A New Method of Visualizing Lung Ventilation by Means of Breathing Sounds

Oskar Seifert, Volker Gross, Henning Schneider, Martin Kramer, Andreas Weissflog, Keywan Sohrabi

Standard imaging procedures to determine lung ventilation are CAT-scan and magnetic resonance imaging. These procedures involve high radiation exposure, high expenditure and plenty of time. They are not suitable for preventive and multi-examinations, neither for monitoring. The new ThoraView®-system dynamically displays lung ventilation based on lung sound detection and analysis. The aim of this study was to validate (i) the display of lung ventilation (ii) and if ThoraView® can detect and display nonventilated areas. In a clinical study, 17 healthy piglets were examined. Nonventilated lung areas were created using a bronchial blocker. CAT-Scan and magnetic resonance imaging were used to verify the regional distribution of (non)ventilation. The ThoraView®-system used 30+1 microphones on a dorsally positioned microphone pad to record and analyze breathing sounds. Greyscale pixel values of ThoraView® images from both ventilated and nonventilated lung sides were compared. High values indicate high ventilation, whereas low values stand for less ventilation. The new system was able to successfully detect and display lung ventilation and also nonventilated areas. Mean grey pixel values were 346.47 ± 8.42 and 404.27 ± 4.92 for the blocked and nonblocked lung sides, respectively. Significance was p ≤ 0.01. We conclude that ThoraView® has the potential to substantially support clinical routine as an innovative and comfortable monitoring device for the increasing numbers of respiratory diseases. Further studies are necessary to validate the operational capability in human medicine.