Optic Tract

Here we trace hemispheric pathways through the marmoset chiasm and show that fibers from the lateral optic nerve pass directly toward the ipsilateral optic tract without any significant change in fiber order and without approaching the midline, while those from medial regions of the nerve decussate directly. Retrograde labeling from the optic tract confirms this.  

To reach the lesion, a small opening into the brain was created near the optic tract. Tractography may help protect the optic tract..  

For example, we have found LN is most associated with loss of binocular visual sensitivity normally present in neurons of pretectal nucleus of the optic tract (NOT).  

The subcortical nucleus of the optic tract and dorsal terminal nucleus of the accessory optic system (NOT-DTN), along with the dorsolateral pontine nucleus (DLPN), has been shown to play a pivotal role in controlling slow eye movements.  

The cerebral peduncle, the middle cerebellum, and cingulum had the highest variation in FA, while fornix, optic radiation, and optic tract had the highest variation in ADC.  

Lateral or anterolateral to the mamillary bodies, two small quadrangular spaces (2.5 x 3.5 mm) were found that were limited laterally by the junction of the optic tract and crus cerebri.  

In the control anterior optic tract, all ND-positive glial cells (type III) presented immunolabeling to S100 and glutamine synthetase.  

This study investigated the ability of mesenchymal stem cells (MSCs) derived from full-term human umbilical cord blood to survive, integrate and differentiate after intravitreal grafting to the degenerating neonatal rat retina following intracranial optic tract lesion.  

The technique involves macrostimulation with threshold identification of the optic tract and internal capsule. There was no injury to the internal capsule or optic tract throughout the series.  

Normal RGC axon sorting produces axon order in the optic tract that reflects the dorsoventral position of the parent RGCs in the eye. When BMP signaling in the developing eye is genetically modified, RGC order in the optic tract and targeting in the LGN and SC are correspondingly disrupted. These experiments show that BMP signaling regulates dorsoventral RGC cell fate, RGC axon behavior in the ascending optic tract, and retinotopic map formation in the LGN and SC through mechanisms that are in part distinct from EphB signaling in the LGN and SC..  

Interestingly, moderate Wfs1 expression was seen in the optic nerve, particularly in astrocytes, while little Wfs1 was expressed in the optic chiasm or optic tract.  

Using an in vivo optic tract tracing imaging model, we obtained two adjacent regions of interest in the superior colliculi with different water T(1) values (Mn(2+)-enhanced = 1.01 s; unenhanced = 1.14 s) 24 h after intravitreal injection of 3 microL 50 mM MnCl(2).  

Pax2 is essential for the development of the urogenital system, neural tube, otic vesicle, optic cup and optic tract [ Dressler, G.R., Deutsch, U., et al., 1990.  

In both postnatal and adult brains, ERRbeta immunoreactive fibers were distributed in a pattern which perfectly matched the retinal efferent projections: optic tract, supraoptic commissure, hypothalamic suprachiasmatic nucleus, ventral and dorsal geniculate nuclei, pretectal nuclei, and superior colliculus.  

At 7 days after the injection, atrophy of the optic tract was observed on the contralateral side, but not on the ipsilateral side.  

Neuro-ophthalmic manifestations included optic neuropathy (14), cranial neuropathy (4), Horner's Syndrome (1), tonic pupil (1), and optic tract involvement (1).  

Neuroradiological examination revealed an expansive mass in the sella turcica that was compressing the optic tract.  

On neuroimaging, the hemangioblastomas may demonstrate chiasmal or optic tract edema, associated cysts, and T(2) flow voids.  

We provide examples of the use of DTI in the study of the corpus callosum, the anterior white commissure, the corticospinal tract, the limbic system, the long association fibers, the cerebellar peduncles, and the optic tract..  

Imaging showed enhancing nodules in the intracranial segments of both optic nerves posterior to the optic canals and in the anterior optic tract, optic chiasm, and basal leptomeninges.  

In this study, we have utilized immunohistochemical and retroviral lineage tracing methods to characterize the developmental profiles of astrocytes in the chick optic tectum, which develops from both the neural tube and invasion of optic tract. We observed two streams of tectal GFAP-labeled astrocytes originated from the tectal ventricle (intrinsic origin) and the optic tract (extrinsic origin). The extrinsic astrocytes arose from the ventral neuroepithelium of the third ventricle, dispersed bilaterally to the optic tract, and subsequently to the outer layer of optic tectum, indicating migration of astrocytes along retinal ganglion cell axons.  

Slits contribute to the guidance of retinal ganglion cell axons in the mammalian optic tract.  

In the ventral diencephalon, Nogo was expressed on radial glia, most strongly on the dense radial glial midline raphe within the chiasm where uncrossed axons turn and in the initial segment of the optic tract. In the optic pathway, NgR staining was obvious in the vitreal regions of the retina and on axons in the optic stalk and the optic tract, but not in the chiasm.  

GnRH3 fibres in zebrafish began to extend as early as 26 h post-fertilisation and by 4-5 days post-fertilisation had developed into an extensive network reaching the optic tract, telencephalon, hypothalamus, midbrain tegmentum and hindbrain.  

In this study, a 28-day longitudinal in vivo DTI of optic nerve (ON) and optic tract (OT) was conducted to evaluate the temporal and spatial evolution of Wallerian degeneration resulting from the transient retinal ischemia.  

P2X7-positive glial-like small cells were also observed in nerve fiber tracts such as the anterior commissure, corpus callosum (CC), optic tract, and internal capsule.  

The secondary headspot cells are neurons which direct axonal processes into the developing optic tract and so contribute to the primary axon scaffold of the brain.  

In the third patient, with optic tract lesion, figure detection was nearly normal at low density (92%, delta=2) but impaired at noisy background (62%, delta=1).  

The ramipril treatment group showed significant protection from development of white matter lesions in the optic tract, the anterior commissure, the corpus callosum, the internal capsule and the caudoputamen.  

In the optic tract, the nasal and temporal fibers remained intermingled, but there was segregation of dorsal from ventral fibers.  

Follow-up imaging demonstrated persistent enhancement of the coil ball, as well as recurrence and extension of the abnormal signal in the parenchyma and along the optic tract.  

At 21 days after ligation, the white matter lesions including vacuole formation with rarefaction were increased in the optic tract and corpus callosum accompanied by a large increase in glial fibrillary acidic protein (GFAP) immunoreactivity with significantly decreased CNPase-positive oligodendrocytes, all of which were significantly alleviated by the combination therapy with suboptimal doses of cilostazol (30 mg/kg orally) and donepezil (0.3 mg/kg intraperitoneally).  

Eight eyes (42%) had papillitis, 4 eyes (21%) had retrobulbar neuritis, 4 eyes (21%) had retrochiasmal (optic tract) neuritis, and 3 eyes (16%) had neuroretinitis.  

In addition, NT-3(+)/GFAP(+) and NT-3(+)/Vim(+) astrocytes were detected in the ON, chiasm and optic tract in postnatal and adult lizards.  

At the optic chiasm axons make a key binary decision either to cross the chiasmal midline to innervate the contralateral optic tract or to remain uncrossed and innervate the ipsilateral optic tract. Histological analysis of the optic chiasm in man provides anatomical evidence to suggest that, unlike in rodents, uncrossed axons are confined laterally from the optic nerve through to the optic tract and do not mix in each hemi-chiasm.  

The percentage of vacuolated area in the optic tract and percentage values of GFAP-positive area in the frontoparietal cortex were significantly increased in BCCAO.  

DISCUSSION: optic tract lesions are uncommon clinical entities, in which homonymous hemianopia and contralateral band optic atrophy are characteristic.  

But the situation of the tumor, its relationship with third ventricle, hypothalamus, optic tract, vascular structures make its removal often difficult.  

We were able to identify distinct anterior, medial, posterior (now called tectal gray) and olivary pretectal nuclei as well as a nucleus of the optic tract, all with largely similar topographical and chemoarchitectonic features to the homologous regions in therian mammals.  

In half the cases, the function of the central motoneuron and optic tract was found to be restored..  

Fifteen patients had adenoma contact with the optic tract.  

OBJECTIVE: To test various cellular and molecular approaches in attempts to replace retinal ganglion cells (RGCs) in depleted retinas or, more usually, promote the survival of endogenous injured RGCs and stimulate axonal regeneration after ON or intracranial optic tract (OT) injury.  

Immunoreactivity for GH is also traced through the optic nerve head, at the back of the eye, into the optic nerve, through the optic chiasm, into the optic tract and into the stratum opticum and the retinorecipient layer of the optic tectum, where the RGC axons synapse.  

BACKGROUND: The lateral geniculate nucleus (LGN) is the site at which ganglion cell axons of the optic tract synapse with neurons that form the optic radiations.  

Finally, using a kinesin light chain 1 knockout mouse, we find that conventional kinesin is a participant but not essential to neuronal transport of Mn2+ in the optic tract.  

The results showed that, relative to the SC, the EB exhibits significantly reduced WM volumes in the optic tract and optic radiation and significant GM losses in the early visual cortex.  

RGCs with reduced function of Xena/XVASP proteins extended fewer axons out of the eye and possessed dynamic lamellipodial growth cones missing filopodia that advanced slowly in the optic tract.  

The involvement of the optic nerve, the chiasma, and the optic tract by a cavernoma has been reported in only three patients. This is the first reported instance of complete resection of a cavernoma involving the optic nerve, the chiasm, and the optic tract..  

The most frequent combination in NFI patients with more than one pilocytic astrocytoma is optic tract/hypothalamic and brainstem.  

MRI scan revealed multiple enhancing lesions involving the optic chiasm, left optic tract, right lateral geniculate body, and right optic radiation in the temporal lobe.  

In ventral diencephalon, it was localized largely on the chiasmatic neurons that project processes to the chiasmatic midline and the optic tract. Colocalization of hyaluronan and CD44 was observed only in the midline but not lateral domains of the chiasmatic neurons, suggesting a hyaluronan/CD44-mediated mechanism that controls axon routing at the midline but not at the optic tract and the retina..  

On E13, Smo expression was detected in the optic nerves and ventral diencephalon, but only in the superficial region of the optic tract on E14.  

Immunocytochemical examination revealed CYC-like antigen in the pars intercerebralis, dorsolateral protocerebrum, dorsal optic tract, tritocerebrum of the brain and the subesophageal ganglion..  

The lesion locations in congruent HH vs incongruent HH included occipital lobe in 47.9% vs 21.3%, occipital lobe and optic radiations in 8.3% vs 5.6%, optic radiations in 32.4% vs 50.6%, optic tract in 7.2% vs 16.3%, and other locations in 4.2% vs 6.3% (P < .0001). Although there was a trend toward more congruent HH for lesions of the posterior visual pathways (P < .001), 50% of optic tract lesions and 59% of optic radiation lesions produced congruent HH. The rule of congruency should be used cautiously and may not apply to optic tract lesions..  

In the hypothalamus, high density of CTLA-2alpha mRNA labeling was seen in the suprachiasmatic nucleus (Sch), optic tract, arcuate nucleus, and median eminence.  

The nucleus of the optic tract (NOT) has been implicated in the initiation of the optokinetic reflex (OKR) and in the modulation of visual activity during saccades.  

It is composed of three small round globular units which protrude the basal surface of the brain along the optic tract. Like the human LTN, the rodent PV1-nucleus is subdivided into three units and lies along the optic tract.  

METHODS: Brain slices of E13-E15 mouse embryos containing the optic pathway from the eyes to the optic tract were prepared and cultured in DMEM/F12 in the presence of 10% fetal bovine serum at 37 degrees in a rolling incubator for 5 h.  

Fifty-nine patients with anterior optic tract (AOT) lesion concurrent with type neurofibromatosis (NF-1) were followed up for 1 to 36 years (median 5 years).  

Gliomas of the anterior optic tract (AOT) (optic nerves, chiasms, and visual tracts) are benign slowly growing tumors usually detectable in childhood.  

Subarachnoid hemorrhage following pituitary apoplexy is rare, and optic tract hemorrhage after the apoplexy is extremely rare. We report a case of optic tract hemorrhage after apoplexy that is not associated with hematologic disorders..  

Activation of metabotropic glutamate receptors (mGluRs) by agonists or optic tract stimulation increases the output of these presynaptic dendrites leading to increased inhibition of thalamocortical neurons. We found that the group I mGluR (mGluR(1,5)) agonist (RS)-3,5-dihydroxyphenylglycine (DHPG) or optic tract stimulation produced a robust increase in spontaneous IPSCs (sIPSCs) in thalamocortical neurons that was attenuated by the selective mGluR(5) antagonist 2-methyl-6-(phenylethynyl)pyridine hydrochloride (MPEP). Furthermore, the enhanced sIPSC activity by optic tract stimulation was reduced when paired with corticothalamic fiber stimulation.  

Both sides (eyes) specimens of aqueous humor, cornea, iris, lens, vitreous, conjunctiva, sclera, ciliary body, choroid, retina, optic nerve, optic tract and olfactory bulb were weighed, and blood samples were measured, before combustion in tissue oxidizer and radioactive liquid scintillation counting.  

Other (predominantly dopaminergic and optic tract) nuclei also retained reduced [ (125)I]mAb 270 labeling in alpha4(-/-) sections.  

The uncus was related medially to the posterior cerebral artery, anterior choroidal artery, and optic tract.  

No FDG was accumulated in the remaining optic tract.  

Magnetic resonance imaging (MRI) demonstrated a hyperintense lesion in the area of the right posterior thalamus in one patient and enhancing lesions in the deep white matter of the temporal lobes bilaterally with contrast enhancement of the right optic tract in the second patient.  

T2-weighted images of wild-type and heterozygous shiverer mice show regions of hypointensity corresponding to the major myelinated tracts, including the optic nerve and the optic tract of the CNS, whereas shiverer mice have no regions of low intensity and therefore no detectable myelinated areas. In shiverer mice, micro MRI can discern hypomyelination throughout the brain, including the optic tract, and these changes correlate with longer VEP latencies.  

In addition, from E70-130 VMAT2 and SERT were observed in all the sensory cranial nerves, the olfactory nerve, the gustatory, the trigeminal, the auditory fibers, in the retinal ganglion cells, and the optic tract up to the lateral geniculate nucleus and the superior colliculus.  

Anatomical tracing studies and intracellular recordings have suggested that the polarization vision pathway in the locust brain involves the anterior optic tract and tubercle, the lateral accessory lobe, and the central complex of the brain. To investigate whether visual pathways through the anterior optic tract mediate polarotaxis in the desert locust, we transected the tract on one side and tested polarotaxis (1) with both eyes unoccluded and (2) with the eye of the intact hemisphere painted black. The experiments show that the anterior optic tract is an indispensable part of visual pathways mediating polarotaxis in the desert locust..  

In this review we present the current state of knowledge pertaining to RGC responses to injury, neurotrophic and gene therapy strategies aimed at promoting RGC survival, and how best to promote the regeneration of RGC axons after optic nerve or optic tract injury.  

The staining pattern for the PLP/DM20 and MBP overlapped during the lizard ontogeny and was first observed at E39 in cell bodies and fibers located in the temporal optic nerve, optic chiasm, middle optic tract, and in the stratum album centrale of the optic tectum (OT).  

OBJECTIVE: To determine the percent decussation of pupil input fibers in humans and to explain the size and range of the log unit relative afferent pupillary defect (RAPD) in patients with optic tract lesions. PARTICIPANTS AND CONTROLS: Five patients with a unilateral optic tract lesion. METHODS: The pupil response from light stimulation of the nasal hemifield, temporal hemifield, and full field of each eye of 5 patients with a unilateral optic tract lesion was recorded using computerized binocular infrared pupillography. CONCLUSIONS: In patients with a unilateral optic tract lesion, the pupillary responses from full-field stimulation to each eye are the same as comparing the functioning temporal field with the functioning nasal field. Its magnitude does not correlate with the difference in the number of crossed and uncrossed axons, but its sidedness contralateral to the side of the optic tract lesion is consistent with the greater percentage of decussating pupillomotor input..  

Radiographic studies at 6 months of age (age at initial presentation) revealed a large hypothalamic lesion occupying proximal portions of the optic nerves, chiasm and right posterior optic tract.  

Among her many contributions, Loewenfeld provided rigorous observations about Adie tonic pupil, anisocoria in optic tract lesions, Argyll Robertson pupil, oculomotor paresis with cyclic spasms, and innovations in electronic recordings of pupil movement..  

RGC axons extend in the optic tracts in a manner that correlates with the expression in the hypothalamus and epithalamus of a soluble factor inhibitory to RGC axon outgrowth. Here, we show that slit1 and slit2, known chemorepellents for RGC axons expressed in specific regions of the diencephalon and telencephalon, help regulate optic tract development. This demonstrates that Slits play an important role in directing the guidance of post-crossing RGC axons within the optic tracts but are not required for target innervation..  

In 1.5-4.5 months after monocular enucleation calbindin (Calb)-, parvalbumin (Parv)- and calretinin (Calr)-labeling was found in fragments of degenerated retinal fibers in the contralateral optic tract and in some retinorecipient structures (optic tectum, GLd and GLv).  

Less often, the nucleus of the optic tract may be involved.  

Slit2 and Slit1/2 double mutants display malformations in callosal development, and in corticothalamic and thalamocortical targeting, as well as optic tract defects.  

In the lateral geniculate nucleus, however, BDNF mRNA was not detected, and BDNF protein was restricted to punctate and fiber-like structures in the neuropil, especially in the most superficial part of the dorsal lateral geniculate nucleus, just below the optic tract.  

The lesion was occipital in 14 (12.5%) patients, associated with optic radiation in 26 (23.2%) and the optic tract in 12 (10.7%), and multiple in 60 (53.6%).  

In experiments using a severed optic tract in the hamster, we show that regenerated axons reconnect to target tissues with sufficient density to promote functional return of vision, as evidenced by visually elicited orienting behavior.  

In the vehicle group, increased vacuolation and rarefactions in the white matter were accompanied by extensive activation of both microglial and astroglial cells with suppression of oligodendrocytes in association with increased TNF-alpha production, caspase-3 immunoreactivity and TUNEL-positive cells in the white matter including optic tract.  

The transient expression of tyrosine hydroxylase is observed in fibers of the optic tract during fry and juvenile development.  

In a meticulous literature review, 42 published cases of patients with vascular malformations within optic nerves, chiasma and/or optic tract were found, 30 of them being diagnosed as cavernous haemangiomas. Surgical treatment resulted in major improvement in most patients.We include a further patient with a cavernous haemangioma of the optic chiasma and left optic tract who presented with an acute defect of the right visual field and severe retro-orbital pain.  

To obtain basic information about the structural diversity and functional specificity of chondroitin sulfates (CSs) in the formation of the retinotectal pathway in chick embryos, the distribution of CSs around the optic tract was investigated by using anti-CS monoclonal antibodies with different specificities. The MO-225 monoclonal antibody recognizes CSs that are rich in the D-unit [ GlcA(2S)beta1-3GalNAc(6S)]; the MO-225 epitopes were distributed in the diencephalotelencephalic boundary and the neuropil encircling the optic tract. In addition, they were distributed on membrane surfaces of the retinal axons running in an interface layer in contact with the neuropil encircling the optic tract. The results suggest that D-unit-rich CSs are involved in delimiting the border of the optic tract and in the chronological sorting of the retinal axons..  

In this study, we investigate oligodendrocyte lineage cells in the embryonic optic tectum of chick, which develops from the dorsal region of the neural tube and invasion of optic tract. Our results reveal that OPCs dispersed bilaterally along the optic tract and then migrated to the optic tectum in the stratum opticum (SO).  

Both Sema3d knockdown and ubiquitous overexpression induced aberrant ipsilateral projections, suggesting that Sema3d normally guides axons into the contralateral optic tract. Our results indicate that a proper balance of Sema3d is needed at the midline for the progression of RGC axons from the chiasm midline into the contralateral optic tract..  

The cisternal segment of the anterior choroidal artery and the optic tract formed a neurovascular bundle. The branches arising from the plexal segment supply the lateral geniculate body, the thalamus and the optic tract.  

Dopamine (2-100 microm) strongly suppressed excitatory synaptic transmission in dLGN relay neurons that was evoked by optic tract stimulation and mediated by both N-methyl-d-aspartate and non-N-methyl-d-aspartate glutamate receptors.  

Cranial MRI showed an AC in left middle fossa with expansion to suprasellar cisterna and several abnormalities like left temporal lobe hypoplasia, left optic tract and bilateral olfactory bulb hypoplasia and left hypothalamic hypoplasia..  

An aberrant U-shaped fiber bundle immediately caudal to the optic tract connects the left and right sides of the Fz3(-/-) thalamus and likely represents a default pathway for thalamic axons that failed to enter the internal capsule.  

In the corpus callosum and the optic tract, white matter damage observed with Klüver-Barrera staining was significantly attenuated in the minocycline-treated group compared to saline-treated controls.  

optic tract stimulation also evokes plateau-like depolarizations that are mediated by the activation of L-type Ca2+ channels.  

Tetanic stimulation of the optic tract, in which catecholamine fibers also course near or through, produced a strong depolarization that consisted of a fast and slow component. Our results suggest that tetanic stimulation of catecholamine fibers within the optic tract produces synaptic release of norepinephrine and dopamine that in turn activates both alpha(1)-adrenergic and D1-like dopamine receptors leading to a robust membrane depolarization.  

Additional stimulation of the optic tract demonstrated that some somatosensory neurons had bimodal responses. The responses of those in the middle layers appeared to participate in avoidance behavior, based upon previous CSD analysis of the tectum using optic tract stimulation.  

A major hallmark of NF1 is the development of benign tumors, including peripheral neurofibromas, plexiform neurofibromas, gliomas of the optic tract, other low grade gliomas, and pheochromocytomas.  

The accessory optic system (AOS) is formed by a series of terminal nuclei receiving direct visual information from the retina via one or more accessory optic tracts. In addition to the retinal input, derived from ganglion cells that characteristically have large receptive fields, are direction-selective, and have a preference for slow moving stimuli, there are now well-characterized afferent connections with a key pretectal nucleus (nucleus of the optic tract) and the ventral lateral geniculate nucleus.  

Research over the past two decades in mammals, especially primates, has greatly improved our understanding of the afferent and efferent connections of two retinorecipient pretectal nuclei, the nucleus of the optic tract (NOT) and the pretectal olivary nucleus (PON).  

The DC receives excitatory signals from the ipsilateral nucleus of the optic tract (NOT) and inhibitory signals from the contralateral nucleus prepositus hypoglossi (NPH).  

However, the majority of regenerating axons, appearing to follow the existing optic tract and visual pathways, entered the visual targets that were ipsilateral to the nerve injury.  

On magnetic resonance imaging and helical computed tomography, the left optic tract was obscured by suprasellar calcified lesions. Incongruous homonymous hemianopsia due to optic tract damage is usually caused by tumor or aneurysm.  

Nonetheless, reports in a variety of species indicate that some aspects of retinotopic order exist within the optic tract, leading to the suggestion that this "preordering" of retinal axons may play a role in the formation of the mature tectal map. For these reasons, we have undertaken a quantitative study of the degree of retinotopic order within the optic tract and nerve of wild-type mice both before and after the development of the retinotectal map.  

Our data show that mutations in SOX2 can cause not only anophthalmia, but also aplasia of the optic nerve, chiasm and optic tract, as well as modest bilateral sensorineural hearing loss, and global developmental delay, underscoring the importance of SOX2 in early human eye and brain development..  

PURPOSE: To clarify the accuracy, sensitivity, and specificity of optic tract edema in the diagnosis of craniopharyngiomas. RESULTS: Edema along the optic tracts was detected in 7 of 11 craniopharyngiomas, giving a sensitivity of 63.6% (95% CI = 30.8-89.1) for our series and 66.7% (95% CI = 47.2-82.7) for the pooled numbers. CONCLUSION: optic tract edema, commonly seen in craniopharyngiomas, is a useful MR finding for distinguishing craniopharyngiomas from other parasellar tumors with considerable sensitivity and high specificity..  

We used PCR techniques to detect viral DNA and RNA and electron microscopy immunohistochemistry and Western blotting to detect viral proteins in specific portions of the optic tract.  

Learning to respond to electrical stimulation of the optic tract produced no tendency to respond to such stimulation of striate cortex.  

BACKGROUND: optic tract syndrome (OTS) is characterized by incongruous homonymous hemianopia and a perpendicular pattern of bilateral optic atrophy due to the optic tract lesion. Because of a relative afferent pupillary defect in her left eye and left-sided homonymous hemianopia, we suspected right-sided optic tract damage, although magnetic resonance imaging detected no intracranial lesion.  

Harry Moss Traquair (1875-1954) was one of the founders of neuro-ophthalmology, being concentrated on bitemporal hemianopia, the course of the geniculo-calcarine visual pathway, pituitary tumours, optic nerve diseases (including acute retrobulbar neuritis), tobacco amblyopia and traumatic lesions of the optic tract.  

PURPOSE: To evaluate techniques for anatomical and physiological imaging of the intracranial optic nerve (ON), optic chiasm (OC), and optic tract (OT) at 3T with the aim of visualizing axonal damage in multiple sclerosis (MS).  

We have investigated this role by making field EPSP recordings in response to optic tract stimulation in superior colliculus slices taken from rats aged from P14 to P180. Pairing of optic tract stimuli (20 ms separation) resulted in paired-pulse depression at all ages.  

Astrocytes reacted to changes in the optic tract at all time points, and strong glial reactions also occurred in the target areas of retinal fibers, indicating damage to the retina and optic nerve. Nestin labeling was elevated in the optic tract.  

When matching the locations of signal reductions in the in vivo MRI to the template of basal nuclei based on the postmortem brain, signal intensity was decreased in areas corresponding to anterior lateral and anterior medial nucleus basalis Meynert and increased in the third ventricle, the transverse fissure and the optic tract in patients with Alzheimer's disease compared with controls.  

Whole cell recordings showed that monosynaptic postsynaptic currents (PSCs) evoked in LGNv neurons by optic tract stimulation were blocked by glutamate receptor antagonists. In a second set of experiments, the effect of releasing endogenous ACh by stimulating the lateral portion of the LGNv through a separate conditioning electrode before optic tract stimulation was examined.  

At E13-E15, this neuronal array changes gradually to a configuration that facilitates contact with the optic axons only at the midline and the initial segment of the optic tract. This difference between the central and lateral domains raises the possibility that the chiasmatic neurons may regulate the patterning of axon orders at the midline and the optic tract through presentation of distinct combination of guidance cues at these strategic positions in the optic pathway.  

Fasciculation within the optic tract and adhesion within the tectal neuropil are regulated by vrt, coma, bluk, clew and blin.  

These include the oculomotor, trochlear, anterior pretectal, Edinger-Westphal, and the terminal nuclei; all layers of the superior colliculus, interstitial nucleus of the medial longitudinal fasciculus, supraoculomotor periaqueductal gray, nucleus of the optic tract, the inferior olive, and raphe interpositus.  

Many hNT fibers were often associated with ipsilateral and contralateral white matter tracts--corpus callosum, rostral migratory stream, optic tract, and external capsule.  

In teleost fish an additional group of axons extends along the optic tract and delivers putative neuromodulators to the retina.  

There were no significant differences in MBP and CNP old in the cerebral cortex and the optic tract between SAMR1 and SAMP8 at 10 months.  

However, traumatic lesions of the optic tract are relatively rare. We present a case with posttraumatic left homonymous hemianopia who had signal intensity change at the ipsilateral optic tract on MR imaging and ipsilateral occipital hypoperfusion on SPECT imaging..  

Agonist treatment did not affect EPSCs from stimulation of the optic tract.  

Specifically, we investigated the role of the pretectal nucleus of the optic tract (NOT) in vestibular compensation after hemilabyrinthectomy (HL) in rhesus monkeys.  

For the first time in any species, this paper investigates the influence of motion adaptation on both the contrast and TF responses of neurons in the retino-pretectal pathway by recording from direction-selective neurons in the nucleus of the optic tract (NOT) of the marsupial wallaby, Macropus eugenii.  

Field potential responses electrically-elicited from the optic tract and recorded in the optic tectum disappeared during KCl-elicited SD and recovered 10-20 min thereafter.  

Blockade of GABAergic transmission revealed a field EPSP in response to optic tract stimulation which was sensitive to the NMDA antagonist AP5.  

Contact with the chiasma or optic tract was not regarded as a contraindication for gamma knife radiosurgery and such contact was observed in 32% of the skull base meningiomas treated.  

Tumors involved the brainstem in 22 cases, cerebellum in four, thalamus in six, temporal lobe in five, frontal lobe in four, and parietal lobe in three, as well as the hypothalamus, corpus callosum, insular cortex, optic tract, and third ventricle in one patient each.  

Thirteen weeks after surgery, the animals were sacrificed and astrocytes and microglia were labeled immunocytochemically in the internal capsule, the corpus callosum and the optic tract. The astrocytic proliferation was enhanced by cerebral hypoperfusion in the optic tract, and reduced by diazoxide in DMSO, but not by DMSO alone in the corpus callosum. After carotid artery occlusion, microglial activation was enhanced two-fold in the corpus callosum and four-fold in the optic tract. DMSO decreased microglial activation in the optic tract, while diazoxide in DMSO, but not DMSO alone, restored microglial activation to the control level in the corpus callosum. In summary, the rat optic tract appeared to be particularly vulnerable to ischemia, while the effect of diazoxide was restricted to the corpus callosum.  

In situ hybridization on postnatal brain slices showed rho2 mRNA expression from newborn in superficial gray layer (SGL) of superior colliculus (SuC), and from the first postnatal week in the hippocampal CA1 region and pretectal nucleus of the optic tract.  

Retinal ganglion cell (RGC) axons are topographically ordered in the optic tract according to their retinal origin. In zebrafish dackel (dak) and boxer (box) mutants, some dorsal RGC axons missort in the optic tract but innervate the tectum topographically. This genetic evidence that heparan sulfate proteoglycan function is required for optic tract sorting provides clues to begin understanding the underlying molecular mechanisms..  

Field excitatory postsynaptic potentials (fEPSPs) evoked by optic tract stimulation were recorded from 300 microm slices of the adult pigmented rat superior colliculus at 34 degrees C.  

The CYC- and aaNAT-like antigens were further colocalized in small groups of neurons in the pars intercerebralis, at the venter of the optic tract, and in the subesophageal ganglion.  

In 4 patients (19%) the signs of lesions in the optic tract have been found. In patients with the lesions in the optic tract there were severe disorders of breathing during sleep: AHI >60, mean SaO2 at the end of the apneas <86% and minimal SaO2 at the end of the apneas <70%. The authors conclude that in OSA patients there is a high risk of the lesions of the optic tract as a consequence of severe and repetitive hypoxemia during sleep..  

Chiasm defects include axon stalling in the chiasm and a reduction in the total number of RGCs projecting to the optic tract.  

These lesions were the most intense in the corpus callosum adjacent to the lateral ventricle but were mild in the anterior commissure and optic tract.  

They do not take the marginal optic tract, but pass medially to the chiasmatic fascicles, from the preoptic region.  

3) Pretectal injections that included the nucleus of the optic tract (NOT), and the olivary pretectal nucleus (OLN), labeled terminals only over nontwitch motoneurons, in the contralateral C group and in the S group.  

Staining with Fluoro-Jade revealed time-dependent degeneration of nerve fibers and terminals (with PSP and TPPi), or cell bodies (with TPPi) in lamina VII, spinocerebellar, and medial pontine-spinal tracts of the lumbar spinal cord, in white matter and mossy fibers of foliae I-V and IX of the cerebellum, and in medullary, pontine, and midbrain nuclei and paleostriatal fibers surrounding the optic tract.  

In all three species, visually elicited behavioral responses were absent throughout regeneration, a result supported electrophysiologically; axonal tracing revealed that only a small proportion of RGC axons crossed the lesion and none entered the contralateral optic tract.  

After 14 days, the myelin was degraded in the corpus callosum, internal capsule and the optic tract in Klüver-Barrera staining.  

We studied the development of optic tract evoked field potentials (FP) in the rodent superior colliculus (SC) and the effect of GABA antagonists upon their development and upon induction of long-term depression (LTD). The optic tract was stimulated while recording from the superficial grey layer.  

They can lead to severe complications such as hypopituitarism with secondary hypogonadism, hypothyroidism, and adrenocortical insufficiency, compression of the optic tract or obstructive hydrocephalus.  

Magnetic resonance imaging showed a partially thrombosed giant aneurysm of the right internal carotid artery, with enhancement of the chiasm and right optic tract adjacent to the aneurysm.  

BACKGROUND AND PURPOSE: Perivascular (PV) spaces are known to distend and cause edema along the optic tract (OT) in pituitary-region tumors.  

We describe a case of ganglioglioma of the right optic tract in a 52-year-old woman.  

In E13-E15 mouse embryos, when most optic axons grow in the chiasm and the optic tract, phosphacan and neurocan were observed in the inner regions of the retina.  

In the normal frog, axons from the peripheral retina arising at the temporal pole course superficially in the middle stream of the diencephalic optic tract. Axons from more central regions of the retina tend to occupy deeper levels of the optic tract. The regenerated optic tract does not regain its normal organization, e.g., axons of peripheral nasal origin are spread out widely over the entire width of the tract. The concentration of temporal axons in the middle stream of the optic tract after regeneration may now be understood in terms of the expression pattern of the ephrin-A class of receptor tyrosine kinase ligands in the cellular matrix of the optic tract. The ephrin-As, which have a repellent effect on growing temporal retinal axons, are concentrated in and along the margins of the diencephalic optic tract and essentially absent from its middle stream. In contrast, the growth pattern of regenerating peripheral nasal axons would not be affected by the ephrin-A gradient in the optic tract..  

The nucleus of the optic tract, the olivary pretectal nucleus, and the anterior and posterior pretectal nuclei were innervated by the retina.  

In rodents, most RGC growth cones then cross the ventral midline to join the contralateral optic tract; those that do not cross join the ipsilateral optic tract.  

A junctional visual field defect was present, and an MRI revealed a contrast-enhancing mass involving the right optic nerve, lateral chiasm, optic tract, and cavernous sinus.  

Fluoro-Jade staining following WDIA+H injury revealed damage to fibers in the optic tract, lateral olfactory tract, corpus callosum, anterior commissure, caudate-putamen, brain stem, and cerebellum.  

Thirteen weeks after the onset of occlusion, markers for astrocytes, microglia, and myelin were found to be labeled by means of immunocytochemistry in the corpus callosum, the internal capsule, and the optic tract. The ultrastructural integrity and oligodendrocyte density in the optic tract were investigated by electron microscopy. Quantitative analysis revealed that chronic cerebral hypoperfusion caused mild astrogliosis in the corpus callosum and the internal capsule, while astrocytic disintegration in the optic tract increased by 50%. Further, a ten-fold increase in microglial activation and a nearly doubled oligodendrocyte density were measured in the optic tract of the hypoperfused rats as compared with the controls. Finally, vacuolization and irregular myelin sheaths were observed at the ultrastructural level in the optic tract. In summary, the rat optic tract appears to be particularly vulnerable to ischemia, probably because of the rat brain's angioarchitecture.  

All the participants showed no abnormal signs in their intracranial space and optic tract causing optic nerve atrophy and visual field defect, as confirmed by MRI.  

The MR imaging depicted edema spreading along the optic tract on fluid-attenuated inversion recovery (FLAIR) images. Edema spreading along the optic tract was reported as a characteristic MR imaging finding for diagnosis of craniopharyngiomas or optic nerve glioma. It was a rare case of secondary lymphocytic hypophysitis caused by Rathke's cleft with edema along the optic tract..  

We compared the horizontal optokinetic reaction (OKR) and response properties of retinal slip neurons in the nucleus of the optic tract and dorsal terminal nucleus (NOT-DTN) of albino and wild-type ferrets (Mustela putorius furo).  

To identify specific proteoglycans increased during regeneration, we have used proteoglycan preparations from regenerating goldfish optic tracts to produce monoclonal antibodies. Western blot analysis shows a 28-kD antigen reacting with our 1G4/G5 antibody is present in optic tract 21 days after nerve crush, but absent in nonregenerating tract.  

In animals with large bilateral lesions of the lateral geniculate body/optic tract, ganglion cells labeled with PRV152 are retrogradely infected from only the SCN.  

The axonal transport of retinal-derived BDNF in segments of the optic nerve as well as tectal-derived BDNF protein transported in segments of the optic tract were both significantly reduced after very brief periods of activity blockade.  

In the adult brain, WOX1 is abundant in the epithelial cells of the choroids plexus and ependymal cells, while a low to moderate level of WOX1 is observed within white matter tracts, such as axonal profiles of the corpus callosum, striatum, optic tract, and cerebral peduncle.  

At the threshold of the optic tract, L1 immunoreactivity was maintained only in a subpopulation of axons, whereas PSA-NCAM staining was dramatically elevated in axons at the caudal part of the tract. Moreover, intense PSA-NCAM expression was also observed in the tract of postoptic commissure (TPOC), which lies immediately caudal to the optic tract. These early generated commissural axons together with the regionally specific pattern of cell adhesion molecule expression on the optic axons may control formation of the partial retinotopic axon order in the optic tract through homophilic or heterophilic interactions that involve PSA-NCAM..  

PACAP-containing retinal fibres were also found in the ventrolateral preoptic nucleus, the anterior and lateral hypothalamic area, the subparaventricular zone, the ventral part of the lateral geniculate nucleus and the nucleus of the optic tract.  

optic tract stimulation increases inhibitory activity in thalamic relay neurons in a frequency- and intensity-dependent manner and is attenuated by mGluR antagonists.  

In optic tract, AA mediates NCAM and L1 stimulation of axon growth by activating presynaptic protein kinase C (PKC) to phosphorylate GAP-43 and stabilize F-actin, and, if present in tectum, this growth control pathway could be modulated by postsynaptic activation.  

This is followed by a displacement of surviving axons to the medial part of the optic tract (OT) within 2 weeks.  

Remote activation of microglial cells of the optic tract in EAU did not result into IL-16 expression.  

Moreover, LY354740 administration per se significantly increased c-Fos expression in regions processing sensory information, including the paraventricular and lateral geniculate nucleus of the thalamus as well as the nucleus of the optic tract and superior colliculus.  

S3 labeling of the optic pathway is also complex, being initially strong in the retinal ganglion cells, optic tract, and chiasma but thereafter being lost except in a proportion of postchiasmal axons.  

We used single-unit extracellular recording techniques to characterize the temporal response properties of individual retinal ganglion cell axons recorded from the optic tract.  

Using EphA3 receptor and ephrin-A5 ligand alkaline phosphatase in situ affinity probes (RAP and LAP, respectively) in whole-mount applications, we report that reciprocally complementary gradients of RAP and LAP binding persist in the optic tract and optic tectum of postmetamorphic frogs, including mature adults. EphA expression in temporal retinal axons in the optic tract was significantly reduced after nerve section but returned during regeneration.  

PURPOSE OF REVIEW: optic tract low-grade gliomas are one of the commonest category of neoplasm presenting in childhood and early adolescence.  

In the vehicle-treated animals, white matter lesions and microglial activation occurred in the optic tract, internal capsule and corpus callosum.  

The ipsilateral PON was devoid of FB-labeled somata, whereas the adjacent nucleus of the optic tract (NOT) contained FB-labeled cells.  

This phenotype is quite distinct from that observed in comparable cells isolated from the optic tract.  

After unilateral enucleation, VGluT2 immunoreactivity in the LGd, SC, nucleus of the optic tract, and nuclei of the accessory optic tract in the contralateral side of the enucleated eye was clearly decreased.  

Stimulating electrodes inserted into the optic tract and light-emitting-diodes as photic stimulation were used to identify the dLG neurons.  

PTT cells were distributed mostly in the nucleus of the optic tract and 93.1% contained gamma amino butyric acid (GABA).  

Edema spreading along the optic tract was reported as a characteristic MR finding for diagnosis of craniopharyngiomas as distinguished from other common parasellar tumors.  

Tenascin-R immunoreactivity is not detectable in the optic nerve, optic tract, or tectal optic neuropil but immediately borders the optic tract caudally. Reducing expression of tenascin-R in 3-d-old larvae in vivo by injecting morpholinos into fertilized eggs led to excessive branching of the optic tract in 86% of all injected larvae compared with 20-37% in controls. Branches were almost exclusively caudal, where tenascin-R immunoreactivity normally borders the optic tract, suggesting a role for tenascin-R in guiding optic axons in the ventral diencephalon by a contact-repellent mechanism..  

The area of vacuoles in the optic tract observed after hematoxylin and eosin staining was significantly reduced in the 200 mg/kg quercetin-treated hypoperfusion group versus the vehicle-treated hypoperfusion group (1.7+/-0.2% versus 3.9+/-0.3%; P<0.05).  

This increased phosphorylation state is not a direct consequence of the decrease in visual activity in these neurons, because we would have expected to see a similar change at shorter or longer post-lesion survival times or in the visually deprived visual cortex of animals in which the left optic tract and the corpus callosum were surgically cut.  

In addition to the interstitial, medial, lateral, and dorsal terminal nuclei, a few fibers of the accessory optic tract may enter the ventral lateral geniculate and the nucleus of the optic tract, though this innervation may not derive from the same ganglion cells innervating the accessory optic nuclei.  

CONCLUSIONS: The techniques of microelectrode recording and microstimulation indicate the location of the internal capsule and optic tract, which allow easy identification of these structure and facilitate PVP target in conjunction with radiofrequency microelectrode stimulation..  

From the results that unilaterally optic tract severed males still showed locomotor circadian rhythmicity (93.1%, n=29) without significantly changing the circadian period (tau) or level of motor activity, we concluded that the right and left optic lobes each contain a circadian pacemaker competent to drive the locomotor circadian rhythm.  

Retinal axons undergo an age-related reorganization at the junction of the chiasm and the optic tract. We have investigated the effects of removal of chondroitin sulphate on this order change in mouse embryos aged embryonic day 14, when most axons are growing in the optic tract. Enzymatic removal of chondroitin sulphate but not keratan sulphate in brain slice preparations of the retinofugal pathway abolished the accumulation of phalloidin-positive growth cones in the subpial region of the optic tract.  

Immunofluorescence microscopy indicated that the number of infected astrocytes was reduced in the proximal optic nerve and eliminated in the optic tract. Results of reverse transcription-PCR indicated that there was no gD mRNA present in the treated optic tract 5 days after infection.  

We have described three types of neurons: types A and B are both located in the lateral and medial vLGN (vLGN-l and vLGN-m, respectively), and type C neurons over the optic tract.  

As early as postnatal day (P) 1-2, 31% of all excitatory postsynaptic (EPSP) activity evoked by electrical stimulation of the optic tract was followed by inhibitory postsynaptic potentials (IPSPs).  

These included the optic tract, superior colliculus, olfactory bulb, and several thalamic relay centers such as the anterior dorsal, medial geniculate, dorsolateral geniculate, ventral posteromedial and ventral posterolateral nuclei.  

BACKGROUND AND PURPOSE: Edema-like change along the optic tract commonly occurs in association with craniopharyngiomas. RESULTS: Edema-like change along the optic tract was visible on the images of four of 25 pituitary adenomas, eight of 11 craniopharyngiomas, one germ cell tumor, and one malignant lymphoma and was not visible on the images of seven meningiomas and five Rathke's cleft cysts. After therapeutic decompression of the optic pathway, the edema-like change disappeared and large Virchow-Robin spaces, present under normal conditions, became visible along the optic tract. Comparison of pre- and post-treatment coronal and axial view MR images revealed that the edema-like change had been located at, along, and/or around the large Virchow-Robin spaces along the optic tract. It is related with distension of normally present large Virchow-Robin spaces adjacent to the optic tract.  

Magnetic resonance imaging (MRI) revealed enhanced mass lesion around AcomA complex and hyperintense signal on optic chiasm and right optic tract by fluid-attenuated inversion recovery image.  

Tumors were located at the thalamus/hypothalamus in 12 cases, optic tract in one case, and the deep cerebral/cerebellar hemisphere in seven cases.  

The patterns of saccadic responses and the modulation of PrGC activity in association with a variety of visual-ocular motor behaviors suggest its potential role as a relay between the parietal cortex and elements of the brain stem ocular motor pathways, such as the superior colliculus and pretectal nucleus of the optic tract..  

For example, prominent staining was noted in the stria medularis, stria terminalis, fasciculus retroflexus, optic tract, and inferior thalamic radiation, structures that seem to connect OL-pc-positive brain regions.  

This study was performed to analyze the diffusion of ICG in the optic tract.  

cGnRH-ir cell bodies are restricted to the optic tract, but few scattered fibers could be detected in different parts of the brain.  

The projections of the nucleus of the optic tract (NOT) were studied in cats using three kinds of retrograde tracers (horseradish peroxidase wheat germ agglutinin (WGA-HRP), dextran fluorescein (DF) and dextran tetramethylrhodamine (DTR)).  

Regenerating goldfish retinal explants were cultured on poly-L-lysine (control) or poly-L-lysine overlaid with membranes isolated from non-regenerating optic tract (OTr) and 10- or 21-day regenerating OTr.  

[ View All ]