The measurement of "closing volume" as affected by lung volume at tracer bolus inspiration, breath holding, and expiratory flow rate.
D000328:Adult; D000403:Airway Resistance; D005540:Forced Expiratory Flow Rates; D006371:Helium; D006801:Humans; D008168:Lung / Q000502:physiology*; D008173:Lung Diseases, Obstructive / Q000175:diagnosis; D008176:Lung Volume Measurements / Q000379:methods*; D008448:Maximal Expiratory Flow Rate; D011868:Radioisotopes; D012115:Residual Volume; D013147:Spirometry; D014109:Total Lung Capacity
D011868:Radioisotopes; D006371:Helium