S4 Dissection Summary

S4 Dissection Summary


Part 1 - Removal of Calvaria

  • Section the scalp mid-sagittally
  • Reflect the soft tissue laterally to fully expose the skull
  • With an autopsy (Stryker) saw, complete a circumferential cut around the exposed bone of the calvaria
      • Preserve the meninges and brain


Part 2 - Meninges

  • Identify the dura mater covering the brain
  • Locate the superior sagittal sinus between the cerebral hemispheres
  • On one side, reflect the dura mater toward the midline to locate the superior cerebral vv.
  • Identify arachnoid mater and pia mater


Part 3 - Gross Brain

  • Sever the cranial nerves and vasculature where they enter the basicranium
  • Remove the brain
  • Identify the parts of the brain:
        • cerebrum
        • cerebellum
        • hypophysis (pituitary gland)
        • midbrain (on plastinated hemisected brain)
        • pons
        • medulla oblongata
  • Distinguish between the lobes of the cerebrum, and locate the longitudinal fissure
  • On a model or hemisected, plastinated brain, identify the components of the ventricular system
  • Focus on the inferior portion of the brain and brainstem
      • Locate the arteries on the inferior portions of the brain and anterior surface of the brainstem
      • Locate the cranial nerves (or components of the cranial nerves) from their origins on the brain and brainstem
  • Locate the dural partitions
    • Locate the dural venous sinuses within the dural partitions


Part 4 - Crainial Nerves (Cranial Base)

    • Locate the cranial nerves in association with the cranial base