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PubMed2004

Neurofibromatosis type 1 and optic pathway gliomas: follow-up of 54 patients.

OBJECTIVE: To describe the natural history of optic pathway gliomas (OPGs) in patients with neurofibromatosis type 1 (NF1), and to evaluate the current recommended guidelines for monitoring and follow-up of OPGs in this population. DESIGN: Retrospective case series. PARTICIPANTS: Patients with OPGs and NF1 seen in the neurofibromatosis clinic at the Children's Hospital at Westmead in Sydney, Australia. METHODS: Patients with definite NF1 and confirmed OPGs were identified and their medical records searched to obtain data on demographics, details of the OPG diagnosis, and serial ophthalmic examination findings. Patients were stratified into groups according to age and mode of presentation. MAIN OUTCOME MEASURES: Visual acuity was recorded for each eye and grouped into mild (Snellen equivalent > or = 6/12), moderate (Snellen equivalent = 6/15-6/60), and severe (Snellen equivalent < 6/60) visual impairment at time of diagnosis, during follow-up, and at the most recent examination. RESULTS: Data were collected on 54 patients, the majority of whom (78%) were seen from 1990 to 2002, with an average follow-up of 8.6 years. The mean age at the time of OPG diagnosis was 5.2 years, with 32 patients having symptoms or signs at the time of diagnosis. Seventeen patients were diagnosed after the age of 6 years (range, 7-15). Twenty-two patients had tumor progression within 1 year of diagnosis, and a further 6 patients showed progression after 1 year. Most patients' conditions were managed conservatively (68.5%). At follow-up, 17 patients (31.5%) had severe visual impairment (<6/60 Snellen equivalent) in their worse eye, and 16.7% had bilateral moderate/severe visual impairment. CONCLUSIONS: Contrary to some previous reports, our results show that OPGs in patients with NF1 often present in older children and may progress some time after diagnosis. Given the potential for serious visual consequences, these findings indicate a need for regular ophthalmological monitoring of this population for a long duration.

Adolescent↗

PubMed2003

Do children with optic pathway tumors have an increased frequency of other central nervous system tumors?

We questioned whether children with optic pathway tumors (OPTs) have an increased frequency of other CNS tumors on the basis of experience with a number of such children treated at our institution. The medical records of all patients with OPTs treated at Golisano Children's Hospital at Strong at the University of Rochester from 1957 to 2000 were reviewed to determine the incidence of additional CNS tumors in these children and whether the occurrence of these other CNS tumors is associated with any risk factors. Twenty-six children had OPTs. Twelve of the 26 children had biopsy-proved tumors; the remaining 14 were diagnosed on the basis of CT or MRI scans. Eight of the 26 patients (31%) had a total of 11 additional CNS tumors. (One child had 2 additional CNS neoplasms, and a second child had 3.) Nine were biopsy proved (3 glioblastoma, 3 anaplastic astrocytoma, 3 low-grade astrocytoma), and 2 were diagnosed by imaging studies alone (acoustic neuromas). Eight of the 11 tumors occurred at a median of 5 years (0.8-25 years) subsequent to the diagnosis of the OPTs; 3 were diagnosed simultaneously with the OPT. Of the 17 children with neurofibromatosis (NF) and OPTs, 8 (47%) had additional CNS tumors, while none of the 9 children (0%) without NF had other CNS tumors (P = 0.023). There was no association between radiation treatment of the primary OPT and subsequent development of other CNS tumors in the group as a whole, or when the analysis was confined to children with NF. Despite this lack of statistical association, all 7 CNS tumors that occurred following radiation arose in irradiated areas. The risk of simultaneous or subsequent CNS tumors in children with NF and OPTs is high. These children should be closely monitored for the simultaneous or subsequent occurrence of other CNS tumors.

Central Nervous System Neoplasms↗

PubMed1975

Dynamic properties of axonal transport of proteins and glycoproteins: a study based on the effects of metaphase blocking drugs in the developing optic pathway of chick embryos.

Some properties of the axonal transport of proteins and glycoproteins along the optic pathway of chick embryos and newly hatched chicks were studied by labelling retinal ganglion cells with 3H-proline or 3H-fucose. A study of the effects of colchicine (COL) and vinblastine (VLB) on embryonic axonal transport was also carried out. Marked changes in the efficiency of axonal transport were found throughout development. In particular, the fraction of retinal ganglion cell proteins which is rapidly exported toward tectal terminals increases during embryonic life but steadily decreases after hatching. Glycoprotein transport behaves similarly except that its efficiency is relatively higher at stages when critical events of synaptic maturation in the tectum are reported to occur. Embryonic axonal transport is blocked by COL and VLB at very low intravitreal concentrations. Retinal protein synthesis and the morphology of ganglion cells are profoundly altered by the drugs: in general, COL and VLB effects were much more marked in embryonic than in mature neurons. An analysis of the time course of rapid transport along embryonic optic axons was carried out by reducing the efflux of labelled proteins from the eye by giving VLB intravitreally 2 h after the pulse. It revealed some peculiar features in the retino-tectal migration of glycoproteins and confirmed their progressive accumulation within terminals as previously described by radioautography. These results suggest that axonal transport of proteins during embryonic life undergoes changes in parallel with synaptic maturation. It may thus be considered as one of the factors controlling the genesis of neuronal networks.

Animals↗

PubMed1991

Detection of optic pathway misrouting in the human albino neonate.

The diagnosis of albinism is indicated by the presence of visual pathway misrouting in which temporal retinal fibers erroneously decussate at the optic chiasm disrupting the normal topographical distribution of retinal geniculate-cortical projections. Detection of misrouted fibers is effected by non-invasive electrophysiological assessment of the topographical representation of the visual evoked potential (VEP) following full field monocular stimulation. By combining appropriate state defined neonatal recording procedures with the albino VEP test paradigm, the presence of aberrant optic pathway projections was detected in a five-day-old full-term infant. The electrophysiological signature pathognomonic to albinism was observed within a long (300 ms) latency window of an otherwise normal neonatal luminance flash response. The results of this study indicate that the VEP misrouting test can be extended to reliable albino diagnosis within the neonatal period.

Albinism↗

PubMed1976

Action of chloroquine on in vivo RNA and protein biosynthesis in the retina and the optic pathway of the rabbit.

The in vivo action of chloroquine on RNA and protein metabolism in the optic pathway of the albino or pigmented rabbit was examined. To study the acute effects, chloroquine in a dose of 500 mug was injected into the vitreous body of one eye. The following day the animals were injected into both eyes with [3H]uridine or [3H]leucine. At various time intervals following the isotope injections the retinal synthesis and the axonal transport of labelled RNA or protein was studied. The results showed no significant difference between the drug-treated and the control side with respect to synthesis and axonal transport of RNA or protein. Nor was any selective effect noticed on the synthesis of different RNA fractions from the retina. In long-term experiments chloroqune (100 mg/kg body weight) was administered via their drinking water 3 days a week for a period of 6 or 8 months. Following an intraocular injection of [3H]leucine no significant change in rapid axonal transport could be found in those chronically treated rabbits.

Animals↗

PubMed2026

Long-term outcomes after a randomized phase II trial of nerve growth factor eye drops for optic pathway gliomas: four-year follow-up findings in children.

PURPOSE: A previous double-blind, randomized, placebo-controlled, phase II clinical trial reported beneficial effects of a short-term treatment (10 days) with murine nerve growth factor (mNGF) eye drops on visual function in children with optic pathway gliomas (OPG). The present study aimed to evaluate long-term changes in clinical and neuroradiological parameters in the cohort of OPG patients who had previously participated in the phase II mNGF trial. METHODS: Fifteen of the 18 patients originally enrolled in the phase II mNGF trial agreed to undergo clinical and neuroradiological monitoring over a 48-month follow-up period. Of these, 9 had originally been randomized to mNGF and 6 to placebo; no additional treatment (mNGF, chemotherapy, or radiotherapy) was administered during the extended follow-up. Every 6 months, patients underwent general clinical and neuro-ophthalmological examination, visual evoked potentials (VEP), and photopic negative response of the electroretinogram (PhNR). Brain MRI was performed every 12 months. RESULTS: Comparison of initial and final follow-up median values revealed no statistically significant changes in visual acuity, VEP amplitude, PhNR amplitude, or visual field radius. No significant differences were observed in any parameter relative to baseline values of the mNGF trial. Brain MRI demonstrated stable disease in all patients throughout the observation period. CONCLUSION: These findings, obtained in an observational extension of the original randomized cohort, indicate favorable long-term safety and tolerability of a short-term course of topical mNGF in children with OPG, with sustained visual and neuroradiological stability over four years, rather than evidence of persistent treatment efficacy. Further prospective, adequately powered and randomized clinical studies are needed to confirm both the short- and long-term clinical efficacy of NGF treatment in preventing OPG-induced visual loss.

Humans↗

PubMed1994

Natural history of optic pathway tumors in children with neurofibromatosis type 1: a longitudinal study.

To assess the natural history of optic pathway tumors (OPT) in children with neurofibromatosis type 1 (NF-1), from January 1985 through May 1993 we performed a prospective, longitudinal study of OPT in an unselected population of children with NF-1. Of 227 children with NF-1 seen in a specialty clinic, 176 (77%) underwent neuroimaging. Children in whom tumors were identified were followed closely by both repeated neuroimaging and ophthalmologic examinations to detect tumor growth or visual deterioration. Thirty-three children (19%) were found to have OPT at a median age of 4.2 years. The median age of children who had ophthalmologic complaints was significantly lower than that of children who had no such complaints (1.9 vs 5.3 years; p < 0.001). Although eight tumors were discovered because of ophthalmologic complaints or evidence of precocious puberty, 25 children (76%) were free of symptoms at the time of diagnosis. Twenty-one children (64%) had normal ophthalmologic findings at diagnosis; six children, all with chiasmal tumors, had previously unrecognized decreased visual acuity. Only three children (9%) had evidence of either tumor growth or deteriorating vision after diagnosis; the median duration of neuroimaging follow-up was 2.4 years (range, 0.2 to 7.2 years) and of ophthalmologic examinations 3.4 years (range, 0.2 to 8.1 years). All symptomatic OPT were diagnosed before 6 years of age. We conclude that OPT rarely progress during the next few years in children with NF-1 once the OPT have been discovered. The utility of screening neuroimaging for OPT in symptom-free children with NF-1 appears very limited.

Adolescent↗

PubMed1988

Calcium-dependent evoked release of N-[3H]acetylaspartylglutamate from the optic pathway.

N-Acetylaspartylglutamate (NAAG) is a neuropeptide localized to several putative glutamatergic neuronal systems, including the rodent optic pathway. To determine whether the peptide is released by depolarization, the superior colliculus of the rat was perfused with 2 microCi of [3H]NAAG, then with Krebs-bicarbonate buffer for 1 h, using a microdialysis system. Subsequently, 10-min fractions were collected and analyzed by HPLC for [3H]NAAG. Addition of 100 microM veratridine resulted in a several-fold increase in the evoked release of [3H]NAAG that was virtually abolished by coperfusion with Ca2+-free Krebs buffer containing 1 mM EGTA. When [3H]glutamate was used as the precursor, veratridine depolarization resulted in only an 80% increase in the release of [3H]NAAG. Prior enucleation of the right eye reduced the spontaneous release of [3H]NAAG by 50%, and the veratridine-evoked release by greater than 85%, from the left superior colliculus. These results suggest that NAAG is released upon depolarization and may serve as a neurotransmitter/neuromodulator in the optic tract.

Animals↗

PubMed1998

Long-term follow up of 69 patients treated for optic pathway tumours before the chemotherapy era.

AIM: To analyse the long-term results of conservative management with radiotherapy in patients with optic pathway tumours. DESIGN: All 69 patients were symptomatic at diagnosis and most neoplasms involved the optic chiasm and hypothalamus. RESULTS: At 10 years, overall survival and progression free survival were 83% and 65.5%, respectively. After radiotherapy, vision improved in 18 patients and remained stable in 29 other patients. Cerebrovascular complications occurred in nine of 53 patients treated with radiotherapy after a median interval of two and a half years. These complications were five times more frequent in patients with neurofibromatosis type 1 (NF1). Severe intellectual disabilities were present in 18 children, most of whom underwent irradiation at a very young age (median age, 4 years). IMPLICATIONS: Radiotherapy is a valuable treatment in terms of tumour response, visual outcome, and progression free survival. However, in young children and in patients with NF1, major sequelae are encountered and new treatment strategies should be proposed for these patients.

Adolescent↗

PubMed2026

Screening for neurofibromatosis type 1-related optic pathway gliomas: a systematic review.

BACKGROUND: Neurofibromatosis-type 1 (NF1) is a genetic disorder characterized by developing optic pathway gliomas (OPGs) in 15%-20% of patients with higher estimates where consanguinity is prevalent. Clinically, NF1-OPG might be unpredictable with the risk of OPG progression and visual impairment. The optimal time for screening is controversial. We aim to identify the mean/median age at diagnosis of NF1-OPG and its clinical spectrum. METHODS: A systematic review of PubMed, Web of Science, and Embase databases was conducted for English-language publications from January 1993 to October 2025, exploring the visual screening of OPGs in NF1 patients, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and registered in the Prospective Register of Systematic Reviews (PROSPERO ID: CRD420251036244). Inclusion criteria focused on studies reporting the age at OPG diagnosis and visual manifestations in NF1 patients. Data were extracted on demographics, age at NF1 and OPG diagnosis, tumour location (using the Dodge classification), and presenting symptoms. Sixteen studies met the inclusion criteria. RESULTS: Among 4 739 NF1 patients, 818 had OPGs, with prevalence ranging from 4.2% to 46.7%. The age at NF1 diagnosis ranged from 0 to 132 months (mean: 18-38 months), and at OPG diagnosis from 0-240 months (median: 29-58 months). Approximately 58.4% of OPGs were asymptomatic, and 25% were above the age of 5 years. Among symptomatic patients, the most frequent presentations included decreased visual acuity (62%), abnormal optic disc (45%), proptosis (20%), strabismus (12%), and visual field defects (7%). CONCLUSIONS: NF1-related OPGs typically present early within 6 years of age. Early ophthalmologic and/or radiologic screening at the time of NF1 diagnosis enhances the detection of silent OPGs.

Humans↗

PubMed1998

Potential prognostic factors of relapse-free survival in childhood optic pathway glioma: a multivariate analysis.

There is still no consensus on the natural history and optimal management of optic pathway gliomas (OPG) in children. In order to tackle optimal management issues, we need to clearly understand the prognostic and confounding factors affecting relapse of OPG. We propose the use of the Cox proportional hazards (PH) model in a retrospective study of childhood OPG of 69 children seen from 1977 to 1994. We have developed a comprehensive model capable of multivariate analyses and handling time-dependencies. Our studies showed that relapse-free survival improves with increasing age, the presence of neurofibromatosis 1 (NF1), and chemotherapy and radiotherapy (p < 0.0005). Sex, tumor position and surgery do not significantly affect survival. Older children with NF1 have extremely good prognosis. We noted behavior that departs from the strictly proportional hazards model, but results were inconclusive.

Adolescent↗

PubMed1990

Calpain and calpastatin activity in the optic pathway.

The levels of the neutral proteolytic enzymes calpains and their endogenous inhibitor calpastatin were determined in the retina and in the retrobulbar optic pathway in the albino rabbit. The highest level of calpains was observed in the optic nerve with decreasing levels in the optic tract and superior colliculus. The level of calpastatin in the retina was very low compared to that in the optic nerve and tract and other parts of the nervous system.

Animals↗

PubMed1994

Orbital and optic pathway sarcoidosis: MR findings.

PURPOSE: To identify and characterize the MR findings of sarcoidosis when it involves the orbit and visual pathways. METHODS: The MR scans of 15 patients, 3 with presumed and 12 with proved orbital or optic pathway sarcoidosis were retrospectively reviewed. RESULTS: Eight patients had MR evidence of optic nerve involvement by sarcoid granuloma. Perineural enhancement was seen in four cases, optic atrophy in one. Three who had had unenhanced scans showed optic nerve enlargement. Nine patients had optic chiasmal involvement. One patient had increased T2 signal in the optic radiations. Three patients had orbital masses that had MR signal characteristics similar to pseudotumor. Five patients had periventricular white matter abnormalities closely resembling multiple sclerosis. CONCLUSIONS: Sarcoidosis should be considered in the differential diagnosis of optic nerve or nerve sheath enhancement on MR. Orbital sarcoidosis has MR characteristics very similar to pseudotumor.

Adolescent↗

PubMed1986

Map of retinal position onto the cross section of the optic pathway of goldfish.

The position of a retinal cell is defined by the two polar coordinates: r, the distance from the optic disc, and theta, the angular (or clock-face) position. Axons of similar theta value were labeled by the punctate application of horseradish peroxidase (HRP) to optic axons in the retina, and axons of similar r-value were labeled by the application of this same marker to a tectal fascicle. Labeled axons were traced in serial transverse sections of the optic pathway from the retina to the tectum to learn the map of the retinal surface onto the cross section of the pathway. Retinas were flat-mounted and treated for HRP to show the retinal origins of the labeled axons. Axons of similar r were clustered together, and the fraction of the pathway's cross-sectional area occupied by the cluster was about the same as the fraction of the retinal area occupied by the group of labeled somata. Axons of similar theta were also clustered, but the fraction of the cross-sectional area they occupied was larger than the fraction of retinal area occupied by their somata. The geometry of the clusters of labeled axons depended on the proximodistal location in the pathway. Near the retina both were strip-shaped, but the location and orientation of the strip varied. Both an r-strip and a theta-strip were labeled in some pathways by dual applications of HRP; the two strips were mutually orthogonal at all levels. Each of r and theta mapped onto a separate axis. The axons from most peripheral retina (largest r) were everywhere adjacent to the pia, and axons of progressively more central retina (smaller r) were progressively more separated from the pia (except in the nerve, where the secondary fasciculation complicates the geometry by wrapping old axons in new pia). The map of the circular variable, theta, onto a line, required a discontinuity, the location of which differed, depending on the proximodistal level. From the retina to the chiasm, the discontinuity was at the ventral retinal radius (i.e., the right retinal clock-face positions were ordered 6-9-12-3-6 o'clock across the line); just central to the chiasm, the fibers reordered to put the discontinuity at the nasal radius (clock-face positions ordered 3-6-9-12-3); at the brachial bifurcation, the 3-6-9 half turned dorsally, the 9-12-3 half, ventrally.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

PubMedDate not supplied

The early evolution of neurofilamentous accumulations due to 2,5-hexanediol in the optic pathways of the rat.

Rats were given 2,5-hexanediol in their water for more than 5 weeks. The changes in the optic pathways were studied both qualitatively and quantitatively. Increase in 10-nm filaments within axons was noticeable from 10 days onwards in the superior colliculus and in the brachium of the superior colliculus. From then onwards there was a steady increase in the number of affected axons, and their gross enlargement occurred. The proportion of affected fibres in the brachia was in fact few, but all fibres were of retinotectal origin. Less than half of those in the superior colliculus that were swollen were of retinal origin. Measurement of axon diameter versus myelin sheath thickness showed gross relative thinning of the latter. Axon degeneration did not occur but there was increasing ultrastructural evidence of impairment of transport of organelles both centrifugally and centripetally as the filamentous masses accumulated.

Animals↗

PubMed1998

Maturational changes in cell surface antigen expression in the mouse retina and optic pathway.

The distribution of the cell surface molecules M6 and L1 was studied using the immunohistochemistry and in situ hybridization in the developing and adult mouse retina and optic nerve. L1 is a cell adhesion molecule while M6 is a cell surface molecule homologous to the myelin protein proteolipid protein (PLP/DM20). Although both molecules were expressed in retina and optic nerves of embryonic and neonatal mice, our studies show that their patterns of postnatal expression are quite different. While L1 continues to be expressed in optic axons throughout adulthood, expression of M6 on optic axons declines after birth and instead becomes strongly expressed on Müller glial endfeet and in the inner plexiform layer. The modulation of these molecules after birth could provide clues to changing cell-cell interactions occurring in the proximal portion of the optic pathway.

Animals↗

PubMedDate not supplied

Cavernous hemangioma of the intracranial optic pathways: CT and MRI.

PURPOSE: The purpose of this work was to describe the CT and MR findings in three patients with cavernous hemangioma (CH) of the intracranial optic pathways. METHOD: CT and MR studies of three patients with CH of the optic chiasm were reviewed. All patients underwent MRI of the chiasmal area, with coronal T2- and T1-weighted studies as well as gadolinium-enhanced coronal and sagittal T1-weighted studies. RESULTS: The patients (mean age, 40 years) presented with chiasmal apoplexy (two cases) and progressive decrease of visual acuity (one case). In all cases, MRI showed regular enlargement of the optic chiasm, with extension to the optic nerve in one case and to the left optic tract in one case. The chiasmatic dimension was 2.5-3 cm in two cases and 1-1.5 cm in the other case. In all cases, MRI revealed an acute (isointense signal on T1-weighted and hypointense signal on T2-weighted sequences) or subacute (hyperintense signal on T1 - and T2-weighted sequences) hemorrhage with, adjacent to it, an area with signals of blood of different ages, highly suggestive of CH. CT showed, in chiasmatic CHs, a suprasellar mass spontaneously denser than adjacent brain parenchyma. In two cases, microcalcifications were associated. In two cases, CT and MRI revealed slight heterogeneous enhancement after contrast agent administration. In one case, no enhancement was observed. Two patients underwent surgery by frontopterional craniotomy. The optic chiasms were swollen with an intrinsic bluish mass. The cerebrospinal fluid was not xanthochromic. Microscope examination confirmed the diagnosis of CH. After 12 months, the operated patients had improved visual acuity and visual field but did not completely recover. The nonoperated patient (because of spontaneous rapid recovery of visual acuity) was followed clinically and on MRI over 18 months. CONCLUSION: CH in the optic chiasm must be suspected in the presence of an acute chiasmatic syndrome. MRI is the best imaging modality, showing either an acute or a subacute chiasmatic hemorrhage or the typical pattern of CH with heterogeneous alternation of foci of blood of different ages, with a central focus of methemoglobin, a peripheral rim of hemosiderin, adjacent foci of acute or subacute hemorrhage, and slight or no enhancement after gadolinium administration.

Adult↗

PubMed2002

A patient with optic pathway glioma, scoliosis, Chiari type I malformation and syringomyelia: is it Neurofibromatosis type 1?

A 22 years old girl had features of optic pathway glioma, scoliosis, Chiari type 1 malformation and cervical syringomyelia. She had no cutaneous lesions. We considered this combination to be more than coincidental and argue in favour of considering the case as a variant form of Neurofibromatosis type 1. The relevent literature in favour of our contention has been reviewed.

Adult↗