Learning Radiology xray montage
 
 
 
 
 

Lymphangiomyomatosis and Tuberous Sclerosis
LAM

 

General Considerations

  • Similar in pathology and x-ray appearance
  • Widespread proliferation of smooth muscle in pleura, alveolar septa, bronchi, pulmonary vessels and lymphatics as well as lymph nodes, especially in posterior mediastinum and retroperitoneum
  • Focal emphysema develops as result of narrowing of airways
  • Thoracic duct may be obliterated
  • Produce multiple small cysts with a hamartomatous proliferation of smooth muscle in their walls 

Characteristic imaging triad of:         

  • Progressive, diffuse interstitial disease
  • Recurrent chylous effusions and sometimes chylous ascites
  • Recurrent pneumothorax 
  • Tuberous sclerosis is inherited as a dominant with variable penetrance:
    • Mental defects
    • Epilepsy
    • Retinal phacoma
    • Angiomyolipomas of the kidneys
    • Rhabdomyomas of the heart
    • Intracranial calcifications
    • Sclerotic skull lesions
    • Adenoma sebaceum
    • Subungual fibromas
    • Pulmonary lymphangiomyomatosis (syn:pulmonary myomatosis)
      • Exclusively in females ages 17-47 years
      • Rare

Imaging findings

  • Identical in both tuberous sclerosis and lymphangiomyomatosis and indistinguishable from pulmonary fibrosis except for decreased lung volume in fibrosis and increased lung volume in the others
  • CT
    • Coarse, reticular interstitial pattern
    • Normal/increased lung volume
    • Numerous thin-walled pulmonary cysts and honeycombing
    • Various sizes/surrounded by normal lung parenchyma
  • Unilateral or bilateral pleural effusions which are usually large and recurrent
  • Spontaneous pneumothorax is common 

Clinically

  • Progressive exertional dyspnea and cough
  • Hemoptysis  

 Lymphangiomyomatosis

 
Lymphangiomyomatosis. Note multiple thin-walled cysts throughout both lungs.