1 بسم الله الرحمن الرحيم

2 By : Pulmonary Medicine Department Ain Shams University telemed.shams.edu.eg/moodle5

At the end of this lecture the student should be able to: 1.Describe the anatomy of the mediastinum. 2.Distinguish the mediastinal space occupying lesions and site of appearance. 3.Discuss the clinical picture including mediastinal syndrome. 4.Interpret the investigations including computed tomograpghy. 5.Predict the diagnosis and discuss the diagnostic interventions including imaging-guided biopsy. 6.Describe the different treatment modalities. 3

4 The mediastinum is the region between the 2 pleural sacs. It extends from the thoracic inlet to the diaphragm, and from the sternum to the spine. It is maintained in the central position by a balance between the pleural pressures on both side. In infants and children the mediastinum is highly mobile. Later in life, it becomes more rigid, so that unilateral changes in pleural pressure have less effect on its mobility.

5 Cont….

6

7

8 (1)Superior mediastinum : it contains Aortic arch & its 3 branches S.V.C. & its 2 innominate veins Trachea, esophagus, thoracic duct Vagus, phrenic n., left recurrent laryngeal n. and sympathetic n. L.N. & thymus. Divisions of the mediastinum :

9 (2) Anterior mediastinum : Boundary: Anterior Sternum Posterior Pericardium Contents: Thymus L.N. Fatty tissue Cont….

10 (3) Middle mediastinum: Boundary : By the 3 divisions. Contents : Heart & pericardium Ascending aorta, S.V.C & I.V.C. Pulmonary arteries & veins Tracheal bifurcation Phrenic nerves Cont….

11 (4) Posterior mediastinum : Boundary : Anterior pericardium & diaphragm Posterior lower 8 thoracic vertebrae Contents : Descending aorta Esophagus Sympathetic & vagus nerves Thoracic duct L.N. Cont….

12 (A) Superior mediastinum : Thymic tumors Intrathoracic thyroid Teratoma Esophageal lesions Cystic hygroma Lymphomata Mediastinal abscess

13 Thymic tumor

14

15

16 X-ray showing enlarged mediastinal Lymph nodes in Hodgkin’s disease. Cont….

17 Intrathoracic thyroid displacing the esophagus to the left ( barium swallow )). Cont….

18 Cont…. Cystic hygroma

19 (B) Anterior mediastinum : Thymic tumors & cysts Teratoma Intrathoracic thyroid Cystic hygroma Pleuro-pericardial cyst Lymphomata Cont….

20 X-ray of a large anterior mediastinal mass Cont….

21 (C) Middle mediastinum : Aortic aneurysm Anomalies of great vessels Bronchogenic cyst Lipoma Cont….

22 (d) Posterior mediastinum : Neurogenic tumors Gastroenteric & bronchogenic cysts Esophageal lesions Meningocele Aortic aneurysm Cold abscess Hernia through foramina of Bochdalek Cont….

23 This is usually results from compression of the mediastinal structures by a mediastinal lesion. Causes : Mediastinal tumors Chronic mediastinitis Mediastinal emphysema

24 Primary location of specific neoplasma & cysts within the subdivisions of the mediastinum Cont….

25 1) Pressure symptoms 2) Hormonal effects These depend on : * Site of lesion * Structure involved Cont…. Manifestations :

26 Pressure symptoms : Esophagus : dysphagia. Trachea & bronchi : brassy cough, stridor, obstructive emphysema or atelectasis Arteries : unequal pulse, ischaemic manifestations ( pallor, pain and syncope ). Cont….

27 Veins : usually S.V.C distension of neck veins, collaterals. Nerves : * Sympathetic Horner’s syndrome. * Vagus dysphagia & arrhythmia. * Recurrent laryngeal hoarseness of voice. * Phrenic diaphragmatic paralysis. Cont….

28 Hormonal : Retrosternal goiter Toxic changes Thymic tumor Myasthenia gravis Parathyroid adenoma Hyperparathyroidism Cont….

29 S.V.C.obstruction, note the swollen arms and the tortuous collaterals over the anterior chest wall Cont….

30 S.V.C. obstruction Cont….

31 Horner’s syndrome. Note ptosis & constricted pupil. Cont….

32 Brachial plexus affection. Cont….

33 Myasthenia gravis. This is common with Thymic tumors. Cont….

34 Causes : (1)Esophageal perforation: * Traumatic : endoscopies, dilatation, intubations * Spontaneous (2)Operation : in the larynx, trachea, esophagus (3)Suppurative L.N. secondary to infection of the lung, esophagus & larynx.

35 (5)Direct extension of infection from the neck, retropharyneal space, pleura, pericardium. (4)T.B, osteomyelitis of cervical or thoracic spine. Cont….

36 Clinical features : Substernal pain Rigors Fever Neck pain Torticollis Brassy cough ( if trachea is involved ) Cont….

37 O / E : Toxic Cyanosis Restless Anxious Tenderness over the sternum WBCs : leucocytosis Pleural effusion or pyopenumothorax Mediastinal emphysema Cont….

38 X –Ray May be normal or, if fluid or pus is collecting in the mediastinum, a smooth walled convex opacity may be seen bulging laterally beyond the mediastinal boundaries. Pleural effusion, mediastinal emphysema, pyopneumothorax. Cont….

39 A mediastinal abscess following a perforation of the esophagus Cont….

40 Treatment : Broad spectrum antibiotics. Abscess: surgical drainage. Cont….

41 Other names include:  Chronic fibrous or fibrosing mediastinitis,  Idiopathic mediastinal fibrosis, and  Chronic mediastinal fibrosis.

42 Cont…. Etiology : Unknown, theories T.B & Syphilis Keloid Autoimmune Histoplasmosis Methysergide Due to stimuli: infective, traumatic, toxic, immunologic Idiopathic.

43 Pathology : Masses of ill-defined tissue encase and may compress the mediastinal structures. Histology shows that the predominant feature is the presence of bundles of hypocellular collagenous tissue containing an infiltrate of plasma cells with some lymphocytes, polymorphs and fibroblasts. Cont….

44 Clinical picture : Age : any age, but common in 4 th decade. Sex : males & females are equally affected. Onset : insidious. Site : * S.V.Cava obstruction is mainly present, but also the innominate & azygos veins can be affected. * Veins of upper limb may be affected to a lesser extent. Cont….

45 S.V.C.obstruction, note the swollen arms and tortuous collaterals Cont….

46 S.V.C obstruction, dilated veins on front of chest Cont….

47 Appearance : The face & neck begin to swell especially when the patient stoop or lies down. Later swelling of eye lids & subconjunctival edema Headache, breathlessness & epistaxis which become worse on coughing,straining or exercise. Cont….

48 As time passes collateral venous channels appear, which allows features to undergo slow improvement. Stricture of pulmonary veins, trachea, main bronchi. Cont….

49 X - Ray : Nothing characteristic Widening of upper mediastinum Tomography: tracheobroncheal stricture Barium swallow: esophageal stricture Angiography. Cont….

50 Mediastinal widening in idiopathic mediastinal fibrosis Cont….

51 Treatment : Stop drugs: Methysergide Surgical removal S.V.Cava bypass Stricture of esophagus: dilatation Corticosteroid ?????? Cont….

52 Def. : Air in the mediastinal tissues. Etiology & Pathogenesis : The air enter the mediastinum from: Ruptured bronchus Ruptured esophagus Indirectly along the perivascular sheath of pulmonary vessels, following rupture of alveoli Through the retro peritoneal tissue, in rare cases following rupture of some part of GIT, or perianal insufflations

53 Precipitating factor Rupture of alveoli is usually ppt. By straining with the breath held in inspiration: labour or any lung disease in which airway obstruction is combined with cough. In newborn, rupture of alveoli or congenital cyst. This may occur in resuscitation of apneic infant. Cont….

54 Endoscopy Spontaneous rupture of esophagus The air may escape:- a) Upwards into s.c tissue of neck b) Downwards into retroperitoneal tissue Cont….

55 Clinical picture : Ruptured bronchus: 2/3 accompanied with pneumothorax. Ruptured esophagus: pleural effusion. However most of cases is symptomless, sometimes the patient feels crepitus. When air accumulate in the mediastinal tissue  compression effect  pain like myocardial infarction dyspnea, cyanosis, hypotension. Cont….

56 Surgical emphysema of the face. Cont…. Same patient after 2 weeks

57 O / E : Absence of cardiac dullness. Hamman’s sign: a crepitus, crackling or crunching sound heard with the stethoscope, synchronous with systole. On rare occasions sufficient air surround the heart and caused cardiac tamponade with breathlessness, cyanosis and hypotension. Fever may indicate the onset of mediastinitis Cont….

58 X- Ray : Arc shaped translucency scalloping the outline of upper mediastinum, and air may outline the heart border especially the left border Air in the soft tissue surgical emphysema Lateral view neck  air Pneumothorax & or pleural effusion Cont….

59 Air appears as a narrow translucent halo outlining the heart and aortic arch Cont….

60 Treatment : Treatment of the cause Assurance & resuscitation O2 therapy Skin incision above suprasternal notch Cont….

61 End