retina NBEO.txt

Card Set Information

retina NBEO.txt
2015-02-24 15:21:00
Retina NBEO Optometry

Retina NBEO Optometry
Show Answers:

  1. What are the layers of the retina from most exterior to the most interior?
    • RPE
    • Photoreceptor layer
    • External limiting membrane
    • Outer nuclear layer
    • Outer plexiform layer
    • Inner nuclear layer
    • Inner plexiform layer
    • Ganglion cell layer
    • Nerve fiber layer
    • Internal limiting membrane
  2. What is the retina derived from?
    Neuronal ectoderm
  3. What is the order of synapse in the Retinal layers?
    • Converted to neuronal signal by photoreceptors
    • Received by bipolar cells
    • Synapse with ganglion cell
    • Transmitted to brain
  4. Where are the horizontal cells located?
    Inner nuclear layer
  5. What layer of the retina connects to bruch's membrane?
  6. What layer in the retina is responsible for phagocytosis of photoreceptor outer segments?
  7. What layer acts as a transport of ions between the choroid and the retina?
  8. What do the outer segments of the photoreceptors do?
    Make discs
  9. What do the inner segments of the photoreceptor cells do?
    • Make photopigments
    • Protein synthesis
  10. What is the nm for Rhodopsin?
    507 nm
  11. Where are the rods most dense in the retina?
    5mm from fovea
  12. What photopigment is found in rods?
  13. What photopigments are found in cones?
    • Erythrolabe (red) 588nm, long
    • Chlorolabe (green) 531nm, medium
    • Cyanolabe (blue) 420nm, short
  14. What does the external limiting membrane do?
    Contains attachments between muller cells and inner segments of photoreceptors
  15. What is in the outer nuclear layer?
    The cell bodies of rods and cones
  16. What is in the outer plexiform layer?
    Rod spherules and cone pedicles
  17. What is the only retinal layer to receive blood supply from both the choroid and the retina?
    Outer plexiform layer
  18. What is Henle's fiber layer?
    Name given for outer plexiform layer in the macula
  19. Where is the first synapse in the visual pathway?
    Outer plexiform layer
  20. Where is the site of retinoschisis?
    Outer plexiform layer
  21. Where is the site of hard exudates?
    Outer plexiform layer
  22. What do the horizontal cells do?
    • Lateral inhibition
    • Contribute to special summation
  23. Where is the second synapse in the visual pathway located?
    Inner plexiform layer
  24. What cells are involved in the 2nd synapse of the visual pathway?
    Ganglion dendrites and bipolar axons
  25. What do bipolar cells do?
    Relay information between photoreceptor cells (dendrite) and horizontal (dendrite), amacrine (axon), and ganglion cells (axon)
  26. What neurotransmitters are there in the retina?
    • Glutamate
    • GABA
    • Glycine
  27. What does Glutamate do?
    Excites photoreceptor, bipolar, and most ganglion cells
  28. What do GABA and Glycine do?
  29. Where are GABA and Glycine released from?
    • Horizontal cells
    • Amacrine cells
  30. What do horizontal cells do?
    • inhibit
    • synapse with photoreceptors, bipolar cells, horizontal cells
  31. what is the ratio for bipolar cells to cones?
  32. With what cell do rods synapse with?
    Amacrine cells
  33. What types of ganglion cells are there?
    • P1, midget ganglion
    • P2,
    • M, magnocellular
  34. What do midget ganglion cells connect to?
    Parvocellular layer of LGN
  35. What are midget ganglion cells responsible for?
    • Color vision
    • Parvocellular layer of LGN
  36. What are magnocellular responsible for?
    Discern movements and flickering light
  37. Where does CRAO cause necrosis?
    Ganglion cell layer
  38. Where do horizontal cells terminate?
    Outer plexiform layer
  39. What do amacrine cells do?
    • Inhibit ganglion cells
    • Center/surround for ROD cells
  40. What cells form the optic nerve?
    Axons of ganglion cells
  41. Where is the NFL thickest?
    At ONH
  42. Where is the NFL not present?
    In the macula
  43. Where are CWS found?
    Nerve fiber layer
  44. Where are splinter / drance hemes found?
    Nerve fiber layer
  45. Where are epiretinal membranes found?
    Internal limiting membrane
  46. What are muller cells?
    • Neuroglial cells that act as a buffer by regulating [K+ ions]
    • Maintain extracellular pH
    • Recycle GABA and Glutamate
    • Metabolize, synthesize and store glycogen
  47. What are microglial cells?
    Neuroglial cells that act as wandering phagocytes
  48. What are astrocytes?
    Neuroglial cells that provide structure to nerve fibers
  49. What layer secretes VEGF?
  50. What layer metabolizes and stores Vitamin A(retinol)?
  51. What layer is affected by RP, Stargardt's, and Best's disease?
  52. What neurotransmitter is typically found in dark conditions?
  53. Off bipolar cells depolarize in what conditions?
    Dark, hyperpolarizes in the light
  54. What part of the fovea contains the largest accumulation of bipolar and ganglion cells?
  55. What are the normal aging changes in the retina?
    • NFL decreases
    • Rod/cone density decrease
    • Atrophy (PPA)
    • Mullers cells become hypertrophic
    • Retinal vessels attenuate
  56. What does the A-wave represent in ERG?
  57. What does the B-Wave represent in ERG?
    Bipolar and muller cells
  58. What does the C-Wave represent in ERG?
  59. What does the D-Wave represent in ERG?
    Off-bipolar cell signal
  60. What is the ERG used to detect?
  61. What is the EOG used to detect?
    • Stargardt's
    • Advanced drusen
    • Best's disease
  62. What layers are drusens found?
    Between RPE and Bruch's
  63. What is the foveola?
    • Highest [cone] best VA
    • No bipolar / ganglion cells
    • No NFL
    • Foveal avascular zone
  64. What is the thickest area of the retina?