Learning Radiology xray montage

Superior Vena Caval Obstruction
Superior Vena Caval Syndrome



General Considerations

  • Obstruction of flow in the superior vena cava due to:
    • Most often due to thoracic malignancy, especially small-cell carcinoma
    • Large-cell type of non-Hodgkin lymphoma
    • Intravascular thrombosis indwelling catheters
    • Mediastinal fibrosis
    • Infections such as TB and histoplasmosis
  • May produce superior vena caval syndrome
  • Obstruction of the SVC results in one or more collateral pathways (60% or more narrowing)
    • The azygous venous system, which includes the azygos vein, the hemiazygos vein, and the connecting intercostal veins
    • The internal mammary venous system plus tributaries and secondary communications to the superior and inferior epigastric veins
    • The long thoracic venous system, with its connections to the femoral veins and vertebral veins, provides the third and fourth collateral routes.

Clinical Findings

  • Symptoms depend, in large measure, on how quickly the obstruction develops and the efficiency of the collaterals that are able to form
  • Dyspnea is the most common symptom
  • Facial swelling
  • Cough
  • Arm swelling
  • Hoarseness
  • Stridor

Imaging Findings

  • Chest radiography
    • Mediastinal or right upper lobe mass
  • CT is the study of choice
    • Mediastinal mass
    • Narrowing or complete obstruction of the SVC
    • Collateral flow
  • Venography is the most conclusive study


  • Relieve symptoms with oxygen, diuretics, elevation of the head
  • Treat the primary malignancy, if present
  • Thrombolysis, if indicated


  • Depends on the underlying cause of the obstruction

Superior vena Caval Obstruction 


 Superior vena Caval Obstruction. There is a mediastinal soft tissue mass (white arrows) that is completely obstructing the superior vena cava, the location of which is marked by a red arrow.

Superior Vena Cava Syndrome Treatment and Management. TA Nickloes, AM Kallab, and LO Mack. eMedicine.