Mizuki Nishino MD, Presenter: Nothing to Disclose

Bettina Siewert, Abstract Co-Author: Nothing to Disclose

David H. Roberts, Abstract Co-Author: Nothing to Disclose

Phillip Michael Boiselle MD, Abstract Co-Author: Nothing to Disclose

Vassilios D. Raptopoulos MD, Abstract Co-Author: Nothing to Disclose

Hiroto Hatabu MD, PhD, Abstract Co-Author: Nothing to Disclose

To evaluate the frequency and severity of bronchomalacia, defined as excessive collapsibility of bronchi, in patients with bronchiectasis; to compare the extent of air trapping in patients with/without bronchomalacia; and to correlate the severity of bronchomalacia and the extent of air trapping versus pulmonary function test results.

46 patients with clinical diagnosis of bronchiectasis evaluated by volumetric expiratory high-resolution CT and pulmonary function tests within 2 weeks of the CT scans were studied. The presence and severity of bronchomalacia were evaluated on contiguous axial high-resolution CT images using a four-point scale: 0=none; 1=mild; 2=moderate; 3=severe. The extent of air trapping was qualitatively graded on coronal reformatted images, using a five-point scale: 0= 0%, 1= 1-25%, 2= 26%-50%, 3= 51%-75%, 4= 76%-100%, independently from assessment of bronchomalacia. Differences in the extent of air trapping in patients with/without bronchomalacia and the correlation between the severity of bronchomalacia and the extent of air trapping were investigated using a chi-squared test. The severity of bronchomalacia and the extent of air trapping were correlated with pulmonary function test results using Mann-Whitney U test.

Of 46 patients with bronchiectasis, 32 patients (70%) had bronchomalacia at end-expiration. Air trapping was present in 43 patients (93%). The extent of air trapping in patients with bronchomalacia was significantly greater compared to the patients without bronchomalacia (p=0.0308, chi-squared test). While the correlation between the severity of bronchomalacia and extent of air trapping was not statistically significant, it did however show a trend (p=0.1410, chi-squared test). Neither the severity of bronchomalacia nor the extent of air trapping showed significant correlation with pulmonary function.

The extent of air trapping in bronchiectasis patients with bronchomalacia was significantly greater compared to that in bronchiectasis patients without bronchomalacia. These results suggest that bronchomalacia is one of the underlying mechanisms of air trapping in bronchiectasis.

Nishino, M, Siewert, B, Roberts, D, Boiselle, P, Raptopoulos, V, Hatabu, H, Excessive Collapsibility of Bronchi in Bronchiectasis: Evaluation on Volumetric Expiratory High-Resolution CT with Functional Correlation.  Radiological Society of North America 2005 Scientific Assembly and Annual Meeting, November 27 - December 2, 2005 ,Chicago IL. http://archive.rsna.org/2005/4406156.html