Unit 2 Central Nervous System

  1. encephalon=
    medula spinalis=
    • brain
    • spinal cord
  2. cortex
    outer portion
    (shows lighter on CT)
    gray matter
  3. inner portion
    (shows darker on CT)
    white matter
  4. three major parts of the brain:
    • cerebrum
    • cerebellum
    • brain stem
  5. parts of the brain stem
    • diencephalon
    • midbrain (mesencephalon)
    • pons
    • medulla
  6. components of forebrain
    • cerebrum
    • diencephalon
  7. components of midbrain
    • stemlike portion that connects the cerebrum to the pons and cerebelum
    • connects forebrain to hindbrain
  8. components of hindbrain
    • cerebellum
    • pons
    • medulla oblongata
  9. largest part of the brain.
    longitudinal fissures (R&L hemispheres with ventricles)
  10. contains hypothalamus and thalamus.
    composed of structures located near midline of the brain
    contains pituitary gland (inferiorly) (aka hypophysis cerebri)
  11. largest part of hindbrain.
    transverse sulci gives it a sauliflower look.
  12. tissue b/w sulci or fissures of cerebellum
  13. median constricted area the serperates the hemispheres of the cerebellum
  14. seperates the cerebellum from cerebrum
    transverse cleft
  15. the                       of the cerebrum divides it into right and left hemispheres
    longitudinal fissure
  16. connects the cerebral hemisphere.
    main nerve fiber of cerebrum.
    corpus callosum
  17. each cerebrum hemisphere has a                    that contain CSF and surrounds the 3rd ventricle
    lateral ventricle
  18. cerebral lobes:
    • frontal
    • parietal
    • temporal
    • occipital
    • insula
  19. slender, elongated structure.
    inner part is a gray cellular substance. (shaped like "H" when cut transversely)
    white fibrous substance surrounds the "H"
    spinal cord
  20. spinal cord connects to medulla oblongata at the level of
    • foramen magnum
    • "great whole"
  21. spinal cord extends to the space of the
    1st or 2nd lumbar vertebrae
  22. the pointed area where the cord ends
    conus medullaris
  23. fibrous strand that extends from the conus medullaris and attaches the cord to the upper coccygeal segment
    filum terminale
  24.              pairs of spinal nerves are transmitted thru the intervertebral and sacral foramina
  25. nerves below the termination of the spinal cord that extend inferiorly thru the vertebral canal
    (resembles a horses tail)
    cauda equina
  26. lower portion of the dura that extends below the spinal cord to the level of S2 that encloses the cauda equina
    dural sac
  27. protective membranes that cover brain and spinal cord
  28. inner sheath "tender mother"
    highly vascular
    adheres closely to the underlying brain and cord structure
  29. delicate central sheath
    resembles a spider web
  30. hard "tough mother"
    fibrous outermost protective sheath of the spinal cord
    adheres to bone
  31. two layers of dura:
    • endosteal
    • meningeal
  32. outer layer of dura
    lines the cranial bones serving as periosteum
  33. inner layer of dura
    spaces for venous sinuses which are large venous blood vessels
  34. b/w the dura and the vertebral periosteum
  35. b/w dura and arachnoid
  36. b/w arachnoid and pia
    filled with CSF
    communicates with ventricles
    contains cisternae
  37. contained in the ventricles of the brain and the subarachnoid space.
    water cushion protecting the brain and spinal cord from physical injury.
    coats the spinal cord in nutrients.
    cerebrospinal fluid
  38. CSF can increase and decrease with shrinking or expanding of                       
    cranial contents
  39. secretes CSF
    network of capillaries located in the ventricles
    choroid plexus
  40. widened areas of the subarachnoid space.
    filled with CSF
  41. widest space of the subarachnoid space.
    triangular in shape and at the post-sup part of the subarachnoid space b/w the base od the cerebellum and dorsal surface of the medulla oblongata
    • certerna magna
    • cisternae cerebellomedularis
  42.                      allow communication fo the subarachnoid space and ventricles
  43. median aperature:
    foramen of magendie
  44. lateral aperature:
    foramen of lusckka
  45. bleeding b/w dura and skull
    involves artery
    epidural hematoma
  46. bleeding b/w dura and arachnoid
    involves vein
    subdural hematoma
  47. four partitions of the dura
    • falx cerebri
    • R & L tentorium
    • falx cerebelli
  48. runs through the interhemispheric fissure and provides support for the cerebral hemispherers
    falx cerebri
  49. seperates the occipital lobe of the cerebrum from the cerebellum
  50. seperates the two cerebelli hemispheres
    falx cerebelli
  51. name the portions of the ventricles:
    • body- central portion
    • anterior- frontal horn
    • posterior- occipital horn
    • inferior- temporal horn
  52. the 3rd ventricle is                in shape while the 4th ventricle is                  in shape
    • quadrilateral
    • diamond
  53. the pointed end of the 4th ventricle is continuous with the                                                 
    central canal of the medulla oblongata
  54. connects each lateral ventricle to the 3rd ventricle
    • interventricular foramen
    • "foramen of monroe"
  55. the 3rd ventricle also communicates with the 4th ventricle through the
    cerebral aqueduct of "acqueduct of sylvius"
  56. CSF flow:
    • lateral ventricles
    • interventricular foramen
    • 3rd ventricle
    • acqueduct of sylvius
    • 4th ventricle
    • median and lateral aperatures (magendie and lyscka)
    • cisternae magna
    • remainder of aubarachnoid space
  57. radiographic examination of the CNS structures within the vertebral canal such as spinal chord and nerve root branches
  58. in myelography an intrathecal injection is made and                    contrast is put into the                    space and the spinal chord and nerve roots are outlined
    • non ionic water soluble inert (non reactive)
    • subarachnoid
  59. what are the two areas that can be punctured for myelography
    • L2-L3 or L3-L4 interspace
    • cisterna cerebellomedullaris
  60. name 3 non ionic agents used in myelography
    • iohexol (omnipaque)
    • iopamidol (isovue)
    • ioversol (optiray)
  61. how much contrast is used for c-spine myelography?
    T spine?
    L spine?
    • C&L 9-12 cc's water soluble
    • T 25-30 cc oil and 12 cc water soluble
  62. contraindications to myelogram
    • blood in the CSF
    • arachnoiditis
    • increased intracranial pressure
    • previous lumbar puncture performed within 2 weeks of current
  63. steps to myelogram
    • explain the details of the exam to the pt
    • consent form
    • 1 hour before exam, sedative is given
    • pt should be well hydrated
    • use aseptic technique
  64. the head must be extended while the patient in the trendelenburg position to
    prevent contrast from flowing into the ventricles
  65. steps to cervical puncture myelography
    • pt seated prone with head flexed to place the external occipital protuberence in line with the spinous processes
    • shave area
    • clean skin with antiseptic
    • local anesthetic
    • when needle is inplace position table to prevent contrast from entering the ventricles
    • remove needle and extend neck
  66. centering for a cervical myelography
    • vertical or horizontal ray may be used
    • center to C5
  67. routine images for lumbar myelography
    • AP or PA
    • x table with grid
    • obliques
    • conus projections for conus medullaris:
    • AP centered to T12 L1

    images followed by CT
  68. explain post myelogram patient care
    • pt's head and shoulders elevated 30-45 degrees
    • remain in recovery for 4-8 hours and rest for several hours
    • plenty of fluids
    • exam of the puncture site before departure
  69. CT myelography is done to:
    • done to visualize size, shape, and position of the spinal cord and nerve roots
    • 1.5-3mm slices
  70. radiologic examination of individual intervertebral disks
  71. routine for a CT head
    • gantry angle 20-25 degrees to OML
    • lowest slice, upper cervical/foramen magnum and the roof of the orbits are seen.
Card Set
Unit 2 Central Nervous System
Unit 2 CNS