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International Foundation for Optic Nerve Disease

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 ^ Sarcoidosis


 ^ Schwann Cell Supporting cell of the peripheral nervous system. Forms a myelin sheath around peripheral nerves. Thought to contribute significantly to the ability of peripheral nerves to regenerate after being damaged as opposed to the less regenerating nature of central nervous system nervous tracts including the optic nerve which use oligodendrocytes to make the myelin sheaths.

Bernstein, SL; Guo, Y; Kerr, C; Fawcett, RJ; Stern, JH; Temple, S; Mehrabian, Z. “The optic nerve lamina region is a neural progenitor cell niche.” Jul 28, 2020. Proceedings of the National Academy of Sciences of the United States of America.

Mari Dezawa, Emiko Adachi-Usami. Role of Schwann cells in retinal ganglion cell axon regeneration. Progress in Retinal and Eye Research Volume 19, Issue 2 March 2000 Pages 171-204 PMID 10674707

Ahmed Z, Suggate EL, Brown ER, Dent RG, Armstrong SJ, Barrett LB, Berry M, Logan A. Schwann cell-derived factor-induced modulation of the NgR/p75NTR/EGFR axis disinhibits axon growth through CNS myelin in vivo and in vitro. Brain. 2006 Jun;129(Pt 6):1517-33. Epub 2006 Apr 13. PMID 1661389

Wong EV, David S, Jacob MH, Jay DG. Inactivation of myelin-associated glycoprotein enhances optic nerve regeneration. J Neurosci. 2003 Apr 15;23(8):3112-7. PMID 12716917


Wikipedia Schwann cell

 ^ Sclera

Wikipedia Sclera

 ^ Scotoma A gap in the visual field as measured by visual field perimetry within otherwise normal vision. The site of the lesion of the visual pathway determines the shape and location of the scotoma. There are typical shapes of scotomas in optic nerve disease: 1. Centrocecal scotomas, which lie in the centre of vision to the blind spot (cecum), represent lesions of the nerves between the macula and papilla; 2. Arcuate or altitudinal scotomas , lying next to the horizontal midline of the field, represent lesions of the temporal retina above and below the maculopapillary bundle or of the superior or inferior temporal side of the optic nerve; and 3. Radial scotomas which are supero- or infero-temporal defects extending to the blind spot and represent lesions of the nasal retina or optic nerve. 4. Nasal steps are nasal peripheral defects along the nasal horizontal meridian. 5. Generalized depression though not strictly a scotoma is a lower sensitivity over the whole visual field which may be detected with visual field perimetry. Retinal lesions correspond to the visual field defect. For example, macular lesions cause centrocecal defects and retinal degenerative diseases like retinitis pigmentosa usually produce constricted fields and equatorial ring scotomas. Lesions at or beyond the optic chiasm result in scotomas with sharp naso-temporal edges. Scotoma depth is the measure of degree of loss comparing the surround to the area of loss.


 ^ Serine


 ^ Serotonin


 ^ Sildenafil see Viagra


 ^ Single cell recording


 ^ Sinus venosus sclerae see Canal of Schlemm

 ^ Slit lamp Optical examining tool for the front part of the eye. Typically uses a slit shaped light source and steadying harness for patient's head.


 ^ Soma Body of cell or of whole organism. e.g.Referring to the cell body as opposed to the axon in a neuron. Or, in genetics, referring to cells of the body (somatic) as opposed to germ line (reproductive) cells.


 ^ Stem cell Primordial cell of a tissue or class of cells. The optic nerve has stem cells in the narrow lamina. Much work is being done on understanding stem cells for their use as models of disease using induced pluripotential stem cells and their transplant potential in treating many diseases including nerve tissue diseases.

Bernstein, SL; Guo, Y; Kerr, C; Fawcett, RJ; Stern, JH; Temple, S; Mehrabian, Z. “The optic nerve lamina region is a neural progenitor cell niche.” Jul 28, 2020. Proceedings of the National Academy of Sciences of the United States of America.

Shi Y, Inoue H, Wu JC, Yamanaka S. Induced pluripotent stem cell technology: a decade of progress. Nat Rev Drug Discov. 2017 Feb;16(2):115-130. doi: 10.1038/nrd.2016.245. Epub 2016 Dec 16. PMID: 27980341; PMCID: PMC6416143.

Wikipedia stem cell

 ^ SPECT Single photon emission computed tomography


 ^ Subarachnoid space


 ^ Superior colliculus Midbrain structure involved in directing behaviour in body centred space, eye movement, and distractability.


 ^ Superoxide dismutase


 ^ Suprachiasmatic nucleus Small region of the brain in the hypothalamus, situated directly above the optic chiasm, responsible for controlling circadian rhythms. Receives input from melanopsin containing retinal ganglion cells via the retinohypothalamic tract.

Wikipedia Suprachiasmatic nucleus

Wikipedia Retinohypothalamic tract

 ^ Suramin sodium Anti HIV drug known to cause optic nerve damage. See also Zidovudine.


 ^ Synapse Junction between axon and dendrite where neurotransmitters are released and taken up.


 ^ Synuclein A family of homologous proteins of low molecular weight that are predominately expressed in the brain and that have been implicated in a variety of human diseases. Gamma synuclein is found in the eye. It may play a role in glaucoma and other optic nerve diseases.

ARVO Annual Meeting Abstract | April 2010 Gamma-Synuclein Aggregation and Activation of Optic Nerve Head Astrocytes. N. Marsh-Armstrong; I. Soto; E. Oglesby; C.-H. O. Davis; E. H. Mules; F. Valiente-Soriano; M. Vidal-Sanz; V. Buchman; P. A. Watkins; J. V. Nguyen

Nguyen JV, Soto I, Kim KY, Bushong EA, Oglesby E, Valiente-Soriano FJ, Yang Z, Davis CH, Bedont JL, Son JL, Wei JO, Buchman VL, Zack DJ, Vidal-Sanz M, Ellisman MH, Marsh-Armstrong N. Myelination transition zone astrocytes are constitutively phagocytic and have synuclein dependent reactivity in glaucoma. Proc Natl Acad Sci U S A. 2011 Jan 18;108(3):1176-81. doi: 10.1073/pnas.1013965108. Epub 2011 Jan 3. PMID: 21199938; PMCID: PMC3024691.

Wikipedia synuclein

Wikipedia gamma synuclein

Wikipedia synucleinopathy

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