OBJECTIVETo explore the characteristics of vibration response imaging (VRI) in chronic obstructive pulmonary disease (COPD).

METHODSSixty-three COPD patients received lung function test (LFT) and VRI examination before and after inhalation of bronchodilator. As the control group, 66 healthy volunteers received LFT and VRI examinations. We defined VRI results as quantitative lung data (QLD), crack counts, and image grade.

RESULTSThe results of control group were: QLD of right lung (45.1 +/- 5.9%), mean crack counts 0.1, and mean image grade 0.9. After inhalation of bronchodilator, the VRI results of COPD group were: QLD of right lung (51.0 +/- 12.1)%, mean crack counts 2.7, and image grade 4.2 +/- 1.9. The results between control group and COPD group were significantly different (P < 0.01). The VRI results were similar before and after inhalation of bronchodilator in COPD group (P > 0.05). After inhalation of bronchodilator, there was a linear relationship between VRI image grade and FEV1% (r = 0.31, P = 0.01). The model of the linear regression was: y = 63.85 -2.95 x (y: 100 x FEV1%, x: VRI image grade).

CONCLUSIONSThe VRI results differ between COPD patients and healthy people. The VRI results are stable after inhalation of bronchodilator in COPD patients, which may be helpful in the diagnosis of COPD. The VRI image grade after inhalation of bronchodilator is useful to assess the degree of obstruction.