LESSON #20 (6 HOURS)
Theme. Brainstem. Medulla oblongata (external and internal structure). Pons. Reticular formation. Cerebellum (external and internal structure, nuclei and peduncles). Rhomboencephali isthmus. Fourth ventricle. Rhomboid fossa (topography of cranial nerves nuclei).
Midbrain: tectum, cerebral peduncles, cerebral aqueduct
Aіm: Study the structural and topographical peculіarіtіes of the medulla oblongata and pons, the topography of white and gray matter, peculiarities of the reticular formation. To study the structure of metencephalon, isthmus rhombencephali, ventriculus quartus (IV), the relief of romboid fossa. Topography of nuclei of cranial nerves.
To learn the structure of mesencephalon and its cavity. To know the structure, borders of mesencephalon, tegmen, pedunculi, aqueduct. To observe the anatomic structures of internal structure of mesencephalon: lamina of tegmen and pedunculus of cord. The topography of oculomotor and throchlear nuclei and nerves.
The professіonal orіentatіon. Knowledge the external and internal structure of the medulla oblongata and pons is necessary for neurological therapy and surgery in brain. Anatomical peculiarities of the localization of regulator centers and nucleus are base for understanding of neurophysiology and neuropathology, also in traumatology. Data concerning structure of the cerebellum and fourth ventricle, especially topography of nuclei and functional centres of motor co-ordination, breathing, blood circulation and others, is the base for studying physiology of nervous processes. Knowledge the ways of nervous impulses explains us mechanism of pathology during neurological diseases.
Data concerning topography of nuclei Rhomboid fossa is the base for studying physiology of nervous processes and understanding the structure and innervating role of V-XII cranial nerves. Anatomical peculiarities of the localisation of regulator centres and nucleus are base for understanding neuropathology and traumatology.
Pay attention to this part of central nervous system in phylogenesis that develops by influence of visual receptor, that is the reason why these structures are related to visual organ. There are subcortical centres of hearing that with visual centres are situated in corpus quadrigemina. There are the following structures of mesencephalon: subcortical centres of vision and nuclei of nerves that innervate the muscles of eye, subcortical centres of hearing, descending and ascending ways, that connect the cortex with spinal cord.
Base level of knowledge and skіlls
1. Latіn termіnology.
2. Structure of Skull.
I. I. Practical work – 9:00-12:00 am (4 hours)
1) Іllustratіve materіal
1. Preparation of brainstem.
2. Preparation of cerebellum.
3. Cross section through of the midbrain.
4. Plate ‘Rhomboid fossa’.
2) Methods of practical work
Task 1. Under the supervision of the teacher make the preparation of the brainstem.
Task 2. Make the preparation of the rhomboid fossa.
Task 3. Schematically draw the nuclei of the pons.
Task 4. Make the preparations of dentate nucleus. Thus, make horizontal section on the cerebellum on different levels.
Task 5. Schematically draw the cerebellar nuclei.
Task 6. Make a preparation of the IV ventricle. Make sagittal section across cerebrum trunk.
Task 7. Under teacher’s supervision make the preparation of the rhomboid fossa.
Task 8. Draw the scheme of the rhomboid fossa and draw the projection of the cranial nerves’ nuclei on it.
Task 9. Under teacher’s supervision make the preparation of the midbrain.
Task 10. Draw the scheme of the midbrain section.
· Practical skills and abilities of students, demonstrate on preparations:
Special attention should be paid to the following:
1. Medulla oblongata: pyramis, oliva, site of exit of n. abducens, n. facialis, n. vestibulocochlearix, n. glassopharyngeus, n. vagus, n. accesorius n. Hypoglossus.
2. Brainstem and medulla oblongata: the shape, the length and the borders of medulla oblongata, the relief of anterior and posterior surfaces of medulla ablongata, sulci and fasciculi, tuberculi (gracilis and cuneatus) substantia grisea: nucleus olivaris, formatio reticularis, nuclei of nn. glossopharyngeus, vagus, accessorius, hypoglossus. Nucleus cuneatus, the centers of medulla oblongata. Cavitas ventriculi quarti (IV).
3. Substantia alba: pyramides (funiculi anteriores), lateral and posterior funiculi, decussatio peramidum, fasciculi gracillis and cuneatus, pedunculi cerebellaris inferiores, lemniscus medialis, decussatio.
4. The shape, borders and external structure of the pons. The division of pons into two parts. Corpus trapezoideum and its dorsal nucleus. Tectum and the basis of the pons. Nuclei of V, VI, VII, VIII cranial nerves. Fibers of lemniscus medialis et lateralis. Reticular formation.
The cerebellum: its shape and size. The division of cerebellum into parts. The surfaces, borders, fissure and gyri cerebellum. Lobes and lobules of vermis and hemispheres. Pedunculi cerebelli inferiores, medii, superiores. Structure of the cortex, nuclei, arbor vitae.
5. Isthmus rhombencephali: trigonum lemnisci, vellum medullare superius, pedunculi cerebelli superiores, their structure and morpho-functional importance.
6. Ventriculus quartus (IV): tegmen ventriculi quarti, velum medullare superius, tela choroidea ventriculi quarti. Aperturae mediana and laterales ventriculi quarti, fossa rhomboidea, striae medullares ventriculi quarti.
7. Borders of rhomboid fossa: pedunculi cerebry interior, pedunculi cerebri medii, lateral angles, which form lateral pockets of IV ventricle. The relief of rhomboid fossa: sulcus medianus, paired median eminentia, stria medullare, facial tubercle, cranial and caudal fossae. Blue place, vestibular area, triangles of vagus and sublingual nerves.
8. Table-scheme of rhomboid fossa.
9. V trigeminal nerve has nuclei: 1 - motor nucleus of trigeminal nerve; 2, 3, - sensitive nucleus, which consist from two parts: a) pontinus nucleus of trigeminal nerve; b) nucleus of spinal tract of trigeminal nerve; c) nucleus of mesencephalicus tract.
4. VI (nervus abducens) has one nucleus of nervus abducens;
5. VII (facial nerve) has three huclei. 1- Nucleus of facial nerve, motor. 2- Nucleus solitarius, common for VII, IX, X pairs of cranial nerves. Nucleus salivatorius superior (vegetative, parasympathetic).
6. VIII (vestibulocochlear nerve) has 2 pares of nuclei: two acoustic and pour vestibule nuclei.
A) Acoustic nuclei: 1. Anterior acoustic nucleus. 2. Posterior acoustic nucleus.
B) Vestibular nuclei: 1. Medial vestibular nucleus (nucleus of shvalbe). 2. Lateral vestibular nucleus (nucleus of Deiters). 3. Superior vestibular nucleus (nucleus of Bechtereva). 4. Interior vestibular nucleus (nucleus of Roller).
7. IX (glossopharyngeal nerve) has three nuclei:
8. Ambiguous nucleus - motor, common with X pare of cranial nerves. . 2- Nucleus solitarius, common for VII, IX, X pairs of cranial nerves.3. Nucleus salivatorins interior, vegetative, parasympathetic.
X (vagus nerve) has three nuclei: 1. Ambiguous nucleus, motor, common for IX and X cranial nerves. 2. Nucleus solitarius, common for VII and IX pairs of nerves, sensitive. 3. Posterior nucleus of vagus nerve, parasympathetic.
XI accessories nerve has motor nucleus, which continues in spinal cord.
XII hypoglossus nerve has hypoglossus motor nucleus in hypoglossal triangle.
II. Seminar discussion 12:30 am – 14:00 pm (2 hours)
Where is located dentate nucleus:
A Medulla oblongata
D Rhomboid fossa
Indicate position of gracilis nucleus:
F Medulla oblongata
I Rhomboid fossa
Where is located red nucleus:
K Medulla oblongata
N Rhomboid fossa
Where is located Rhomboid fossa:
P On Medulla oblongata and spinal cord
Q On Medulla oblongata and cerebellum
R On Medulla oblongata and pons
S On Pons and midbrain
T On Pons and isthmus rhomboencephali
· Discussion of theoretical questions:
1. What does develop of the rhombencephalon.
2. Show on the basis of the cerebrum the sites of exit of V-XII cranial nerves.
3. Describe the superior and inferior borders of medulla oblongata.
4. What surfaces does medulla oblongata have?
5. What structures are located on the ventral, dorsal and lateral surfaces of medulla oblongata?
6. Which nuclei of cranial nerves are in the medulla oblongata?
7. Describe the superior and inferior borders of pons.
8. Describe the shape, borders and external structure of Pons.
9. Describe internal structure of the pons.
10. Which nuclei are in the pons?
11. Describe the peculiarities of localisation and structure of reticular formation.
12. Describe the function of reticular formation.
13. What parts does the cerebellum have?
14. What pedunculi does the cerebellum have?
15. Name and show the nuclei of cerebellum.
16. Where we can see “arbor vitae cerebelli”?
17. What is the tegmen ventriculi quarti formed by?
18. What is the fundus ventriculi quarti formed by?
19. What does ventriculus quartus connect with?
20. What does produce cerebrospinal fluid?
21. Name and show, what does belong to isthmus rhombencephali?
22. What is the source for development of mesencephalon?
23. What are the components of mesencephalon?
24. What is the cavity of mesencephalon?
25. What does the mesencephalon connect with?
26. Describe the structure of mesencephalon in frontal section.
27. What centres are situated in superior and interior tubercles?
28. What nuclei are located in corpus quadrigemina?
ІІІ. Independent students work – 14:15pm – 15:00 pm
1. Atlas of Human Anatomy/ Frank H. Netter,- 5 edition, - 2011 by Saunders, an Imprint of Elsevior Inc.
2. Gray's Anatomy for Students: With STUDENT CONSULT Online Access, 2e, - 2010. 2092 p. Richard L. Drake Ph.D, A. Wayne Vogl, Adam W.M. Mitchell, – Printed in Canada.
3. Materials preparation for lectures
4. Materials preparation for practical classes
1. Human anatomy & physiology /Elaine N. Marieb, Katja Hoehn., San Francisco : Benjamin Cummings, c2010., 8th ed.
2. F.H. Netter. Atlas of Human Anatomy. – Cіba Pharmaceutіcals Dіvіsіon, 1994. – 514 p.
3. Synelnіkov R.D. The atlas of anatomy of the man. Іn 4-th volumes. -: Medіcіna, 1991.
4. Reminetskyy B.Y., Fedonyuk Y.I. Human anatomy. Notes. 136 p.
The instruction was discussed and confirmed at the department meeting
25.06.2012. Protocol number 11