
	Where results make sense

Topic: Optic tract

Related Topics

Persian Empire

Tammin Sursok

Speed of sound

Lester Young

List of Australians

In the News (Thu 17 Dec 09)

Northern Trust

Marvin Harrison

Peter Chernin

Gary Locke

Match Play

Penelope Cruz

Mickey Rourke

AR Rahman

Danny Boyle

Hugh Jackman

	Optic nerve - Wikipedia, the free encyclopedia
		The optic nerve is the second of twelve paired cranial nerves but is considered to be part of the central nervous system as it is derived from an outpouching of the diencephalon during embryonic development.
		Similarly, the optic nerve is ensheathed in all three meningeal layers (dura, arachnoid, and pia mater) rather than the epineurium, perineurium, and endoneurium found in peripheral nerves.
		The optic nerve component lengths are 1 mm in the globe, 25 mm in the orbit, 9 mm in the optic canal and 16 mm in the cranial space before joining the optic chiasm.
	en.wikipedia.org /wiki/Optic_nerve (921 words)

	IX. Neurology. 5b. The Optic Nerve. Gray, Henry. 1918. Anatomy of the Human Body.
		A few fibers of the optic nerve, of small caliber, pass from the primary centers to the retina and are supposed to govern chemical changes in the retina and also the movements of some of its elements (pigment cells and cones).
		The optic nerve is peculiar in that its fibers and ganglion cells are probably third in the series of neurons from the receptors to the brain.
		The crossed fibers of the optic nerve tend to occupy the medial side of the nerve and the uncrossed fibers the lateral side.
	www.bartleby.com /107/197.html (893 words)

	The Optic Nerve
		The optic nerve (also known as cranial nerve II) is a continuation of the axons of the ganglion cells in the retina.
		Optic neuropathy is divided into anterior, which causes a pale edema of the optic disk, and posterior, in which the optic disk is not swollen and the abnormality occurs between the eyeball and the optic chiasm.
		Ischemic anterior optic neuropathy usually causes a loss of vision that may be sudden or occur over several days; whereas, ischemic posterior optic neuropathy is uncommon, and the diagnosis depends largely upon exclusion of other causes, chiefly stroke and brain tumor.
	www.tedmontgomery.com /the_eye/optcnrve.html (1666 words)

	Webvision: Regeneration in the Goldfish Visual System
		In the goldfish, injury of the optic nerve induces an anabolic response in the ganglion cells that is the prelude to the regenerative response.
		And as is the case in the injured optic nerve, regenerating axons in the optic tract and spinal cord use phagocytic cells, not astrocytes, as scaffolding to traverse the lesion.
		On the contrary, both at the edge of the proximal nerve, and throughout the degenerating distal nerve, the disrupted fascicular pattern of the optic nerve is gradually restored, as the regenerating axons encounter the awaiting astrocytes, in a recapitulation of events occurring in normal development and growth of the fish optic nerve (cf.
	webvision.med.utah.edu /Nona.html (10718 words)

	Ocular Pathology Study Guide: What are the pathways of the cranial nerves?
		In the optic chiasm, the nerves from the medial half of each retina cross to enter the opposite optic tract, while the nerves from the lateral half of each retina pass into the optic tract of the same side.
		The optic tract is attached to the tuber cinereum and lamina terminalis and also to the cerebral peduncle as it crosses obliquely over its under surface.
		Voluntary impulses from the cerebral cortex are conveyed by terminals and collaterals of the pyramidal tract of the opposite side, indirectly, that is with the interpolation of a connecting neuron, to the facial nucleus.
	www.medrounds.org /ocular-pathology-study-guide/2006/03/what-are-pathways-of-cranial-nerves.html (2935 words)

	Optic Pathway Glioma - My Child Has - Children's Hospital Boston
		An optic pathway glioma is a tumor arising from a specific type of glial cell (supportive tissue of the brain) known as an astrocyte.
		Optic pathway gliomas are astrocytomas that arise in or around the optic pathway, i.e., the optic nerve, the optic chiasm or the optic radiations.
		NF-I is present in 70 percent of children with a glioma isolated to the optic nerve, and in 15-20 percent of children with a glioma of the optic chiasm or optic radiations.
	www.childrenshospital.org /az/Site1386/mainpageS1386P0.html (1264 words)

	Age-related fiber order in the optic tract of the ferret. (Site not responding. Last check: 2007-10-31)
		The unlabeled zones were seen in the tracts of animals having unlabeled regions in the periphery of the retina.
		Some irregularities in the layered arrangement of the tract are described, and the fiber order in the tract is contrasted with that in the optic nerve behind the eye.
		Between the retina and the optic tract, a sorting of fibers occurs not only in terms of the pattern of decussation, but also in terms of fiber age.
	www.arclab.org /medlineupdates/abstract_3840527.html (289 words)

	orbital_tumors
		Optic nerve gliomas are rare tumors comprising 1% of all intracranial tumors; but 10-15% of all supratentorial tumors in the pediatric population.
		Occasionally, a glioma from the optic tract or the anterior third ventricle region may involve the chiasma and the optic nerve secondarily.
		Unfortunately posteriorly located tumors are the most common form of optic nerve gliomas (60%) and it is often difficult to determine the actual origin of the tumor as they are frequently large and involve both the chiasm and the hypothalamus.
	www.thamburaj.com /optic_glioma.htm (1062 words)

	Diagnostic and Interventional Radiology
		This is due to the increase in the lipid/water ratio as triggered by the lipids that were released from the degraded myelin sheaths of the degenerated axons of the pyramidal tracts.
		Another explanation for the mild decrease of perfusion in the occipital cortex might be the decrease in the impulses arriving at the cortex from the optic tracts (transsynaptic inhibition).
		Ischemic lesions of the occipital cortex and optic radiations: positron emission tomography.
	www.dirjournal.org /text.php3?id=6 (1732 words)

	Optic Pathway Gliomas - MEDSTUDENTS - Neurosurgery (Site not responding. Last check: 2007-10-31)
		Tumors may appear as fusiform enlargement of the optic nerve, with the secondary involvement of the chiasm, or may envelop primarily the chiasm and spread secondary to the optic nerve or into the hypothalamus.
		Optic pathway gliomas may occur in adults, and in that situation the tumors may have the characteristics of a highly malignant tumor that causes early loss of vision and inevitable leads to the patients death.
		Optic gliomas limited to the intraorbital or intracranial optic nerve that do not include the chiasm and are associated with loss of vision are resected.
	www.medstudents.com.br /neuroc/neuroc3.htm (939 words)

	OCS: An Explanation of Optic Glioma.
		Optic Nerve Glioma, which primarily arise from cells called astrocytes, are usually slow-growing, low-grade tumours of a type called juvenile pilocytic astrocytoma (JPA), but can sometimes present in a more aggressive form, such as anaplastic astrocytoma and primative neuroectodermal tumour (PNET).
		They may also affect the junction of the optic nerves called the "optic chiasm", and an area of the brain called the hypothalamus..
		Optic nerve gliomas often remain stable for long periods of time, and many doctors thus favour a wait-and-watch-closely approach rather than embarking on agressive therapy.
	www.orphancancer.org /SONGS/ongoverview.html (584 words)

	[No title] (Site not responding. Last check: 2007-10-31)
		The optic nerve originates from the bipolar cells of the retina which are connected to the specialized receptors in the retina (rod and cone cells).
		The optic nerve exits the back of the eye in the orbit and enters the optic canal and exits into the cranium.
		It enters the central nervous system at the optic chiasm (crossing) where the nerve fibers become the optic tract just prior to entering the brain.
	www.meddean.luc.edu /lumen/MedEd/GrossAnatomy/h_n/cn/cn1/cn2.htm (107 words)

	Optic nerve and visual system
		One optic tract thus carries fibres from the temporal ipsilateral retina and the nasal contralateral retina.
		optic tract fibres reaching the lateral geniculate bodies pass to the brainstem to control refraction (lens) and pupillary aperture.
		The upper retinae (lower visual fields) project in the optic radiation through the parietal lobes to the upper part of the visual cortex, and the lower retinae (upper fields) through the temporal lobes, beneath the parietal, to the lower visual cortex.
	www.depression-guide.com /optic-nerve.htm (600 words)

	Optic tract - Wikipedia, the free encyclopedia
		773 - The left optic nerve and the
		The right optic tract consists of temporal retinal fibers from the right eye and nasal retinal fibers from the left eye; conversely, the left optic tract consists of temporal retinal fibers from the left eye and nasal retinal fibers from the right eye.
		This page was last modified 23:44, 8 July 2006.
	en.wikipedia.org /wiki/Optic_tract (132 words)

	Retinal Ganglion Cell Axon Progression from the Optic Chiasm to Initiate Optic Tract Development Requires Cell ...
		optic chiasm is composed of disorganized RGC axons (Fig.
		GAP-43 immunoreactivity is present in the optic fiber layer (OFL), at the optic disk, and in the optic nerve (ON), consistent with the presence of this protein in RGC axons.
		of the optic chiasm on the surface of the ventral diencephalon
	www.jneurosci.org /cgi/content/full/18/15/5692 (10822 words)

	Flash visual evoked potential monitoring of optic tract...
		In previous reports, the proximity of the optic tract to the lesion target in the globus pallidus internus has resulted in the occurrence of visual field deficits in as much as 14% of patients.
		The proximity of the optic tract to the ablative target, the globus pallidus internus (GPi), accounts for the association of PVP with postoperative visual field deficits.
		The proximity of the pallidal lesion to the optic tract on postoperative imaging (Fig.
	www.c3.hu /~mavideg/jns/2-3-4.html (4050 words)

	v414pathways10.html
		As the optic tract approaches its termination in the LGB, the macular bundle emerges on the tract's super surface; the inferior fibers lie on the lateral side and the superior fibers on tract's medial side, as represented in the diagram.
		Towards the end of the optic tract macular fibers push to the tract's superior surface; the inferior fibers move laterally and superior fibers medially.
		En route to optic tract the TI fibers in question lie close to the lateral edge of the optic chiasm.
	www.indiana.edu /~pietsch/v414pathways10.html (2874 words)

	[No title]
		Because the optic nerve does not project directly to the brainstem, it is not a true cranial nerve -at least in mammals- although some fibers (via the optic tract) are received in the midbrain visual colliculi.
		From the lateral geniculate nucleus these visual fibers form the optic radiations which project predominantly to the striate cortex within the occipital lobe, and give off collaterals to the inferior temporal and superior parietal lobe where the upper and lower visual fields are also represented.
		Complete destruction of the optic tract or its terminal zones induces a homonymous hemianopsia to the left or right, whereas a partial injury may induce a quadratic homonymous defect: upper quadrant being associated with temporal lobe defects, and lower quadrant defects associated with the superior parietal lobe.
	brainmind.com /OpticNerve.html (375 words)

	MR Imaging Study of Edema-like Change along the Optic Tract in Patients with Pituitary Region Tumors -- Saeki et al. 24 ...
		MR Imaging Study of Edema-like Change along the Optic Tract in Patients with Pituitary Region Tumors -- Saeki et al.
		Edema-like changes (large arrows) are visible bilaterally along the optic tract and are more prominent on the left side of the brain (right side of the figure).
		Optic tracts are difficult to differentiate from edema-like changes.
	www.ajnr.org /cgi/content/full/24/3/336/F2 (286 words)

	Optic Neuritis Treatment and Predictions for Multiple Sclerosis
		The optic nerve is a relatively small part of the central nervous system that carries information from the retina of the eye to the optic chiasm.
		Optic neuritis can be silent or sufficient to cause blindness, it can be painful or painless.
		Not until the optic neuritis treatment trial, when patients were randomly assigned to IV steroids (Solumedrol or methylprednisolone) followed by oral steroids (prednisone), oral steroids alone, or no treatment was it clearly determined that ultimately, being treated with steroids during the acute phase did not apparently affect the long term vision outcome.
	www.loftusmd.com /Articles/MS/opticneuritis.html (597 words)

	Medical Dictionary: Optic tract - WrongDiagnosis.com
		Optic tract: the cranial nerve that serves the retina
		Optic tract : 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.
		A hierarchical classification of Optic tract: The following list attempts to classify Optic tract into categories where each line is subset of the next.
	www.wrongdiagnosis.com /medical/optic_tract.htm (192 words)

	Architecture of the Optic Chiasm and the Mechanisms That Sculpt Its Development -- Jeffery 81 (4): 1393 -- ...
		ON, optic nerve; OX, optic chiasm; OT, optic tract.
		Optic axons extend during maturation via the progressive development of their growth cones along the optic pathway.
		Optic nerve growth cones appear to advance at a rate of ~60-100 µm/h (26), but there is evidence that this rate of growth
	physrev.physiology.org /cgi/content/full/81/4/1393 (11941 words)

	Ischemic Neuropathy Optic
		The condition of vision loss is identified as Naion (non-arteritic ischemic optic neuropathy), a block in the optic nerve due to lack of blood flow.
		The sight loss results from non-arteritic ischemic optic neuropathy, a condition where blood flow is blocked to the optic nerve, according to the FDA.
		This condition, known as Naion (non arteritic ischemic optic neuropathy), occurs when blood flow to the optic nerve is blocked.
	ischemicneuropathyoptic.marsneuropathy.com /posteriorischemicopticneur... (740 words)

	Anophthalmia and Retinal Degeneration Associated with Stenosis of the Optic Foramen in Fischer 344 Rats -- Shibuya et ...
		The left optic nerve is missing with the vestigial right optic tract (arrow).
		The dysplastic sphenoid bone (arrow) is present on the left side, and the atrophic optic nerve is in the stenotic left canal.
		Boynton JR, Pheasant TR, Levine MR: Hypoplastic optic nerves studied with B-scan ultrasonography and axial tomography of the optic canals.
	www.vetpathology.org /cgi/content/full/37/3/264 (1847 words)

	AR Online » 16Back Issues » May 1999 » Glioblastoma multiforme (GBM)
		This case presents an unusual pattern of spread along the optic tract post-chiasmatically, with evidence of continued spread to the level of the chiasm (ﬁgures 2,3).
		The lack of optic atrophy (ﬁgure 1) is indicative of the rapid growth of this GBM.
		In particular, MR is superior in visualizing the intracanalicular portions of the optic nerve, chiasm, hypothalamus, and optic tract pathways due to elimination of bone artifacts and improved contrast enhancement resulting from subtle differences in fat content and hydration of neural tissue.
	www.appliedradiology.com /case/case.asp?Id=33&IssueID=16 (858 words)

	Optic chiasm enhancement associated with giant aneurysm and yttrium treated pituitary adenoma -- Gabriel et al. 75 (9): ...
		Optic chiasm enhancement associated with giant aneurysm and yttrium treated pituitary adenoma -- Gabriel et al.
		The chiasm and proximal right optic tract are of high signal on FLAIR (A) and enhance with gadolinium on T1 (B and C).
		MR imaging study of edema-like change along the optic tract in patients with pituitary region tumours.
	jnnp.bmjjournals.com /cgi/content/full/75/9/1343 (1285 words)

	Nikon MicroscopyU: Confocal Image Gallery - Optic Nerve Head (40x)
		This region, devoid of photoreceptive cells, is where optic nerve fibers of the retina converge to leave the eyeball -- everyone has one of these blind spots in each eye.
		Optic nerve fibers that emerge from the eye travel to the cortex to transmit visual images to the brain.
		The nerve fibers eventually become the optic tract and extend to reach the visual cortex in the occipital lobe at the rear of the brain.
	www.microscopyu.com /galleries/confocal/opticnervehead40x.html (343 words)

	THE MERCK MANUAL, Sec. 8, Ch. 101, Optic Nerve And Optic Pathway Disorders
		Optic nerve lesions cause visual disturbances restricted to the affected eye.
		Lesions in the optic tract, optic radiations, or cerebral cortex produce homonymous hemianopia, with loss of function in the right or left halves of both visual fields opposite the side affected.
		This, the most common type of hemianopia, is usually caused by a brain tumor or cerebrovascular accident.
	www.merck.com /pubs/mmanual/section8/chapter101/101f.htm (112 words)

	Lab 2, 2006
		(landmark hint: when you see the optic tracts ascending into the brain, then the MPOA and LPOA are no longer present, but the amygdala is).
		optic tracts terminating in dorsal lateral geniculate nucleus of the thalamus
		Mammillothalamic tract: tract that originates in the mammillary bodies and terminates in the thalamus.
	cda.mrs.umn.edu /~meeklesr/Lab2.html (905 words)

Try your search on: Qwika (all wikis)