bronchopleural fistula

Bronchopleural fistulas are communications between the bronchial tree and the pleural space.

Pathology

They are usually divided as:

  • central: when the fistula involves the trachea or a lobar bronchus
  • peripheral: when a distal airway, either segmental bronchi or the lung parenchyma, communicates to the pleural space
Etiology
  • postoperative complication of pulmonary resection: considered by far the most common cause, with a reported incidence from 1.5 to 28% after pulmonary resection
  • lung necrosis complicating infection or infarction
  • traumatic
    • pneumatoceles 
    • iatrogenic (eg. thoracic tube insertion, lung biopsy, toracocentesis, and nasogastric tube malpositioning)
  • lung neoplasms
    • tumor extension into the pleural space
    • tumor necrosis after chemotherapy or radiotherapy

Radiographic features

Plain radiograph

On chest radiography, the features that may be seen include:

  • steady increase in intrapleural airspace
  • appearance of a new intrapleural gas-pleural fluid collection - i.e. a hydropneumothorax. The gas-fluid level typically extends to the chest wall and shows unequal linear dimensions on orthogonal views conforming to the pleural space
  • changes in an already present gas-fluid level
  • development of tension pneumothorax
  • a drop in the gas-fluid level exceeding 2 cm (if the patient has no chest tube in place)
CT

CT is considered the imaging technique of choice for visualizing and characterizing bronchopleural fistulae . CT may show:

Nuclear medicine

Radioaerosol scanning (e.g. xenon ventilation nuclear scintigraphy) has been successfully used in the evaluation of bronchopleural fistulas. A variety of radioactive tracers may be used, including:

  • technetium-99m (99mTc) albumin colloid fog inhalation
  • 99mTc sulfur colloid
  • 99mTc-labeled diethylenetriamine pentaacetate, krypton, and xenon
  • single photon emission tomography using radiolabeled aerosol inhalation. If there is fistula the radioactive tracer will equilibrate between the postpneumonectomy or pleural space and the airways after inhalation