Opaque hemithorax with ipsilateral mediastinal shift


  • A 66 years old man
  • Presented with chronic cough and worsening shortness of breath
  • Associated with constitutional symptoms
Chest radiograph in PA erect view

Radiographic findings:

  • There is opacity of the whole left hemithorax.
  • Obliteration of cardiac outline and left hemidiaphragm.
  • There is tracheal and mediastinal shift to the same side.
  • Abrupt termination of the left bronchus shadow with soft tissue opacity within it (white arrow).
  • Compensatory hyperinflation of the right lung (yellow arrows).
  • Right lung is well aerated. No lung nodule or mass in the right lung.
  • No pleural effusion or pneumothorax on the right side.
  • Bones are unremarkable.

Radiologic diagnosis: Opaque left hemithorax with ipsilateral mediastinal shift


  • Complete opacification of a hemithorax on chest X-ray is termed opaque hemithorax
  • The differential diagnosis of an opaque hemithorax is primarily based on the volume of the affected hemithorax, as determined by the position of the mediastinum
    • increased hemithoracic volume-mediastinal shift to the unaffected side
    • reduced hemithoracic volume-mediastinal shift to the affected side
    • normal hemithoracic volume-no mediastinal shift
  • The differential diagnosis of an opaque hemithorax with reduced ipsilateral volume and ipsilateral mediastinal shift includes pulmonary agenesis, pneumonectomy, and atelectasis. Bronchial obstruction by a foreign body (in children) or an endobronchial tumor (in adults) is the most common cause of atelectasis/lung collapsed.

Progress of patient:

  • CT scan performed
  • Biopsy showed Non-small cell lung carcinoma
CT scan thorax, post contrast in axial plane; (a-c) soft tissue window and (d-f) lung window

CT scan findings:

  • There is soft tissuel lesion seen extending into and causing total obliteration of distal left main bronchus.
  • There is total collapsed of the left lung.
  • Multiple ill-defined relatively hypodense lesions within the collapsed left lung could represent lung nodules.
  • There is ipsilateral shift of the trachea, mediastinum and heart.
  • Minimal left pleural effusion is seen. No pleural thickening or abnormal enhancement.
  • Right lung field is well aerated with no focal lesion seen within it.
  • There is no pericardial effusion. Heart is not enlarged.
  • There are a few mediastinal nodes seen.



Author: radhianahassan