Computerized Lung Sound Analysis (CLSA)

This clinical trial is conducted within the research project 'Computerized Lung Sound Analysis'. The research goal is the development of a system enabling the automatic classification of lung sounds, which will result in a decision support system for physicians. The objective of this trial is to create a small lung sound corpus, enabling the development of a prototype of the described system. Therefore, investigators record lung sounds with several lung sound transducers distributed on the posterior chest of human test subjects.

In this clinical trial investigators record lung sounds over the posterior chest of human test subjects. The subjects are either lung-healthy (control group) or subjects with pneumothorax condition or pulmonary fibrosis. The lung sounds are recorded in supine position on an examination table. A foam pad with several lung sound transducers is placed under the back of the subjects. During the recording the subjects wear a nose clip and hold a pneumotachograph with both hands. The subjects are instructed to breath at a certain airflow rate during inspiration, with natural breathing during expiration. For each subject investigators simultaneously record 30 seconds of the airflow signal and the lung sounds from 16 lung sound transducers.

Subjects with no diagnosed lung disease. The intervention is the recording of lung sounds with the Lung Sound Recording System.

Subjects with pneumothorax. The intervention is the recording of lung sounds with the Lung Sound Recording System.

Subjects with pulmonary fibrosis. The intervention is the recording of lung sounds with the Lung Sound Recording System.

The lung sounds are recorded over the posterior chest in supine position on an examination table. A foam pad with several lung sound transducers is placed under the back of the subjects. During the recording the subjects wear a nose clip and hold a pneumotachograph with both hands. The subjects are instructed to breath at a certain airflow rate during inspiration, with natural breathing during expiration. Therefore, they receive a real-time feedback for the airflow rate. The airflow signal and the lung sounds from 16 lung sound transducers are recorded simultaneously for 30 seconds.

The lung sounds and the airflow signal are simultaneously recorded with the Lung Sound Recording System. One time frame contains several breathing phases. Depending on the lung disease normal lung sounds are either altered or adventitious lung sounds are superimposed.

Inclusion Criteria: General: Smoker and non-smoker 'Lung-healthy' subjects (control group), subjects with pneumothorax or subjects with pulmonary fibrosis Additional for 'lung-healthy' subjects: COPD < 3 (GOLD Criteria) Exclusion Criteria: General: Body Mass Index > 30 Preceding thoracic surgery Non-cooperation of the subject Intubated or tracheostomized subjects Additional for 'lung-healthy' subjects: Disease of the respiratory system Taking medication influencing the respiration