Citation, DOI & article data
Gravity-dependent atelectasis refers to a form of lung atelectasis which occurs in the dependent portions of the lungs due to a combination of reduced alveolar volume and increased perfusion. Being due to gravity, it usually has a dependent and subpleural distribution. It is very commonly seen in the posterior lung bases on CT, particularly in elderly individuals.
In normal lung, gravity gradients exist in end-inspiration between the apex and lung base of 4:1 in the erect patient and between the anterior and posterior lung of 2.5:1 in the supine patient 1. These gradients increase in the presence of lung disease that increases the weight of the lung causing atelectasis.
- bedridden patients
- patients with prolonged shallow breathing
- impaired mucociliary clearance
- pulmonary edema
- 1. Woodring JH, Reed JC. Types and mechanisms of pulmonary atelectasis. (1996) Journal of thoracic imaging. 11 (2): 92-108. Pubmed
- 2. Kashiwabara K, Kohshi S. Additional computed tomography scans in the prone position to distinguish early interstitial lung disease from dependent density on helical computed tomography screening patient characteristics. (2006) Respirology (Carlton, Vic.). 11 (4): 482-7. doi:10.1111/j.1440-1843.2006.00869.x - Pubmed