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Documenta Ophthalmologica. Advances in... Apr 2021To describe the trans-occipital asymmetries of pattern and flash visual evoked potentials (VEPs), in an infant with MRI findings of unilateral optic nerve aplasia and...
PURPOSE
To describe the trans-occipital asymmetries of pattern and flash visual evoked potentials (VEPs), in an infant with MRI findings of unilateral optic nerve aplasia and hemi-chiasm dysplasia.
METHODS
A child with suspected left cystic microphthalmia, left microcornea, left unilateral optic nerve aplasia, and hemi-chiasm underwent a multi-channel VEP assessment with pattern reversal, pattern onset, and flash stimulation at the age of 16 weeks.
RESULTS
There was no VEP evidence of any post-retinal visual pathway activation from left eye with optic nerve aplasia. The VEP trans-occipital distribution from the functional right eye was skewed markedly across the midline, in keeping with significant misrouting of optic nerve fibres at the chiasm. This was supported by the anatomical trajectory of the optic chiasm and tracts seen on MRI.
CONCLUSION
This infant has chiasmal misrouting in association with unilateral optic nerve aplasia and unilateral microphthalmos. Chiasmal misrouting has not been found in patients with microphthalmos or anophthalmos, but has been reported after early eye loss in animal models. Our findings contribute to our understanding of the discrepancy between the visual pathway physiology of human unilateral microphthalmia and animal models.
Topics: Electroretinography; Evoked Potentials, Visual; Humans; Infant; Optic Chiasm; Optic Nerve; Optic Nerve Diseases
PubMed: 32852652
DOI: 10.1007/s10633-020-09788-7 -
International Journal of Developmental... Feb 2014Developmental abnormalities of optic nerve are the leading cause of child blindness. The goal of this study was to use diffusion tensor imaging (DTI) to characterize the... (Review)
Review
Developmental abnormalities of optic nerve are the leading cause of child blindness. The goal of this study was to use diffusion tensor imaging (DTI) to characterize the optic nerve development of non-human primates during the normal maturation from birth to adulthood. Forty healthy rhesus monkeys aged from 2 weeks to 6 years old were scanned with a clinical 3T scanner. It was demonstrated that the DTI parameters followed an exponential pattern during optic nerve maturation. The time constants of mean diffusivity (MD), fractional anisotropy (FA), axial diffusivity (λ∥) and radial diffusivity (λ⊥) were 16, 14, 18 and 15 months in rhesus monkeys, respectively. Significant decrease in RD was observed firstly at 12 months after birth (p<0.05). No significant differences were observed between the left and right optic nerves in any age group. The in vivo imaging results reveal the normal evolution patterns of DTI parameters during optic nerve maturation in primates. The data might be used as a reference in the examination of optic nerve developmental abnormalities or injury in children or preclinical studies.
Topics: Analysis of Variance; Animals; Animals, Newborn; Anisotropy; Decision Making, Computer-Assisted; Diffusion Tensor Imaging; Macaca mulatta; Optic Nerve
PubMed: 23831120
DOI: 10.1016/j.ijdevneu.2013.06.007 -
Scientific Reports Dec 2017The association between corneal biomechanical properties and glaucoma is an area of much interest. We determined the relationship between corneal hysteresis (CH) and...
The association between corneal biomechanical properties and glaucoma is an area of much interest. We determined the relationship between corneal hysteresis (CH) and optic nerve parameters in healthy myopic subjects in the current study. CH was measured with Reichert Ocular Response Analyzer in 108 eyes from 108 healthy myopic subjects. All subjects received retinal nerve fiber layer and optic disc imaging Cirrus HD-OCT, GDx ECC, and Heidelberg Retina Tomograph II. None of the tested optic nerve parameters showed statistical significance with CH by using correlation analysis. For RNFL parameters, there was a negative but not statistically significant correlation between CH and average RNFL thickness obtained with OCT (r = -0.15, p = 0.13). For optic disc parameters, there was a negative but not statistically significant correlation between CH and rim area measured with OCT (r = -0.10, p = 0.29). The current study did not find any statistically significant relationship between CH and optic nerve parameters as measured by all three imaging modalities in healthy myopic eyes. Therefore, the relationship observed previously in glaucoma subjects is likely coming to fruition as optic nerve damage is caused by the disease.
Topics: Adolescent; Adult; Biomechanical Phenomena; Cornea; Female; Humans; Male; Myopia; Optic Nerve; Organ Size; Young Adult
PubMed: 29235544
DOI: 10.1038/s41598-017-15386-6 -
Scientific Reports Jun 2022The study investigated clinical features of sellar and suprasellar tumors with optic nerve bending. Twenty-five patients (13 men/12 women; age, 59.0 ± 12.9 years)...
The study investigated clinical features of sellar and suprasellar tumors with optic nerve bending. Twenty-five patients (13 men/12 women; age, 59.0 ± 12.9 years) with optic nerve bending in one eye who underwent tumor resection for sellar and suprasellar tumors were included. The other eye, without optic nerve bending, was the control. The pre- and postoperative best-corrected visual acuity (BCVA) and ganglion cell layer (GCL) + inner plexiform layer (IPL) thickness were studied retrospectively using optical coherence tomography. Preoperative BCVA in the eye with optic nerve bending was significantly poor and improved significantly after tumor resection. Eyes with optic nerve bending had significantly less GCL + IPL thickness on the temporal side than eyes without optic nerve bending. Preoperative GCL + IPL thickness of the entire macula was reduced in eyes with optic nerve bending and poor postoperative BCVA compared to those with good postoperative BCVA. There was no significant difference in GCL + IPL thickness of eyes with optic nerve bending before and after tumor resection. Optic nerve bending caused by sellar and suprasellar tumors resulted in visual impairment and decreased retinal ganglion cells. Eyes with optic nerve bending and severely reduced GCL + IPL thickness may have less BCVA improvement after tumor resection.
Topics: Aged; Female; Humans; Male; Middle Aged; Neoplasms; Optic Nerve; Retinal Ganglion Cells; Retrospective Studies; Tomography, Optical Coherence; Visual Acuity
PubMed: 35773336
DOI: 10.1038/s41598-022-15381-6 -
JAMA Network Open Jun 2020
Topics: Diagnosis, Differential; Humans; Optic Nerve; Papilledema
PubMed: 32484550
DOI: 10.1001/jamanetworkopen.2020.7159 -
Investigative Ophthalmology & Visual... Aug 2017The eye and its accessory structures, the optic nerve and the extraocular muscles, form a complex dynamic system. In vivo magnetic resonance imaging (MRI) of this system...
PURPOSE
The eye and its accessory structures, the optic nerve and the extraocular muscles, form a complex dynamic system. In vivo magnetic resonance imaging (MRI) of this system in motion can have substantial benefits in understanding oculomotor functioning in health and disease, but has been restricted to date to imaging of static gazes only. The purpose of this work was to develop a technique to image the eye and its accessory visual structures in motion.
METHODS
Dynamic imaging of the eye was developed on a 3-Tesla MRI scanner, based on a golden angle radial sequence that allows freely selectable frame-rate and temporal-span image reconstructions from the same acquired data set. Retrospective image reconstructions at a chosen frame rate of 57 ms per image yielded high-quality in vivo movies of various eye motion tasks performed in the scanner. Motion analysis was performed for a left-right version task where motion paths, lengths, and strains/globe angle of the medial and lateral extraocular muscles and the optic nerves were estimated.
RESULTS
Offline image reconstructions resulted in dynamic images of bilateral visual structures of healthy adults in only ∼15-s imaging time. Qualitative and quantitative analyses of the motion enabled estimation of trajectories, lengths, and strains on the optic nerves and extraocular muscles at very high frame rates of ∼18 frames/s.
CONCLUSIONS
This work presents an MRI technique that enables high-frame-rate dynamic imaging of the eyes and orbital structures. The presented sequence has the potential to be used in furthering the understanding of oculomotor mechanics in vivo, both in health and disease.
Topics: Adult; Eye; Eye Movements; Female; Healthy Volunteers; Humans; Image Processing, Computer-Assisted; Magnetic Resonance Imaging; Male; Ocular Physiological Phenomena; Oculomotor Muscles; Optic Nerve; Retrospective Studies
PubMed: 28813574
DOI: 10.1167/iovs.17-21861 -
The British Journal of Ophthalmology May 1998Three separate experimental models of optic nerve regeneration have been presented--along the existing pathway in the presence of antibodies to neutralise inhibitory... (Review)
Review
Three separate experimental models of optic nerve regeneration have been presented--along the existing pathway in the presence of antibodies to neutralise inhibitory molecules, along peripheral nerve grafts and from retinal transplants. Each offers a theoretical clinical strategy for restoration of vision, if the mechanism of re-establishment of maps and reconnection to appropriate targets during regeneration can be determined. This is the process of axon guidance, and underlines the importance of our research into the molecular determinants that guide normal development of the visual system.
Topics: Animals; Astrocytes; Axons; Central Nervous System; Humans; Nerve Regeneration; Oligodendroglia; Optic Nerve; Optic Nerve Injuries; Peripheral Nerves
PubMed: 9713068
DOI: 10.1136/bjo.82.5.577 -
NeuroImage Aug 2019In vivo human optic nerve diffusion magnetic resonance imaging (dMRI) is technically challenging with two outstanding issues not yet well addressed: (i) non-linear optic...
In vivo human optic nerve diffusion magnetic resonance imaging (dMRI) is technically challenging with two outstanding issues not yet well addressed: (i) non-linear optic nerve movement, independent of head motion, and (ii) effect from partial-volumed cerebrospinal fluid or interstitial fluid such as in edema. In this work, we developed a non-linear optic nerve registration algorithm for improved volume alignment in axial high resolution optic nerve dMRI. During eyes-closed dMRI data acquisition, optic nerve dMRI measurements by diffusion tensor imaging (DTI) with and without free water elimination (FWE), and by diffusion basis spectrum imaging (DBSI), as well as optic nerve motion, were characterized in healthy adults at various locations along the posterior-to-anterior dimension. Optic nerve DTI results showed consistent trends in microstructural parametric measurements along the posterior-to-anterior direction of the entire intraorbital optic nerve, while the anterior portion of the intraorbital optic nerve exhibited the largest spatial displacement. Multi-compartmental dMRI modeling, such as DTI with FWE or DBSI, was less subject to spatially dependent biases in diffusivity and anisotropy measurements in the optic nerve which corresponded to similar spatial distributions of the estimated fraction of isotropic diffusion components. DBSI results derived from our clinically feasible (∼10 min) optic nerve dMRI protocol in this study are consistent with those from small animal studies, which provides the basis for evaluating the utility of multi-compartmental dMRI modeling in characterizing coexisting pathophysiology in human optic neuropathies.
Topics: Adult; Algorithms; Diffusion Tensor Imaging; Female; Humans; Image Processing, Computer-Assisted; Male; Optic Nerve; Signal Processing, Computer-Assisted; Signal-To-Noise Ratio; Young Adult
PubMed: 30930313
DOI: 10.1016/j.neuroimage.2019.03.058 -
Indian Journal of Ophthalmology Apr 2014Many systemic antimicrobials have been implicated to cause ocular adverse effects. This is especially relevant in multidrug therapy where more than one drug can cause a...
Many systemic antimicrobials have been implicated to cause ocular adverse effects. This is especially relevant in multidrug therapy where more than one drug can cause a similar ocular adverse effect. We describe a case of progressive loss of vision associated with linezolid therapy. A 45-year-old male patient who was on treatment with multiple second-line anti-tuberculous drugs including linezolid and ethambutol for extensively drug-resistant tuberculosis (XDR-TB) presented to us with painless progressive loss of vision in both eyes. Color vision was defective and fundus examination revealed optic disc edema in both eyes. Ethambutol-induced toxic optic neuropathy was suspected and tablet ethambutol was withdrawn. Deterioration of vision occurred despite withdrawal of ethambutol. Discontinuation of linezolid resulted in marked improvement of vision. Our report emphasizes the need for monitoring of visual function in patients on long-term linezolid treatment.
Topics: Acetamides; Anti-Infective Agents; Diagnosis, Differential; Humans; Linezolid; Male; Middle Aged; Optic Nerve; Optic Nerve Diseases; Oxazolidinones; RNA, Ribosomal, 23S; Tomography, Optical Coherence; Visual Acuity
PubMed: 24088636
DOI: 10.4103/0301-4738.118451 -
Zhurnal Voprosy Neirokhirurgii Imeni N.... 2014Neoplasms extending to the optic canal is a diverse group of more than 15 histological types. Elimination of the optic nerve compression is crucial for favorable visual... (Clinical Trial)
Clinical Trial
Neoplasms extending to the optic canal is a diverse group of more than 15 histological types. Elimination of the optic nerve compression is crucial for favorable visual outcome. Material and method. We perform a prospective analysis of 97 patients with different neoplasms with involvement of the optic canal in whom surgery was performed in neurooncological department of Burdenko Neurosurgical Institute during the period from 2010 to 2012. Extent of resection and recurrence rates were determined by pre- and postoperative CT and MRI studies. Results. 97 patients (78 women and 19 men) were involved in the study. Mean age was 49,4 years. Patients were followed for mean of 15.9 months (1-36 month). Total resection was achieved in 54 (55.6%) patients, gross-total resection in 40 (41,2%), partial resection in 3 (3.2%). Underwent postoperative stereotactic radiation therapy 30 patients. There was no recurrence in a series of observations. 4 patients showed extension into both optic canals. Visual disturbances were the main presenting symptoms in 50 (51.5%) patients. 10 (10.3%) patients had normal visual status initially. Visual improvement after surgery was seen in (37%) of 87 patients with visual disturbances. Visual deterioration occurred in 17 (19%) patients. Transient visual deterioration occurred in 1 patient with recovery to the base level over time. The visual outcome was affected by the duration of the symptoms before surgery and the stage of visual disturbances according to the eyeground changes. Conclusions. Involvement of the optic canal is a common phenomenon in craniofacial tumors. Neoplasms extending to the optic canal is a diverse group of both the localization and histology. Decompression of the optic nerves is a crucial step in the surgical management of this neoplasms to optimize visual recovery and prevent tumor recurrence.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Brain Neoplasms; Child; Decompression, Surgical; Female; Humans; Male; Middle Aged; Optic Nerve
PubMed: 25406807
DOI: No ID Found