Patent ID: 8403861

Claim:
A method of preselecting a test subject for determination of the presence of a space-occupying respiratory system lesion, said method comprising: determining a humidity profile of exhaled air of said test subject by measuring change of water vapour content after the start of exhalation of said test subject; comparing, using a processor, a water vapour content of the test subject at a time point after the start of exhalation with a control water vapour content in an exhalation of a person who does not have a respiratory system lesion measured at the same time point after the start of exhalation; and determining, using said processor, whether said humidity profile of exhaled air of said test subject exhibits an irregularity indicative of such a lesion based on said comparison, wherein said irregularity equates to a lower water vapour content in exhaled air of said test subject as compared to the control water vapour content at the same time point after the start of exhalation.