Qtr 3 Head and neck neurology Exam 1 Vision

Card Set Information

Qtr 3 Head and neck neurology Exam 1 Vision
2013-04-14 21:04:47

Show Answers:

  1. What retinal layer are the rods and cones found in?
    Outer nuclear layer
  2. What retinal layer are the horizontal cells, bipolar cells, and amacrine cells found?
    Inner nuclear layer
  3. What layer of the retina are the ganglia found?
    inner plexiform layer
  4. What are the three symptoms of vitamin A deficency in the eye?
    • Nycatopia (night blindness)
    • Xerosis (Drying of eye, Cornea)
    • Xerophthalmia (faliure to produce tears)
  5. What is the medical term for night blindness?
  6. what is the medical term for drying of the eye or cornea?
  7. What is the medical term for the failure to produce tears?
  8. What is the main blood supply of the retina?
    Central retinal artery
  9. What is the main purpose of vitamin A in vision?
    Converts 11-trans retinal back to 11-cis retinal
  10. What is protanope ?
    Loss of red cones
  11. What is deuteranope?
    loss of green cones
  12. What are the most common types of color blindness?
    Protanope (loss of red cones)

    Deuteranope (Loss of green cones)
  13. What causes the Na+ channels to close during visual stimulation?
    Decrese in cGMP as it is converted to 5GMP by phosphodiesterase?
  14. During phototropic conditions what are most photochemicals reduced to?
    Retinal and opsins
  15. During scotopic conditions what does retinal convert back to?
  16. What is the visual pathway?
    • 1. optic nerve
    • 2. optic chiasm 
    • 3. optic tract
    • 4. dorsal lateral geniculate body
    • 5. optic radiation
    • 6. Visual cortex
  17. What are the four parts of the old visual system?
    • 1.Suprochiasmatic nucleus of hypothalamus
    • 2. Pretectal nuclei 
    • 3. Superior Colliculus
    • 4. Ventral lateral genicuate body
  18. What is the main function of the suprachiasmatic nucleus of the hypothalamus?
    Regulate circadian rhythms
  19. What is the function of the pretectal nuclie?
    • Pupillary light reflex
    • Accommodation of lens
  20. How many layers are in the dorsal lateral geniculate body?
    6 layers
  21. What is the function of layers II, III, and V of the LGB?
    Receive info from lateral half of ipsilateral eye
  22. What is the function of layers I, IV, VI of the LGB?
    Receive info from medial half of contralateral eye
  23. What are the magnocellular layers of the LGB?
    Layers I, II
  24. What are the main features of the magnocellular layers (I, II) of the LGB?
    • Rapid conduction to V1
    • Comprised of large Y ganglion cells
    • Black and white only
    • Poor, point-to-point
  25. What LGB layers contain small to medium X retinal cells, have a moderate conduction, and Good color /  point-to-point.
  26. In what layer of the visual cortex do geniculocalcarine signals enter first?
  27. What is a blind spot in the field of vision called?
  28. What is Retinitis pigmentosa?
    Melanin deposits of retina
  29. What is strabismic Amblyopia?
    Lazy Eye
  30. What disease has lens accommodation, no pupil reaction, associated with neurosyphilis?
  31. What are the three parts of the uveal tract?
    • Ciliary body
    • Choroid 
    • Iris
  32. What eye muscle is responsible for miosis?
    Sphincter pupalae m.
  33. What nerve is responsible for miosis and what type of innervation does it have?
    CN 3 (Parasympathetic)
  34. What tract in the eye has the following order Retina-->optic nerve--> pretectal neurons--> edinger-westphal neuron--> Ciliary ganglia-->sphincter pupalae muscles (Via Acetylcholine)?
    Light Reflex
  35. What function of the eye is the following derived? Superior thoracic spinal chord--> preganglionic neurons--> superior cervical ganglion--> Dilator pupalae muscles?
    Mydriasis (sympathetic)
  36. what reflex utilizes increased optic power, pupillary constriction, activation of medial rectus muscles ?
    Accommodation Reflex
  37. How much of the refractory power is derived from the cornea?
  38. What is the total refractory power of the eye?
  39. what cranial nerve controlls accommodation? and is it sympathetic or parasympathetic?
    Oculomotor CNIII
  40. What ligament and muscle are used to adjust the length of the lens?
    • Suspensory ligament
    • Ciliary musccle
  41. What is the inability to accommodate which may be caused by denaturing of proteins of the lens?
  42. What is the normal papillary diameter?
    1.5 to 8mm
  43. What type of correction is needed for astigmatism?
    Spherical lens
  44. What is caused by short eye or weak lens which causes the focal point to be behind the retina?
    Hyperopia (far sighted)
  45. What type of lens is used to correct hyperopia?
  46. What is myopia and what type of lens is used to fix it?
    • Near sighted 
    • focal point anterior to retina

    Concave lens
  47. What is caused by O2 toxicity in premature babies?
    Retrolental fibroplasia
  48. What is the normal ocular pressure?
    12-20 mm hg
  49. What is a malignant retinal tumor in children?
  50. What retinopathy is seen as microaneurysm, exudate, and hemorrage?
  51. What retinopathy is seen as flame hemorrhage, papilloedema, cotton wool spots, and hard exudate?