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At least 91 records · Page 5Linked to original sources
PubMed1999

Differential anterograde transport of HSV type 1 viral strains in the murine optic pathway.

Active anterograde transport of herpes simplex virus Type 1 (HSV-1) in neurons is often assumed based on early appearance of infection in postsynaptic target cells of a primary infected cell, and is further logically inferred by good evidence of microtubule-motor based mechanisms of retrograde transport. However, direct evidence of mechanisms of anterograde movement of newly synthesized virus in CNS neurons actually has yet to be obtained. In efforts to investigate the latter, we will be greatly aided by viral strains that exhibit differences in their ability to move in an anterograde direction. We compared the anterograde axonal transport of three HSV strains (F strain, H129, and MacIntyre B) in the murine visual system. Equivalent titers of virus were injected intraocularly in BALB/c mice. From 2-6 days after inoculation, segments of the infected optic pathway were harvested and Western blots using an anti-HSV polyclonal antibody performed. H129 traveled very rapidly towards the terminals (3 days post-inoculation). F strain spread more slowly than H129, but also reached terminal regions by 4 days. MacIntyre B accumulated only in the most proximal optic nerve, and was seen only very faintly in distal optic pathway after 5 days. Coincidentally, a single viral protein appeared to be greatly reduced in expression in MacIntyre B. Our results suggest that different viral strains display variability in their capacity to spread anterogradely, and that further comparison of these strains may reveal how virus engages the host cell transport machinery.

Animals↗
PubMed2002

Lymphocytic infundibulo- neurohypophysitis with hypothalamic and optic pathway involvement: report of a case and review of the literature.

BACKGROUND: Lymphocytic adenohypohysitis and lymphocytic infundibulo-neurohypophysitis are rare auto-immune mediated diseases of the anterior and posterior pituitary, respectively. The former usually manifests as insufficiency of anterior pituitary hormone secretion, associated in many patients with disturbances of vision. The latter presents as diabetes insipidus of central origin. They present most commonly in pregnant or postpartum females. There have been infrequent reports in females with no association with pregnancy, and in males. CASE DESCRIPTION: We present a nulliparous female with central diabetes insipidus, pan-hypopituitarism, and severely impaired vision. Magnetic resonance imaging demonstrated a large mass involving the hypothalamus, infundibulum, optic nerves, chiasm, and tracts. At operation, the optic pathways were found to be grossly involved in the inflammatory mass. Histological examination of a biopsy demonstrated a nonspecific, mixed inflammatory infiltrate, composed predominantly of lymphocytes and plasma cells. She responded dramatically to treatment with dexamethasone, with disappearance of the mass on serial imaging studies and improvement in vision. In addition, she received hormone replacement therapy. CONCLUSION: We present a case of lymphocytic infundibulo-neurohypophysitis unique in the degree of optic pathway inflammatory involvement, with a documented response to steroids.

Adrenocorticotropic Hormone↗
PubMed1978

The management and prognosis of gliomas of the optic pathways in children.

A follow-up study was made of 24 children with gliomas of the optic pathways. In gliomas restricted to one optic nerve, total excision should be performed. The prognosis is excellent. Radiotherapy is not indicated. In gliomas of the anterior chiasma a biopsy should be taken; occasionally partial removal is indicated. The prognosis is good. Radiotherapy is indicated only if the follow-up shows a progression in the visual signs. In most cases the growth of the tumour seems to be arrested. The vision remains stable, and most patients have a useful degree of vision in at least one eye. In gliomas of the posterior chiasma with hypothalamic signs the prognosis is poor. A biopsy and radiotherapy are indicated. Occasionally, long remissions are seen.

Adolescent↗
PubMedDate not supplied

Management and prognosis of gliomas of the optic pathways in children.

A follow-up study was made of 24 children with glioma of the optic pathways. In gliomas restricted to one optic nerve, total excision should be performed. The prognosis is excellent. Radiotherapy is not indicated. In gliomas of the anterior chiasm, a biopsy should be taken; occasionally, partial removal is indicated. The prognosis is good. Radiotherapy is indicated only if the follow-up shows a progression in the visual signs. In most cases, the growth of the tumor seems to be arrested. The vision remains stable and most patients have a useful degree of vision in at least one eye. In gliomas of the posterior chiasm with hypothalamic signs, the prognosis is poor. A biopsy and radiotherapy are indicated.

Adolescent↗
PubMed2026

Novel Germline ELP1 Splice-Acceptor Variant in NF1-Negative Optic Pathway Glioma: Expanding the Clinical Spectrum Associated With ELP1 Variation.

We report a 7-year-old boy with NF1-negative optic pathway glioma harboring a novel germline ELP1 splice-acceptor variant (NM_003640.5:c.2205-2A>G) identified by whole-exome sequencing. The variant was likely pathogenic (ACMG/AMP: PVS1, PM2) and inherited from an asymptomatic father, consistent with incomplete penetrance, expanding the limited evidence linking germline ELP1 variation to gliomas.

Humans↗
PubMed1994

Childhood optic pathway tumors associated with ascites following ventriculoperitoneal shunt placement.

Three children with optic pathway gliomas who developed ascites following ventriculoperitoneal shunt placement are presented. In all 3 cases there was an elevated cerebrospinal fluid (CSF) protein level at the time of initial shunt placement. At the time of developing ascites following placement of the ventriculoperitoneal shunt, none of the patients had evidence of infection or tumor seeding in the peritoneal cavity. The ascites completely resolved in each instance after converting the shunt to a ventriculoatrial system. Ascites following ventriculoperitoneal shunt insertion is an uncommon complication. A review of the literature and discussion of the possible etiologic factors in the development of ascites after ventriculoperitoneal shunt placement are presented. For patients diagnosed with optic gliomas, it is suggested that because the tumor is widely exposed to the CSF space, protein exuded by the mass into the subarachnoid space will cause an elevated CSF protein concentration. The elevated CSF protein may then lead to ascites as a result of poor absorption of CSF in the peritoneal cavity after placement of a ventriculoperitoneal shunt. Although ascites following ventriculoperitoneal shunt placement is not typical in patients with optic gliomas, attention should be given to CSF protein levels documented at the time of CSF diversion for hydrocephalus, recognizing that ascites may occur as a result of poor CSF absorption in the periotoneum, subsequently requiring a ventriculoatrial shunt in patients who develop hydrocephalus.

Ascites↗
PubMed1991

Chemotherapeutic treatment of extensive optic pathway tumors in infants.

Two infants, ages 14 and 4 months, with extensive optic pathway tumors were treated with intensive chemotherapy called MADDOC: nitrogen mustard, doxorubicin, cis-platinum, dacarbazine, vincristine, and cyclophosphamide. The first child had hydrocephalus with an enhancing mass at the hypothalamus which followed the optic radiation to include the lateral geniculate body and medial temporal lobe. A v-p shunt was placed, and biopsy revealed a Grade II astrocytoma. One month later, the child developed malignant ascites. Intensive induction chemotherapy was then begun with cis-platinum 100 mg/m2 and cyclophosphamide 3 g/m2 for two initial cycles. The ascites resolved within one week, and chemotherapy was continued for 10 courses of the 6-drug MADDOC regimen. CT scans showed a gradual shrinkage of the tumor mass by approximately 70%. The enhancing areas continued to decrease in size through 20 months after completing MADDOC. The child has not received radiation and is well 4 years 7 months post diagnosis. The second infant had massive enlargement of the right optic nerve with an enhancing chiasmatic mass extending into the suprasellar space, hypothalamus, and brain stem. This infant was not biopsied; she also received induction MADDOC chemotherapy for 12 cycles. CT scans showed a definite decrease in the chiasmatic mass by the fifth cycle, with continued reduction by approximately 40% after 10 months. Twenty-three months from diagnosis there was asymptomatic evidence of tumor growth. The child is being treated with carboplatinum and remains ophthalmologically and radiographically stable 43 months from diagnosis.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1990

Histopathology of anterior parts of the optic pathway in patients with multiple sclerose.

Multiple sclerosis involves the anterior part of the optic pathway of 5 patients with clinically definite multiple sclerosis. No pathological changes were found in the retina. Plaques were found in all optic nerves, in two of three chiasms and in the optic track from one patient. Periphlebitis was found in three optic nerves, and in one chiasm. One patient had plaques as well as periphlebitis in the optic nerves and chiasm but did not show any changes in the brain or the spinal cord.

Adult↗
PubMed1999

Radiation-induced cerebral vasculopathy in children with neurofibromatosis and optic pathway glioma.

Occlusive vasculopathy is a potential complication of radiotherapy in children with optic pathway glioma. With a median follow-up of 7 years, 13 of 69 children in this study developed clinical and radiological signs of occlusive vasculopathy after radiotherapy within a median interval of 36 months. The major risk factor was neurofibromatosis type 1. Radiotherapy should no longer be the first treatment in these settings. When radiotherapy is unavoidable, regular screening for cerebral vasculopathy is mandatory, as preventive treatment is available.

Cerebrovascular Disorders↗
PubMed2001

Size-selective neuronal changes in the anterior optic pathways suggest a differential susceptibility to injury in multiple sclerosis.

Axonal damage is found in both acute and chronic lesions of multiple sclerosis. Direct axon counting in post-mortem tissue has suggested that smaller axons might have a greater susceptibility to damage, but methodological limitations have precluded unequivocal interpretation. However, as neuronal and axonal sizes are linked and neuronal changes would be expected with retrograde or transsynaptic degeneration following axon injury, we hypothesized that an alternative strategy for studying this phenomenon would be to define multiple sclerosis-associated changes in neurones. To test this hypothesis, we measured both axonal loss and neuronal size changes in the anterior optic pathway [including the optic nerve (ON), optic tract (OT) and lateral geniculate nucleus] of the brains of eight patients who died with multiple sclerosis and in eight control brains. The ONs and OTs in brains from the multiple sclerosis patients showed a trend to smaller mean cross-sectional areas (ON, multiple sclerosis = 6.84 mm(2), controls = 9.25 mm(2); and OT, multiple sclerosis = 6.45 mm(2), controls = 7.94 mm(2), P = 0.08) and had reduced axonal densities (ON, multiple sclerosis = 1.1 x 10(5)/mm(2), controls = 1.7 x 10(5)/mm(2); and OT, multiple sclerosis = 1.4 x 10(5)/mm(2), controls = 1.8 x 10(5)/mm(2), P = 0.006). Estimated total axonal counts were reduced by 32 (OT)-45% (ON) in the patients relative to controls (ON, multiple sclerosis = 8.1 x 10(5) axons, controls = 14.8 x10(5), P = 0.05; and OT, multiple sclerosis = 9.1 x 10(5), controls = 13.3 x 10(5), P = 0.02). The size distributions of the magnocellular cells in the lateral geniculate nucleus were similar for the two groups, but in multiple sclerosis brains the parvocellular cells were significantly smaller (mean sizes: multiple sclerosis = 226 microm(2), controls = 230 microm(2), P < 0.001) and had a larger variation in size, suggesting a greater proportion of atrophic neurones. Axon loss in the optic nerves of multiple sclerosis patients correlated strongly with measures of increased dispersion of cell sizes in the parvocellular layer (r = 0.8, P < 0.04). These data demonstrate that both atrophy and decreased density contribute to the substantial axonal loss in the anterior visual pathway of these patients. This appears related to a relatively selective atrophy of the smaller neurones of the parvocellular layer in the lateral geniculate nucleus, supporting the hypothesis that smaller axons may be preferentially susceptible to injury in multiple sclerosis.

Adult↗
PubMed1979

Axoplasmic and nonaxoplasmic transport along the optic pathway of albino rabbits; a theoretical pattern of distribution.

Distribution of nonaxoplasmically transported material along the optic pathway of the rabbit was studied after blockage of the axonal flow by vinblastine, and a clear pattern of distribution of the axoplasmic transport was deduced by subtraction from the pattern seen in nontreated animals. Vascular participation in the nonaxoplasmic transport was certified by autoradiographic studies. The theoretical pattern of distribution of axoplasmic transport in the optic system under ideal conditions was calculated from an idealized model system. From the comparison of theoretical and experimental patterns, partial obstruction of the axonal flow likely occurs at the optic foramen and chiasma.

Animals↗
PubMed1999

Spontaneous improvement of optic pathway lesions in children with neurofibromatosis type 1.

Two cases of spontaneous improvement of optic pathway lesions in neurofibromatosis type 1 are reported. At time of diagnosis the children were aged 21 and 32 months respectively; they have been followed by both MRI and clinical evaluation for 5 and 4 years. MRI findings of the first 19 months of follow-up for Case 1 have been described by us before. On MRI serial evaluation, Case 1 showed an almost complete normalization of the size of lesions and a resolution of enhancement, whereas Case 2 showed a slight decrease in the size of lesions and a resolution of enhancement. From the clinical point of view Case 1 showed a normalization of his clinical signs, whereas in Case 2, a visual improvement was only slight, if at all present. In Case 1, the clinical improvement seemed to follow the spontaneous regression of the lesions detected by MRI.

Child, Preschool↗
PubMed1998

Distribution, size and number of axons in the optic pathway of ground squirrels.

The present study has examined the distribution of axons of differing sizes in the optic pathway of the ground squirrel. Axon diameters were measured from electron micrographs at various locations across sections of the optic nerve and tract, and total distributions and numbers were estimated. In both the nerve and tract, roughly 1.2 million optic axons were present. The population of optic axons had a unimodal size distribution, peaking at 0.9 microm in diameter and having an extended tail toward larger diameters. Local axon diameter distributions in the optic tract indicated distinct (though partially overlapping) axon diameter classes, including one of fine sizes peaking at 0.8-0.9 microm, a second of medium sizes peaking around 1.7-1.8 microm, and a third composed of the larger fibers with diameters up to 4.8 microm. The fine-caliber axons were found at all locations in the tract, and were the only axons present immediately adjacent to the pia, while the medium- and coarse-caliber axons were found at deeper locations. Curiously, the larger axons were found primarily in the medial parts of the tract, where axons from the dorsal retina normally course. A similarly restricted distribution of the larger axons was observed in the dorsotemporal parts of the optic nerve, suggesting that this difference in the tract may relate to an asymmetric distribution of ganglion cells on the retina giving rise to these axons. Measurements of axonal size taken within the optic fiber layer in dorsal and ventral parts of the retina confirmed this asymmetry, consistent with previous demonstrations of soma size differences in the dorsal versus ventral retina. The partial segregation of axons by size in the optic tract of the ground squirrel then reflects both the asymmetric distribution of retinal ganglion cell classes and the chronotopic reordering of optic axons that occurs within the chiasmatic region.

Animals↗
PubMed1987

MRI of the normal orbit and optic pathway.

In recent years MRI has made increasingly important contributions to the evaluation of the orbit and optic pathway. The unique ability of MRI to demonstrate soft tissue contrast allows exquisite demonstration of anatomic detail. MRI technique and normal anatomy are reviewed. Today, optimal ophthalmologic work-up is often incomplete without the critical input of the radiologist.

Aqueous Humor↗
PubMed2006

Management of child optic pathway gliomas: new therapeutical option.

OBJECTIVE: To present our experience in the treatment of child optic pathway gliomas in the last 25 years. MATERIAL AND METHODS: Seventeen children under 10 years of age have been analyzed and assessed from clinic, ophthalmologic, endocrinologic, neurological, neuropathologic, and imaginologic points of view. RESULTS: Predominance of female patients, 10 girls and 7 boys between 6 and 122 months old; mean age was 3 years and 8 months. The most frequent symptoms have been ophthalmologic and visual alterations in all 17 patients, endocrine alterations in 10, and neurological signs in 6. One of the patients presented neurofibromatosis type 1 (NF1), another patient had Down syndrome. Diagnosed using computed tomography or/and magnetic resonance imaging, histological studies showed pilocytic astrocytomas in 13 cases and a fibrillary astrocytoma grade II in 1 case. There were three patients without histological diagnosis; one of them had NF1. The treatment consisted of surgery, external beam radiotherapy, chemotherapy, and brachytherapy with iodine 125, separately or combined. Five patients died; the causes were secondary tumors in two children, tumor recurrence in one, sepsis secondary to respiratory and urinary tract infections in the child with Down syndrome, and finally, hydrocephaly due to hyperproteinorachia of tumor origin in one. Average survival was 89 months. CONCLUSION: Chemotherapy and brachytherapy are therapeutic methods to be considered, especially in children under 5. Marsupialization of the residual cyst into the ventricular system postradio or oncolytic treatment through endoscopic or stereotactic techniques is useful in the treatment of endocranial hypertension and/or hypothalamic compression in these patients.

Child↗