Investigating changes in axonal density and morphology of glaucomatous optic nerves using fixel-based analysis

Background: Leukemia is the most common pediatric malignancy. Central Nervous System (CNS) is the most frequently involved extramedullary location at diagnosis and at relapse. </P><P> Objective: To determine if Magnetic Resonance Imaging (MRI) findings of optic nerves should contribute to early detection of CNS relapse in pediatric leukemia. Methods: Twenty patients (10 boys, 10 girls; mean age 8,3 years, range 4-16 years) with proven CNS relapse of leukemia followed up between 2009 and 2017 in our institution were included. Orbital MRI exams performed before and during CNS relapse were reviewed retrospectively. Forty optic nerves with Optic Nerve Sheaths (ONS) and Optic Nerve Heads (ONH) were evaluated on fat-suppressed T2-weighted TSE axial MR images. ONS diameter was measured from the point 10 mm posterior to the globe. ONS distension and ONH configuration were graded as 0, 1 and 2. Results: Before CNS relapse, right mean ONS diameter was 4.52 mm and left was 4.61 mm which were 5.68 mm and 5.66 mm respectively during CNS relapse showing a mean increase of 25% on right and 22% on left. During CNS relapse, ONS showed grade 0 distension in 15%, grade 1 in 60%, grade 2 in 25% and ONH demonstrated grade 0 configuration in 70%, grade 1 in 25% and grade 2 in 5% of the patients. Conclusion: MRI findings of optic nerves may contribute to diagnose CNS relapse by demonstrating elevated intracranial pressure in children with leukemia.

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Correlation Between DTI Findings and Volume of Corpus Callosum in Children with AUTISM

Current Medical Imaging Formerly Current Medical Imaging Reviews ◽

10.2174/1573405614666181005114315 ◽

2019 ◽

Vol 15 (9) ◽

pp. 895-899 ◽

Cited By ~ 1

Author(s):

Hafize Otcu Temur ◽

Ismail Yurtsever ◽

Gozde Yesil ◽

Rasul Sharifov ◽

Fatih Temel Yilmaz ◽

...

Keyword(s):

Corpus Callosum ◽

Cortical Neurons ◽

Diffusion Tensor ◽

Children With Autism ◽

Autism Spectrum ◽

Children With Asd ◽

Volume Measurements ◽

Adc Values ◽

Axonal Density ◽

Area And Volume

Background: Autism Spectrum Disorder (ASD) is a complex developmental disorder in which neurological basis is largely unknown. The Corpus Callosum (CC) is the main commissure that connects the cerebral hemispheres. Previous evidence suggests the involvement of the CC in the pathophysiology of autism. Aim: The aim of our study is to assess whether there were any changes in Corpus Callosum (CC) area and volume and to reveal the relationship between Diffusion Tensor Imaging (DTI) features in genu and splenium of corpus callosum in children with ASD. Methods: Eighteen patient and 15 controls were recruited. The volumetric sagittal TI images were used to provide measurements of midsagittal corpus callosum surface area while FA, MD, RD, and ADC values were extracted from genu and splenium of corpus callosum after which the correlation in the area and volume in ASD children was examined. Results: CC area and volume in children with ASD were decreased than controls. FA values obtained from the genu and splenum of CC were significantly lower and RD values were significantly higher. A positive correlation was observed between the FA of the genu and splenium and area and volume of the CC. There was a negative correlation between ADC, MD and RD of CC and area and volume measurements. Conclusion: The conclusions in the interrelations of morphometric and DTI data may demonstrate a likelihood of damages in the axons and cortical neurons. The results showed that there existed microstructural damages from the DTI findings. Furthermore, the decrease in FA could be a representation of the reduction in the myelination in nerve pathways, impaired integrity, reduced axonal density, and organization. Indeed, the changes in volumetric and microstructural of CC could be useful in evaluating underlying pathophysiology in children with autism.

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Novel in vivo depiction of optic nerves hemorrhages in child abuse: a 3D-SWI pilot study

Neuroradiology ◽

10.1007/s00234-020-02622-6 ◽

2021 ◽

Author(s):

Giulio Zuccoli

Keyword(s):

Optic Nerve ◽

Mass Effect ◽

Abusive Head Trauma ◽

Superficial Siderosis ◽

Susceptibility Artifacts ◽

Female Ratio ◽

Optic Nerves ◽

Statistical Correlations ◽

Post Traumatic

Abstract Purpose Until now, the diagnosis of optic nerves hemorrhages in abusive head trauma (AHT) has been obtained only in the postmortem setting. The aim of the IRB-approved study was to assess the presence of optic nerves hemorrhages in AHT patients using 3D-SWI. Methods Thirteen children with a final confirmed multidisciplinary diagnosis of AHT underwent coronal and axial 3D-SWI imaging of the orbits. The presence of optic nerve sheath (ONS) hemorrhages was defined by thickening and marked 3D-SWI hypointensity of the ONS, resulting in mass effect upon the CSF space. Optic nerve (ON) hemorrhages were defined by areas of susceptibility artifacts in the ON parenchyma. Superficial siderosis was defined by susceptibility artifact coating the ON. Furthermore, data about post-traumatic deformity of the ONS at the head of the optic nerve were collected. Results The average age of the population was 7.9 ± 5.9 months old. The average GCS was 11.8 ± 4.5. The male to female ratio was 7:6. ONS hemorrhages were identified in 69.2% of cases. Superficial siderosis and ON hemorrhages were identified in 38.5 and 76.9% of cases, respectively. 3D-SWI also depicted traumatic deformity of the ONS at the level of the optic nerve head in 10 cases (76.9%). No statistical correlations were identified between RetCam findings and 3D-SWI findings or GCS and ON hemorrhages. Conclusion This research shows that dedicated MRI with volumetric SWI of the orbits can depict hemorrhages in the ON, ONS, and ONS injury, in AHT victims.

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Validation of Deep-Learning Based Auto-segmentation of the Lens, Optic Nerves, and Chiasm for Stereotactic Radiosurgery

International Journal of Radiation Oncology*Biology*Physics ◽

10.1016/j.ijrobp.2020.07.250 ◽

2020 ◽

Vol 108 (3) ◽

pp. e784-e785

Author(s):

K. Salari ◽

E. Porter ◽

R. Levitin ◽

Z.A. Siddiqui ◽

A. Thompson ◽

...

Keyword(s):

Deep Learning ◽

Stereotactic Radiosurgery ◽

Optic Nerves

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Giant cell arteritis mimicking infiltrative leptomeningeal disease of the optic nerves

BMJ Case Reports ◽

10.1136/bcr-2014-209160 ◽

2015 ◽

Vol 2015 (apr09 1) ◽

pp. bcr2014209160-bcr2014209160 ◽

Cited By ~ 3

Author(s):

M. D. Kornberg ◽

J. N. Ratchford ◽

R. M. Subramaniam ◽

J. C. Probasco

Keyword(s):

Giant Cell Arteritis ◽

Giant Cell ◽

Leptomeningeal Disease ◽

Optic Nerves

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In vitro analysis of the origin and maintenance of O-2Aadult progenitor cells.

The Journal of Cell Biology ◽

10.1083/jcb.116.1.167 ◽

1992 ◽

Vol 116 (1) ◽

pp. 167-176 ◽

Cited By ~ 93

Author(s):

D Wren ◽

G Wolswijk ◽

M Noble

Keyword(s):

Adult Life ◽

Cell Types ◽

Adult Rats ◽

Optic Nerves ◽

Limited Life ◽

Old Rats ◽

Vitro Analysis

We have been studying the differing characteristics of oligodendrocyte-type-2 astrocyte (O-2A) progenitors isolated from optic nerves of perinatal and adult rats. These two cell types display striking differences in their in vitro phenotypes. In addition, the O-2Aperinatal progenitor population appears to have a limited life-span in vivo, while O-2Aadult progenitors appear to be maintained throughout life. O-2Aperinatal progenitors seem to have largely disappeared from the optic nerve by 1 mo after birth, and are not detectable in cultures derived from optic nerves of adult rats. In contrast, O-2Aadult progenitors can first be isolated from optic nerves of 7-d-old rats and are still present in optic nerves of 1-yr-old rats. These observations raise two questions: (a) From what source do O-2Aadult progenitors originate; and (b) how is the O-2Aadult progenitor population maintained in the nerve throughout life? We now provide in vitro evidence indicating that O-2Aadult progenitors are derived directly from a subpopulation of O-2Aperinatal progenitors. We also provide evidence indicating that O-2Aadult progenitors are capable of prolonged self renewal in vitro. In addition, our data suggests that the in vitro generation of oligodendrocytes from O-2Aadult progenitors occurs primarily through asymmetric division and differentiation, in contrast with the self-extinguishing pattern of symmetric division and differentiation displayed by O-2Aperinatal progenitors in vitro. We suggest that O-2Aadult progenitors express at least some properties of stem cells and thus may be able to support the generation of both differentiated progeny cells as well as their own continued replenishment throughout adult life.

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