Mediastinum (ITMIG classification)
The International Thymic Malignancy Interest Group (ITMIG) classification of mediastinal compartments was developed to reflect a division of the mediastinum based on cross-sectional imaging. It was in part an effort to consolidate prior discrepant classification systems in use by different medical specialties. A working group composed of approximately 225 experts in thoracic surgery, medical oncology, diagnostic radiology, and pathology were tasked with forming a practical system for anatomic classification which unified the various systems.
Classification
The ITMIG classification divides the mediastinum into three compartments: prevascular, visceral and paravertebral 1,2.
Prevascular compartment
Boundaries
- superior: thoracic inlet
- inferior: diaphragm
- anterior: posterior cortex of the sternum
- lateral: parietal mediastinal pleura
- posterior: anterior aspect of the pericardium
Contents
- thymus
- lymph nodes
- left brachiocephalic vein
- fat
Visceral compartment
Boundaries
- superior: thoracic inlet
- inferior: diaphragm
- anterior: posterior boundary of the prevascular compartment
- posterior: a vertical line connecting a point on each thoracic vertebral body 1 cm posterior to its anterior margin (visceral-paravertebral compartment boundary line)
Contents
- trachea/carina
- esophagus
- lymph nodes
- heart
- ascending aorta; aortic arch; descending thoracic aorta
- superior vena cava
- intrapericardial pulmonary arteries
- thoracic duct
Paravertebral compartment
Boundaries
- superior: thoracic inlet
- inferior: diaphragm
- anterior: posterior boundaries of the visceral compartment
- posterolateral: vertical line against the posterior margin of the chest wall at the lateral margin of the thoracic spine
Contents
- thoracic spine and paravertebral soft tissues
Related Radiopaedia articles
Anatomy: Thoracic
- thoracic skeleton
- thoracic cage
- thoracic spine
- articulations
- muscles of the thorax
- diaphragm
- intercostal space
- intercostal muscles
- variant anatomy
- spaces of the thorax
- thoracic viscera
- tracheobronchial tree
-
lungs
-
bronchopulmonary segmental anatomy (Boyden Classification) (mnemonic)
- left lung
- right lung
- variant anatomy
- lung parenchyma
- hilum
- pleura
-
bronchopulmonary segmental anatomy (Boyden Classification) (mnemonic)
-
heart
- cardiac chambers
- heart valves
- pectinate muscles
- cardiac fibrous skeleton
-
coronary arteries
- coronary arterial dominance
- myocardial segments
-
left main coronary artery (LMCA)
- ramus intermedius artery (RI)
-
circumflex artery (LCx)
- obtuse marginal branches (OM1, OM2, etc))
- Kugel's artery
-
left anterior descending artery (LAD)
- diagonal branches (D1, D2, etc)
- septal perforators (S1, S2, etc)
-
right coronary artery (RCA)
- conus artery
- sinoatrial nodal artery
- acute marginal branches (AM1, AM2, etc)
- inferior interventricular artery (PDA)
- posterior left ventricular artery (PLV)
- congenital anomalies
- innervation of the heart
- fetal circulation
-
pericardium
- pericardial space
- oblique pericardial sinus
- transverse pericardial sinus
-
pericardial recesses
- aortic recesses
- pulmonic recesses
- postcaval recess
- pulmonary venous recesses
- pericardial ligaments
- epicardial fat pad
- esophagus
- thymus
- breast
- blood supply of the thorax
- arteries
- veins
- superior vena cava (SVC)
- inferior vena cava (IVC)
-
coronary veins
- cardiac veins which drain into the coronary sinus
- great cardiac vein
- middle cardiac vein
- small cardiac vein
- posterior vein of the left ventricle
- vein of Marshall (oblique vein of the left atrium)
- anterior cardiac veins
- venae cordis minimae (smallest cardiac veins or thebesian veins)
- cardiac veins which drain into the coronary sinus
- pulmonary veins
- thoracoepigastric vein
- lymphatics
- innervation of the thorax