Objective: The present work was aimed at studying the ultra structural changes of the proximal (retinal) stump of the intracranially transected optic nerve of the rat for any possible regenerative ability.
Methods: Specimens were collected one (1 wpo) and four weeks(4 wpo) after the transection and the cross sections of the stumps were studied by electron microscopy by dividing them into three zones, (1) the central zone, (2) the intermediate zone, and (3) the peripheral zone.
Results: The present results showed evident morphological changes in these zones both in the 1 wpo and 4 wpo groups. The signs of degeneration were more marked in the central zone than in the peripheral zone and they were more prominent in the 1 wpo group than in the 4 wpo group. The most prominent sign of the degeneration was loss or lack of the healthy myelinated axons. The main evidence of the regenerative ability was the reappearance of the apparently healthy myelinated axonal profiles, with a parallel decrease of the non myelinated ones. This regenerative feature was more prominent peripherally and might be an indication that ischemia was the cause of optic nerve degeneration.
Conclusions: The present work revealed a clear morphological evidence of the regenerative capability of the intracranially transected optic nerve though it is considered as a part of the CNS.
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Surg Radiol Anat
January 2025
Department of Ophthalmology & Visual Sciences, University of Adelaide, North Terrace, Adelaide, SA, 5000, Australia.
Purpose: To report the normative dimensions of the frontal nerve (FN) on fat-suppressed suppressed gadolinium (fs-gad) enhanced magnetic resonance imaging (MRI).
Method: A retrospective cohort study of patients who underwent coronal fs-gad T1-weighted MRI. Orbits were excluded if there was unilateral or bilateral pathology of the FN or optic nerve sheath (ONS), incomplete MRI sequences, poor image quality or indiscernible FN on radiological assessment.
J Glaucoma
January 2025
Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI.
Precis: Current optical coherence tomography normative sample data may not represent diverse human optic nerve anatomy to accurately classify all individuals with true glaucomatous optic neuropathy.
Purpose: To compare optic nerve head (ONH) measurements between published values from an optical coherence tomography (OCT) normative database and a more diverse cohort of healthy individuals.
Patients And Methods: ONH parameters from healthy participants of the Michigan Screening and Intervention for Glaucoma and Eye Health through Telemedicine (MI-SIGHT) program and the Topcon Maestro-1 normative cohort were compared.
The visual system of teleost fish grows continuously, which is a useful model for studying regeneration of the central nervous system. Glial cells are key for this process, but their contribution is still not well defined. We followed oligodendrocytes in the visual system of adult zebrafish during regeneration of the optic nerve at 6, 24, and 72 hours post-lesion and at 7 and 14 days post-lesion via the sox10:tagRFP transgenic line and confocal microscopy.
View Article and Find Full Text PDFJ Neuroinflammation
January 2025
Department of Neurology, Division of Neuroimmunology, School of Medicine, Johns Hopkins University, Baltimore, MD, 21287, USA.
Chronic innate immune activation in the central nervous system (CNS) significantly contributes to neurodegeneration in progressive multiple sclerosis (MS). Using multiple experimental autoimmune encephalomyelitis (EAE) models, we discovered that NLRX1 protects neurons in the anterior visual pathway from inflammatory neurodegeneration. We quantified retinal ganglion cell (RGC) density and optic nerve axonal degeneration, gliosis, and T-cell infiltration in Nlrx1 and wild-type (WT) EAE mice and found increased RGC loss and axonal injury in Nlrx1 mice compared to WT mice in both active immunization EAE and spontaneous opticospinal encephalomyelitis (OSE) models.
View Article and Find Full Text PDFJ Glaucoma
January 2025
Department of Ophthalmology, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria Hospital Clínico San Carlos (IdISSC), Universidad Complutense. Madrid, Spain.
Prcis: The discriminant function of glaucoma, obtained by the Laguna ONhE colorimetric program, significantly correlates with the BMO-MRW. Furthermore, the diagnostic capacity was inferior to other structural tests in POAG patients.
Purpose: To evaluate the diagnostic capability for glaucoma and the correlation between peripapillary and macular parameters using spectral domain optical coherence tomography (SD-OCT) and optic nerve head hemoglobin (OHN Hb) levels assessed by the Laguna ONhE® software using colorimetric analysis.
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