1. Medulla Oblongata (bulbus/medulla)
Prof. Dr. Selda Önderoğlu

2. Medulla Oblongata The most inferior part of brain stem. It is like the
widening of spinal cord upwards.

3. surfaces of Medulla oblongata
Anterior
posterior

4. structures on the anterior surface (from midline laterally)
-Ant. Median fissure
-Pyramid
-pyramidal Decussation
-Anterolateral Sulcus
exits:Hypoglossal N.
-Olive
-Retroolivary Sulcus
Exits:
Glossophryngeal N.
vagus N.
accessory N.

5. Posterolateral surface of Medulla oblongata
glossopharyngeal N.
Vagus N.
Accessory N.
inferior cerebellar Peduncle

6. Inferior Cerebellar Peduncle connects medulla to cerebellum
Contains fibers of:
post. Spinocerebellar Tract
Some fibers of ant. Spinocerebellar tr.
cuneocerebellar tr.
Olivocerebellari tr.
vestibulocerebellar tr.
fibers from cerebellum to vestibular&reticular nuclei

7. Posterior surface of Medulla Oblangata is the lower triangle of rhomboid fossa

8. Rhomboid Fossa Is the space bw. Medulla+pons&cerebellum.
Filled with cerebrospinal fluid
Lower triangle is related to: medulla oblongata
Upper triangle to: pons

9. inferior part of post. Surface of Medulla Oblongata-from midline laterally has
posterior median
Sulcus
Fasciculus gracilis
Tuberculum gracilis(medial)
Tuberculum cuneatus (lateral)
Fasciculus cuneatus

10. Superior part of post. Surface of Medulla oblangata ( Rhomboid fossa’s lower triangle)
From midline laterally has:
post. median sulcus
Medial Eminence
Sulcus limitans
vestibular Area
Stria medullaris

11. Vestibular Nuclei 4 vestibular nuclei 1- superior 2- inferior 3-medial
4-lateral
Medial&inferior are at bulbus level

12. Cranial nerves emerging from medulla oblongata
Last 4 cranial nn.
glossopharyngeal n. (9)
Vagus n. (10)
Accessory n. (11)
Hypoglossal n. (12)

13. Cranial nerve Nuclei in brainstem

14. Nuc. ambiguus It is the The motor nucleus of glossopharyngeal n.
Vagus n.
Cranial part of accessory nerve
the nuclei of those 3 nn. Unite and form the nucl. Ambiguus

15. Spinal tract and nucleus of Trigeminal nerve
Related to pain and temperature sensation carried from head and neck regions.
Located at pons, medulla and upper 1-2 segments of spinal cord.
At medulla level it is located posterolaterally
Nuc. spinalis nervi trigemini bu tractus’un medialinde bulunur.

16. Solitary Tract Nucleus

17. Dorsal Nucleus of Vagus Nerve

18. Inferior Salivatory Nucleus

19. Brain stem (Cranial nerves)
Bulbus

20. Reticular Nuclei at medulla level
Nuc. reticularis lateralis
Nuc. reticularis ventralis
Nuc. reticularis gigantocellularis
Nuc. reticularis parvocellullaris
Nuc. reticularis paramedianus
Nuclei raphes
Nn. raphes obscurus
N. raphes pallidus
N. raphes magnus

21. Internal structure of Medulla Oblongata (transverse section at lower levels)
Pyramidal Decussation
Fasciculus gracilis
Fasciculus cuneatus

22. Transverse section at the level of pyramidal decussation
Nuc. cuneatus
Nuc. Gracilis
Spinal tract& nucleus of trigeminal nerve

23. Transverse section through the inferior level of olive
Cuneate nucleus
Accessorius cuneate nucleus
Nucleus gracilis
Spinal tract& nucleus of trigeminal nerve
lateral reticular Nucleus

24. Transv.Section through the level of inferior olivary complex
principal olivary nuc.
Nuc.olivarius accessorius posterior
Nuc. olivarius accessorius med.
accessory cuneate Nuc.

25. Transv.Section through upper levels of medulla
Medial vestibular nuc.
ınf. vestibular nuc.
Gigantocellullar reticular nuc.
Dorsal cochlear nuc.
inferior olivary nuc.
Pyramis
Vagus nerve

26. Transv. Section at teh junction of medulla and Pons
4th Ventricle
Cerebellar nuclei
inf. cerebellar Peduncle
Ventral& dorsal cochlear Nuc.
medial Lemniscus
Arcuate Nuc.