How to draw Medulla Oblongata Cross-section ?

Like in Midbrain and Pons:

  1. Corticospinal tract passes ventrally
  2. Ventricular system is located dorsally in midline
  3. Cranial nerve nuclei are located just anterior to the ventricle
  4. Medial longitudinal fasciculus is present around the center

Another important thing to remember is that, the caudal medulla resembles “spinal cord“:

  1. Circular in shape
  2. Have central canal instead of 4th ventricle
  3. Have nucleus gracilis and nucleus cuneatus dorsally
  4. Site where pyramids and medial lemnisci decussate

medulla drawing

How to draw medulla cross-section ?

  1. Draw a pair of circles
    • Represents inferior cerebellar peduncle
  2. Draw another pair of circles anteriorly
    • Represents inferior olivary nucleus
  3. Draw a triangle in the center between 2 posterior circles
    • Represents 4th ventricle
  4. Draw a pair of triangles anterior to the 2 anterior circles
    • Represents pyramids
  5. Draw a boomerang just anterior to the triangle representing 4th ventricle
    • Represents periventricular gray
  6. Draw another boomerang anterior to the previous boomerang
    • Represents cranial nerve nucleii (from medial to lateral)
      • CN XII
      • Dorsal vagal nucleus
      • Nucleus tractus solitarius
      • Medial vestibular nucleus
      • Posterior cochlear nucleus
  7. Draw a pair of rectangles in the center
    • Represents medial lemniscus (anteriorly) and Medial Longitudinal Fasciculus (MLF) posteriorly
  8. Draw a pentagon with apex tilted medially, just anterior to the posterior pair of circles – the 5 points of the pentagon represents 5 structures (starting from apex in clockwise fashion)
    • Nucleus ambiguus
    • Trigeminal nerve nucleus and spinal tract
    • Anterior cochlear nucleus
    • Anterior spinocerebellar tract
    • Lateral spinocerebellar tract
    • Lateral spinothalamic tract inside the pentagon

Now, look how a real cross-section would look like:

medulla cross section
From teachmeanatomy.info

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