Mediastinoscopy

Learning objectives

Mediastinoscopy is a diagnostic procedure with high sensitivity and specificity for lung cancer staging
Also used for biopsy of mediastinal masses and diagnosis in diseases presenting with mediastinal lymphadenopathy
The majority of mediastinoscopies are performed via the cervical approach:
- Entering the mediastinum through a 3 cm incision in the suprasternal notch
- A dissection is made between the left innominate vein and the sternum creating a tunnel in the fascial layers
- The mediastinoscope is then inserted anterior to the aortic arch

Indications
- Evaluation of lymph node involvement in patients with carcinoma of the lung
- Tissue biopsy of mediastinal masses
- Removal of mediastinal masses and enlarged lymph nodes
  - Conditions presenting as a mediastinal mass:

Tumors	Anterior mediastinum	Thymic tumors
		Thyroid and parathyroid tumors
		Lymphoma
		Germ cell tumors
	Middle mediastinum	Lymphoma
		Mesenchymal tumors
	Posterior mediastinum	Esophageal cancer
		Neurogenic tumors
Benign conditions	Developmental cysts	Pericardial cyst
		Esophageal cyst
	Granulomatous lymphadenopathy	Tuberculosis
		Sarcoidosis
	Vascular	Aneurysms (e.g., thoracic aorta, innominate vein)
		Aberrant vessels (e.g., persistent left superior vena cava, anomalous left pulmonary artery

Absolute	Anterior mediastinal mass
	Inoperable tumor
	Previous recurrent laryngeal nerve injury
	Extremely debilitated patients
	Ascending aortic aneurysm
	Previous mediastinoscopy
Relative	Thoracic inlet obstruction
	SVC syndrome
	Severe tracheal deviation
	History of radiation therapy to the chest
	Cerebrovascular disease
	Severe cervical spine disease with limited neck extension
	Thoracic aortic aneurysm