. Anatomy, descriptive and applied. Anatomy. THE RETINA, OB TUNICA INTERNA 1101 an eminence, the optic papilla (colliculiis nervi optici); the central portion is depressed and is called the optic cup (excavatio papillae nervi optici). The arteria centralis retinae pierces its centre. This is the only part of the surface of the retina from which the power of vision is absent, and is termed the blind spot. CHOROID POSTERIOR HORT CILIARY ARTERY AND~ VEIN. Fig. 819.—The terminal portion of the optic nerve and its entrance into the eyeball, : (Toldt.) , Structure.—The retina is an exceedingly compl
. Anatomy, descriptive and applied. Anatomy. THE RETINA, OB TUNICA INTERNA 1101 an eminence, the optic papilla (colliculiis nervi optici); the central portion is depressed and is called the optic cup (excavatio papillae nervi optici). The arteria centralis retinae pierces its centre. This is the only part of the surface of the retina from which the power of vision is absent, and is termed the blind spot. CHOROID POSTERIOR HORT CILIARY ARTERY AND~ VEIN. Fig. 819.—The terminal portion of the optic nerve and its entrance into the eyeball, : (Toldt.) , Structure.—The retina is an exceedingly complex structure, and, when examined micro- scopically by means of sections made perpendicularly to its surface, is found to consist of many layers of nerve elements bound together and supported by the sustentacula! fibres. The layers of the retina are: 1. Membrana limitans interna. 2. Layer of nerve fibres (stratum opticum). 3. Ganglionic layer, consisting of nerve cells. 4. Inner plexiform layer. 5. Inner nuclear layer, or outer ganglionic layer. 6. Outer plexiform layer. 7. Outer nuclear layer, or layer of outer granules. 8. Membrana limitans externa. 9. Jacob's membrane (layer of rods and cones). 10. Pigmentary layer (tapetiun nigrimi). 1. The membrana limitans interna is the most internal layer of the retina and is in contact ?with the hyaloid membrane of the vitreous humor. It is derived from the supporting frame- work of the retina, with which tissue it will be described. 2. The layer of the nerve fibres consists of the axones proceeding from the nerve cells in the inner ganglionic layer. They are amyelinic, and, concentrating at the porus opticus, pass through all the layers of the retina except the membrana hmitans interna. On passing through the lamina cribrosa of the sclera these axones acquire myelin sheaths and leave the eyeball as a com- pact rounded bundle called the optic nerve A few of the fibres in tliis layer are centrifugal, being axones of ganglion cells wi
Size: 1989px × 1257px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, booksubjectanatomy, bookyear1913
