The mediastinum is the central compartment of the thorax containing major structures like the heart, great vessels, trachea and esophagus. Pathologies in the mediastinum can include infections, tumors, cysts and lymphadenopathy. Common presentations are due to compression of surrounding structures and include dysphagia, dyspnea, cough and superior vena cava syndrome. Investigations include blood tests, chest X-ray, CT scan, endoscopy and biopsy. Mediastinitis is a life-threatening infection of the mediastinum usually caused by contiguous spread of infection that requires aggressive antibiotic treatment and debridement.

1. THE MEDIASTINUM
Dr Winston Makanga, M.B.Ch.B., M.Med. (Surg)
Consultant General and Laparoscopic Surgeon

2. Outline
• Surgical Anatomy
• Pathology
• Presentation of mediastinal disease
• Investigation
• Overview of mediastinitis

3. Boundaries & divisions
• Superior
• Anterior
• Middle
• Posterior
T4

4. Superior

5. Inferior

7. Major structures
• Thymus
• Tracheo-bronchus
• Esophagus
• Heart and great vessels
• Main branches of the aortic arch
• Azygous , pulmonary vessels
• Sup vena cava and its tributaries

8. Minor structures
• Thoracic ducts
• Lymph nodes
• Sympathetic trunks
• Phrenic nerve
• Vagus

9. Or just classify them by systems…
Cardiovascular
Endocrine
Gastrointestinal
Nervous system
Respiratory
Lymphoid/lymphatic

10. Pathology
• Infections/inflammations
• Reactive lymphadenopathy
• Mediastinitis
• Primary tumors
• Thymoma
• Retrosternal goiter (Thyroid)
• Germ cell tumors (Teratoma)
• Lymphomas**
• Mesenchymal tumors
• Neurogenic tumors
• Cystic lesions
3 Ts of the ant. sup. mediastinum
**Most common ant. Inf. mediastinal tumor

12. Presentation
• Assymptomatic
• Pressure symptoms
• Dysphagia
• Dyspnea
• Cough
• Stridor
• SVC syndrome
• Pain
• Infiltrative symptoms
• Hoarseness of voice
• Pericardial tamponade
• Related to the organ involved

13. Investigation
• Blood: FHG, ESR, CRP
• Chest X-ray
• Widened mediastinum
• Endoscopic ultrasound
• CT scan
• Endoscopy
• OGD
• Bronchoscopy
• Mediastinoscopy
• Sampling
• FNA
• Core biopsy

15. Thymoma
Benign cyst
Teratoma
Thymolipoma

16. Mediastinitis
• Life threatening condition
• Causes
• Contiguous infection (dental, lung)
• Iatrogenic : post cardiothoracic surgery, luminal instrumentation, needle biopsy,
post-surgery of the head and neck, great vessels, or vertebrae
• Trauma: penetrating, esophageal or tracheobronchial perforation by FB
• Presentation: chest pain, fever, high pulse, hypotension, incisional
infection/cellulitis,sternal instability, Hamman sign, pus discharge
• Labs: ↑WBC, CRP, blood and pus MCS, CXR & CT=
pneumomediastinum, AF levels,
• Rx: BS Antibiotics, debridement and wash-out

17. Review
• Anatomy
• Pathology
• Presentation
• Investigation
• Mediastinitis

18. Thanks

19. Presentation
• Superior vena cava syndrome
• Dysphagia
• Stridor
• Chest pain