Aerosol-derived airway morphometry and aerosol bolus dispersion in patients with lung fibrosis and lung emphysema.
OBJECTIVE
Patients with lung emphysema show increased aerosol-derived dimensions of peripheral airspaces and increased aerosol bolus dispersion (AD). To apply these tests in epidemiologic studies, the objective of this pilot study was to investigate whether morphometric changes caused by lung fibrosis can be distinguished from those caused by emphysema.


METHODS
This study was designed as a cross-sectional study in which airspace dimensions and AD in patients with emphysema and in patients with fibrosis were compared. Forty patients participated in the study: 20 patients had high-resolution CT (HRCT)-proved lung emphysema and 20 patients had HRCT-proved lung fibrosis. All patients underwent conventional lung function tests, aerosol-derived airway morphometry (ADAM), and AD measurements.


RESULTS
Patients with lung emphysema showed normal dimensions of small airways but enlarged airspace dimensions in the lung periphery. Patients with fibrosis showed in all lung depths increased airspace dimensions. AD was increased in patients with emphysema but was normal in patients with fibrosis.


CONCLUSIONS
These results show that when using ADAM and AD, morphometric changes caused by emphysema can be distinguished from those caused by fibrosis with high sensitivity and specificity.
Brand
P
P
Clinical Research Group Aerosols in Medicine of the GSF National Research Center for Environment and Health, Institute for Inhalation Biology and the Clinic for Respiratory Medicine, Gauting, Germany. BRAND@GSF.DE
Kohlhäufl
M
M
Meyer
T
T
Selzer
T
T
Heyder
J
J
Häussinger
K
K
D000328:Adult; D000336:Aerosols; D000403:Airway Resistance / Q000502:physiology*; D002908:Chronic Disease; D003430:Cross-Sectional Studies; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008168:Lung / Q000473:pathology*; D008297:Male; D010865:Pilot Projects; D011656:Pulmonary Emphysema / Q000473:pathology* / Q000503:physiopathology; D011658:Pulmonary Fibrosis / Q000473:pathology* / Q000503:physiopathology; D012129:Respiratory Function Tests; D012680:Sensitivity and Specificity
D000336:Aerosols