the internal carotid artery distal to the cavernous sinus.

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Ophthalmology is a branch of medicine and surgery (both methods are used) that deals with the anatomy, physiology and diseases of the eyeball and orbit.

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Optic canal

The optic foramen is the opening to the optic canal. The canal is located in the sphenoid bone; it is bounded medially by the body of the sphenoid and laterally by the lesser wing of the sphenoid. The superior surface of the sphenoid bone is bounded behind by a ridge, which forms the anterior border of a narrow, transverse groove, the chiasmatic groove (optic groove), above and behind which lies the optic chiasma; the groove ends on either side in the optic foramen, which transmits the optic nerve and ophthalmic artery (with accompanying sympathetic nerve fibres) into the orbital cavity. Compared to the optic nerve, the ophthalmic artery is located inferolaterally within the canal. The left and right optic canals are 25mm apart posteriorly and 30mm apart anteriorly. The canals themselves are funnel-shaped (narrowest anteriorly).

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Optic chiasm

The optic chiasm or optic chiasma (Greek χίασμα, "crossing", from the Greek χιάζω 'to mark with an X', after the Greek letter 'Χ', chi) is the part of the brain where the optic nerves partially cross.

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Optic disc

The optic disc or optic nerve head is the point of exit for ganglion cell axons leaving the eye.

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Optic nerve hypoplasia

Optic nerve hypoplasia (ONH) is a medical condition arising from the underdevelopment of the optic nerve(s).

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Optic neuritis

Optic neuritis is a demyelinating inflammation of the optic nerve.

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Optic neuropathy

Optic neuropathy is damage to the optic nerve from any cause.

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Optic radiation

The optic radiation (also known as the geniculocalcarine tract, the geniculostriate pathway, and posterior thalamic radiation) are axons from the neurons in the lateral geniculate nucleus to the primary visual cortex.

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Optic stalk

The optic vesicles project toward the sides of the head, and the peripheral part of each expands to form a hollow bulb, while the proximal part remains narrow and constitutes the optic stalk.

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Optic tract

The optic tract (from the Latin tractus opticus) is a part of the visual system in the brain.

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Optometry is a health care profession which involves examining the eyes and applicable visual systems for defects or abnormalities as well as the medical diagnosis and management of eye disease.

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Orbit (anatomy)

In anatomy, the orbit is the cavity or socket of the skull in which the eye and its appendages are situated.

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Peripheral nervous system

The peripheral nervous system (PNS) is one of the two components of the nervous system, the other part is the central nervous system (CNS).

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Peripheral neuropathy

Peripheral neuropathy (PN) is damage to or disease affecting nerves, which may impair sensation, movement, gland or organ function, or other aspects of health, depending on the type of nerve affected.

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Peripheral vision

Peripheral vision is a part of vision that occurs only on the side gaze.

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Photoreceptor cell

A photoreceptor cell is a specialized type of neuroepithelial cell found in the retina that is capable of visual phototransduction.

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Pia mater

Pia mater (or in, retrieved 2012-07-28.), often referred to as simply the pia, is the delicate innermost layer of the meninges, the membranes surrounding the brain and spinal cord.

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Pituitary adenoma

Pituitary adenomas are tumors that occur in the pituitary gland.

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Pretectal area

The pretectal area, or pretectum, is a midbrain structure composed of seven nuclei and comprises part of the subcortical visual system.

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Pupillary reflex

Pupillary reflex refers to one of the reflexes associated with pupillary function.

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The retina is the innermost, light-sensitive "coat", or layer, of shell tissue of the eye of most vertebrates and some molluscs.

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Retinal ganglion cell

A retinal ganglion cell (RGC) is a type of neuron located near the inner surface (the ganglion cell layer) of the retina of the eye.

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Schwann cell

Schwann cells (named after physiologist Theodor Schwann) or neurolemmocytes are the principal glia of the peripheral nervous system (PNS).

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Superior colliculus

The superior colliculus (Latin, upper hill) is a paired structure of the mammalian midbrain.

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Suprachiasmatic nucleus

The suprachiasmatic nucleus or nuclei (SCN) is a tiny region of the brain in the hypothalamus, situated directly above the optic chiasm.

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Visual cortex

The visual cortex of the brain is a part of the cerebral cortex that processes visual information.

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Visual field

The visual field is the "spatial array of visual sensations available to observation in introspectionist psychological experiments".

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Visual perception

Visual perception is the ability to interpret the surrounding environment using light in the visible spectrum reflected by the objects in the environment.

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Visual system

The visual system is the part of the central nervous system which gives organisms the ability to process visual detail, as well as enabling the formation of several non-image photo response functions.

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2nd cranial nerve, CN II, Cranial nerve 2, Cranial nerve II, II cranial nerve, Nervus opticus, Optic (II) nerve, Optic nerve disease, Optic nerve diseases, Optic nerve injuries, Optic nerve neoplasms, Optic nerves, Optical nerve, Second cranial nerve.


[1] https://en.wikipedia.org/wiki/Optic_nerve

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