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Current Opinion in Ophthalmology Sep 2019Optic pathway gliomas are low-grade neoplasms that affect the precortical visual pathway of children and adolescents. They can affect the optic nerve, optic chiasm,... (Review)
Review
PURPOSE OF REVIEW
Optic pathway gliomas are low-grade neoplasms that affect the precortical visual pathway of children and adolescents. They can affect the optic nerve, optic chiasm, optic tracts and radiations and can either be sporadic or associated with neurofibromatosis type one. Gliomas isolated to the optic nerve (ONG) represent a subgroup of optic pathway gliomas, and their treatment remains controversial. New developments in ONG treatment have emerged in recent years, and it is necessary for clinicians to have a current understanding of available therapies.
RECENT FINDINGS
The current review of the literature covers the background of and recent developments in ONG treatment, with a focus on standard chemotherapy, new molecularly targeted therapies, radiation therapy and surgical resection and debulking.
SUMMARY
Although standard chemotherapy remains the mainstay of ONG treatment, newer molecularly targeted therapies such as mitogen-activated protein kinase kinase inhibitors and bevacizumab represent a promising new treatment modality, and clinical studies are ongoing.
Topics: Adolescent; Antineoplastic Agents; Child; Female; Humans; Male; Molecular Targeted Therapy; Ophthalmologic Surgical Procedures; Optic Chiasm; Optic Nerve Glioma; Optic Nerve Neoplasms; Optic Tract; Radiotherapy
PubMed: 31246635
DOI: 10.1097/ICU.0000000000000587 -
ENeurologicalSci Sep 2021•A patient exhibited IgG4-related hypothalamo-hypophysitis.•Prominent high-signal areas of swelling were observed in the hypothalamus, tuber cinereum, infundibulum,...
•A patient exhibited IgG4-related hypothalamo-hypophysitis.•Prominent high-signal areas of swelling were observed in the hypothalamus, tuber cinereum, infundibulum, and bilateral optic nerve systems.•MRI T1WI with contrast media demonstrated enhanced neurohypophysis and cystic swelling, and compressed anterior pituitary.•MRI findings improved rapidly after 4 days of steroid therapy.
PubMed: 34466672
DOI: 10.1016/j.ensci.2021.100362 -
Science Translational Medicine Sep 2023Tau pathogenesis is a hallmark of many neurodegenerative diseases, including Alzheimer's disease (AD). Although the events leading to initial tau misfolding and...
Tau pathogenesis is a hallmark of many neurodegenerative diseases, including Alzheimer's disease (AD). Although the events leading to initial tau misfolding and subsequent tau spreading in patient brains are largely unknown, traumatic brain injury (TBI) may be a risk factor for tau-mediated neurodegeneration. Using a repetitive TBI (rTBI) paradigm, we report that rTBI induced somatic accumulation of phosphorylated and misfolded tau, as well as neurodegeneration across multiple brain areas in 7-month-old tau transgenic PS19 mice but not wild-type (WT) mice. rTBI accelerated somatic tau pathology in younger PS19 mice and WT mice only after inoculation with tau preformed fibrils and AD brain-derived pathological tau (AD-tau), respectively, suggesting that tau seeds are needed for rTBI-induced somatic tau pathology. rTBI further disrupted axonal microtubules and induced punctate tau and TAR DNA binding protein 43 (TDP-43) pathology in the optic tracts of WT mice. These changes in the optic tract were associated with a decline of visual function. Treatment with a brain-penetrant microtubule-stabilizing molecule reduced rTBI-induced tau, TDP-43 pathogenesis, and neurodegeneration in the optic tract as well as visual dysfunction. Treatment with the microtubule stabilizer also alleviated rTBI-induced tau pathology in the cortices of AD-tau-inoculated WT mice. These results indicate that rTBI facilitates abnormal microtubule organization, pathological tau formation, and neurodegeneration and suggest microtubule stabilization as a potential therapeutic avenue for TBI-induced neurodegeneration.
Topics: Animals; Mice; Brain Injuries, Traumatic; Microtubules; DNA-Binding Proteins; Brain; Alzheimer Disease; Disease Models, Animal; Excipients; Mice, Transgenic
PubMed: 37703352
DOI: 10.1126/scitranslmed.abo6889 -
Frontiers in Aging Neuroscience 2022To investigate the association between degeneration of retinal structure and shrinkage of the optic tract in patients after thalamic stroke.
OBJECTIVES
To investigate the association between degeneration of retinal structure and shrinkage of the optic tract in patients after thalamic stroke.
MATERIALS AND METHODS
Patients with unilateral thalamic stroke were included. Structural magnetic resonance imaging (MRI) and optical coherence tomography (OCT) were performed to obtain parameters of optic tract shrinkage (lateral index) and retina structural thickness (retinal nerve fiber layer, RNFL; peripapillary retinal nerve fiber layer, pRNFL; ganglion cell-inner plexiform layer, GCIP), respectively. Visual acuity (VA) examination under illumination was conducted using Snellen charts and then converted to the logarithm of the minimum angle of resolution (LogMAR). We investigated the association between LI and OCT parameters and their relationships with VA.
RESULTS
A total of 33 patients and 23 age-sex matched stroke-free healthy controls were enrolled. Patients with thalamic stroke showed altered LI compared with control participants ( = 0.011) and a significantly increased value of LI in the subgroup of disease duration more than 6 months ( = 0.004). In these patients, LI were significantly associated with pRNFL thickness (β = 0.349, 95% confidence interval [CI]: 0.134-0.564, = 0.002) after adjusting for confounders (age, sex, hypertension, diabetes, dyslipidemia, and lesion volume). LI and pRNFL were both significantly associated with VA in all patients (LI: β = -0.275, 95% CI: -0.539 to -0.011, = 0.041; pRNFL: β = -0.023, 95% CI: -0.046 to -0.001, = 0.040) and in subgroup of disease duration more than 6 months (LI: β = -0.290, 95% CI: -0.469 to -0.111, = 0.002; pRNFL: β = -0.041, 95% CI: -0.065 to -0.017, = 0.003).
CONCLUSION
Shrinkage of the optic tract can be detected in patients with thalamic stroke, especially after 6 months of stroke onset. In these patients, the extent of optic tract atrophy is associated with pRNFL thickness, and they are both related to visual acuity changes.
PubMed: 35966790
DOI: 10.3389/fnagi.2022.942438 -
Frontiers in Medicine 2022Optic tract lesions (OTL) are often difficult to diagnose. We suggest an algorithm to simplify the often-challenging diagnosis of OTL. Clinical and imaging data were...
Optic tract lesions (OTL) are often difficult to diagnose. We suggest an algorithm to simplify the often-challenging diagnosis of OTL. Clinical and imaging data were retrospectively collected from the electronic files of 6 patients diagnosed with OTL at a tertiary medical center in 2016-2020. The series included 4 children and 2 adults with an OTL caused by a glioma ( = 5) or motor vehicle accident ( = 1). Magnetic resonance imaging (MRI) revealed a suprasellar glioma involving the chiasm and tract alone (n = 1) and the ipsilateral optic nerve (n = 2) and only optic tract (3). Perimetry showed incongruent homonymous hemianopia in 3 patients. In two patients, perimetry could only be performed in one eye, and demonstrated hemianopia. In one patient perimetry was unreliable. Fundus examination revealed bow-tie atrophy in all patients. On optical coherence tomography (OCT) of the peripapillary retinal nerve fiber layer (RNFL) horizontal thinning was observed in the contralateral eye ( = 6). By presenting the information in a predefined order-visual field damage, OCT RNFL thickness, and MRI-the diagnosis could be easily reached even in children, and when other structures like the chiasm were involved. Fundus photographs easily detect bow tie atrophy in children. Systematic presentation of the data in a predefined order can ease the diagnostic process of OTLs.
PubMed: 36388882
DOI: 10.3389/fmed.2022.1029829 -
The Journal of Neuroscience : the... Aug 2022Individual differences among human brains exist at many scales, spanning gene expression, white matter tissue properties, and the size and shape of cortical areas. One...
Individual differences among human brains exist at many scales, spanning gene expression, white matter tissue properties, and the size and shape of cortical areas. One notable example is an approximately 3-fold range in the size of human primary visual cortex (V1), a much larger range than is found in overall brain size. A previous study (Andrews et al., 1997) reported a correlation between optic tract (OT) cross-section area and V1 size in postmortem human brains, suggesting that there may be a common developmental mechanism for multiple components of the visual pathways. We evaluated the relationship between properties of the OT and V1 in a much larger sample of living human brains by analyzing the Human Connectome Project (HCP) 7 Tesla Retinotopy Dataset (including 107 females and 71 males). This dataset includes retinotopic maps measured with functional MRI (fMRI) and fiber tract data measured with diffusion MRI (dMRI). We found a negative correlation between OT fractional anisotropy (FA) and V1 surface area ( = -0.19). This correlation, although small, was consistent across multiple dMRI datasets differing in acquisition parameters. Further, we found that both V1 surface area and OT properties were correlated among twins, with higher correlations for monozygotic (MZ) than dizygotic (DZ) twins, indicating a high degree of heritability for both properties. Together, these results demonstrate covariation across individuals in properties of the retina (OT) and cortex (V1) and show that each is influenced by genetic factors. The size of human primary visual cortex (V1) has large interindividual differences. These differences do not scale with overall brain size. A previous postmortem study reported a correlation between the size of the human optic tract (OT) and V1. In this study, we evaluated the relationship between the OT and V1 in living humans by analyzing a neuroimaging dataset that included functional MRI (fMRI) and diffusion MRI (dMRI) data. We found a small, but robust correlation between OT tissue properties and V1 size, supporting the existence of structural covariance between the OT and V1 in living humans. The results suggest that characteristics of retinal ganglion cells (RGCs), reflected in OT measurements, are correlated with individual differences in human V1.
PubMed: 35853720
DOI: 10.1523/JNEUROSCI.0043-22.2022