1. MEDIASTINUM
Dr.Kvk

2. Defination:- It is a space between the two pleural cavities.
It is the central compartment of the thoracic cavity.
It contains all the thoracic viscera and structures except the lungs.
It is bounded anteriorly by the sternum,posteriorly by the thoracic vertebrae.

4. DIVISIONS OF MEDIASTINUM
It is divided by an immaginary plane passing through the sternal angle anteriorly and posteriorly by the intervertebral discs between T4 &T5.
This plane is called transverse thoracic plane.
Superior mediastinum lies above this plane.
Inferior mediastinum lies below this plane.

5. INFERIOR MEDIASTINUM
Due to the presence of pericardium and heart it is further divided into:-
Anterior mediastinum,infront of heart
Middle mediastinum,pericardium &heart.
Posterior mediastinum, behind the heart.

6. DIVISION OF MEDIASTINUM
Superior mediastinum,
Middle mediastinum,
Anterior mediastinum,
Posterior mediastinum.

7. Structures in the mediastinum
Thymus gland in children (anterior)
Pericardial sack,heart,vessels(middle)
Esophagus,aorta,thoracic duct,azygos vein(posterior)
Trachea, great vessels(superior)

8. SUPERIOR MEDIASTINUM It lies above the transverse thoracic plane.
It contains aortic arches, thymus, terminal part of S.V.C.,brachiocephalic veins,Trachea and esophagus.

9. Structures in the superior meidiastinum

10. Thymus
Thymus is located in the anterior mediastinum between the pericardium and sternum
Thymus is present only in children
After puberty thymus degenarates

11. Structures in the posterior mediastinum

12. ANTERIOR MEDIASTINUM It contains loose areolar connective tissue,
Lymphatic vessels,
2-3 anterior mediastinal lymph nodes.
Branches of internal mammary artery,
Pulmonary arteries,pulmonary veins,
Phrenic nerves.

13. POSTERIOR MEDIASTINUM
Thoracic part of aorta,
Azygous and hemiazygous veins,
Vagus and splancnic nerves,
Esophagus,
Thoracic duct and lymph nodes.

14. Esophagus &plexus

15. Descending thoracic aorta

16. APPLIED ANATOMY
Tumours arising from thymus,Thymoma compresses the mediastinum.
Pancoast tumour may compress the sympathetic ganglion and cause Horner’s syndrome.
Pericardial effusion-cardiac tamponade due to pericardial effusion.
Hilar group of lymph nodes enlargment leads to dysphagia and dyspnoea.
Compression over recurrent laryngeal nerves lead to hoarseness of voice.

17. Anatomy Lecture
Pericardium

18. Pericardium
Is a double-walled sac that contains the heart and the roots of the great vessels.

19. Layers of pericardium

20. PERICARDIUM Peri= around Cardium= heart It is a fibro-serous sac
which surround the
Heart and the roots
of the large vessels
It consist of:
1- The fibrous pericardium
2-The serous pericardium
two layer:
parietal layer
Visceral layer
3- the sinuses of the pericardium
(transverse – oblique )

21. FIBROUS &SEROUS PERICARDIUM
Fibrous pericardium is made up of dense conective tissue
Inferiorly is connected to diaphragm by percardio phrenic ligament
Interiorly connected to the sternum by sterno pericardial ligament
Superiorly,completely fused with the roots of the great vessels of the heart

22. PLUERA&PERICARDIUM
Most of the pericardium surface is covered pluera the lung except and area posterior to sternum at the level of 4th 5th costal cartilage .
Anteriorly related to anterior mediastinum and thymus in children
Posteriorly related to esophagus,descenting aorta

23. PERICARDIUM&PHRENIC NERVE

25. Formation of pericardial cavity

27. Fibrous and serous pericardium
It is a conical sac which has
Base:
Attached to the central tendon of diaphragm
Apex:
Above the heart to the level of the sternal angle
4- surfaces :
(anterior – posterior – 2 lateral)
Serous
It is a closed serous sac and has
a parietal and
a visceral layer
The visceral layer is called
epicardium

28. PERICARDIUM AFTER REMOVAL OF THE HEART

29. Innervations
The fibrous pericardium and the parietal layer of the serous pericardium are sensory innervated by the phrenic nerves (C3-C5).
The epicardium receives autonomic innervation from the underlying heart

31. Diseases
Pericarditis is inflammation of the pericardium. It can cause fluid to build up in the sac (pericardial effusion).
Excessive amounts of fluid may lead to cardiac tamponade
Pericardio centhesis removal of fluid from the pericardial cavity by inserting a needle

32. THANKYOU
Dr.KUMAR
Associate Professor
thankyou