The American encyclopedia and dictionary of ophthalmology Edited by Casey AWood, assisted by a large staff of collaborators . veins. In additionto these, fine branches run toward the macular region, and alsotoward the nasal side. The whitish or light pink appearance of the papilla, as seen withthe ophthalmoscope, is due to the fact that the lamina cribrosa andthe medullated fibres beyond it, are seen through the translucentaxis-cylinders that make up the substance of the papilla itself. Out-lining the disc is the edge of the sclera; when seen with the ophthal-moscope it appears as the white sc
The American encyclopedia and dictionary of ophthalmology Edited by Casey AWood, assisted by a large staff of collaborators . veins. In additionto these, fine branches run toward the macular region, and alsotoward the nasal side. The whitish or light pink appearance of the papilla, as seen withthe ophthalmoscope, is due to the fact that the lamina cribrosa andthe medullated fibres beyond it, are seen through the translucentaxis-cylinders that make up the substance of the papilla itself. Out-lining the disc is the edge of the sclera; when seen with the ophthal-moscope it appears as the white scleral ring. In many cases, one mayalso distinguish at the margin of the papilla some of the underlying ANATOMY (GROSS) OF THE HUMAN EYE 399 choroidal pigment, which shows as a crescentic line, partially or com-pletely surrounding the disc. Within all of these is the light-pinkcolor of the nerve itself. Optic nerve fibres compose most of the papillary substance and donot perceive light; hence we find with the perimeter that the disccorresponds to a blind area or scotoma, called in this instance theblind spot of lOS LCD The Path of Light Imprcssious from the IJetina to the Occipital Lobe.(Visual Center.) In their course from the calcarine fissure in the brain the opticradiations send fibres to almost every large center—both cerebraland spinal—thus demonstrating anatomically what the ophthalmolo-gist has long known from clinical observation, viz.: that almostevery lesion of the brain or cord is sooner or later followed by morbidalterations in, or functional disturbances of, some portion of thevisual mechanism. To follow again and briefly the path of the optic fibres:—In theoccipital lobe they occupy a narrow area and rather shallow positionabout the edges of the calcarine fissure. Passing forward and down-ward toward the base of the brain from the calcarine fissure andcuneus, the optic fibres from each hemisphere dip beneath the angu-lar gyrus, receiving numerous
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectophthalmology, bookye
