Anatomy and Surgical Approaches to the Mediastinum Flashcards
Boundaries of mediastinum
- Sternum (anterior)
- Spine (posterior)
- Thoracic inlet (superior)
- Diaphragm (inferior)
- Pleurae (laterally)
Boundaries and structures of Anterior compartment
- Sternum (anterior)
- Great vessels and percardium (posterior)
- Contents:
- Thymus
- Internal mammary arteries
- Adipose tissue
Boundaries and structures of Middle Compartment
- Great vessels and pericardium (anterior)
- Anterior surface of thoracic spine (posterior)
- Contents:
- Great vessels
- Pericardium
- Heart
- Trachea
- Proximal main stem bronchi
- Vagus and phrenic nerves
- Esophagus
- Thoracic Duct
- Descending Aorta
Boundaries and stuctures of the Posterior Compartment
- Mostly a potential space that lies laterally along spine
- Contents:
- Sympathetic chain + ganglia
- Intercostal neurovascular bundles
Definition of Medistinal LN levels
Levels 1-9
(contained in mediastinal pleura)
Surgical options for mediastinal access
- Cervical mediastinosopy
- Anterior mediastinoscopy (Left side = Chamberlain procedure)
- Median sternotomy
- Transcervical approach
- Bilateral thoracosternotomy (Clamshell)
- Unilateral thoracosternotomy (Hemi-clamshell)
- VATS
MC indication for MLN biopsy
Assess for N2 nodal involvement in stage I-III NSCLC
Rationale for pursuing MLN sampling for NSCLC
5% false-negative rate to detect MLN mets with PET/CT
Other indications for MLN biopsy
- Tissue diagnosis in setting of mediastinal lymphadenopathy (sarcoid, lymphoma)
- Biopsy mediastinal masses
Relative contraindications to cervical mediastinoscopy
- Severe kyphosis of c-spine
- tracheostomy
- Large thyroid goiter
- Aortic arch or innominate artery aneurysm
Cervical mediastinoscopy should not be performed in the presence of what conditions
SVC syndrome (high risk of bleeding)
Significant innominate artery calcifications (high risk of embolic stroke)
MLN levels accessible during cervical mediastinoscopy
Levels 2,4,7
MC complications of cervical mediastinoscopy
- Major bleeding (0.1-0.6%)
- RLN injury (0.5%)
- Pneumothorax
- Airway injury
- Esophageal perforation
MC biopsy site associated with major hemorrhage during cervical mediastinoscpy
Station 4R
(injury to azygous or SVC)
2nd MC biopsy site associated with major bleeding during cervical mediastinoscopy
Station 7
(RPA and bronchial artery bleeding)