title: Toward a comprehensive interpretation of intravital microscopy images in studies of lung tissue dynamics.
abstract: Intravital microscopy (IVM) is a well-established imaging technique for real-time monitoring of microscale lung tissue dynamics. Although accepted as a gold standard in respiratory research, its characteristic image features are scarcely understood, especially when trying to determine the actual position of alveolar walls. To allow correct interpretation of these images with respect to the true geometry of the lung parenchyma, we analyzed IVM data of alveoli in a mouse model in comparison with simultaneously acquired optical coherence tomography images. Several IVM characteristics, such as double ring structures or disappearing alveoli in regions of liquid filling, could be identified and related to the position of alveoli relative to each other. Utilizing a ray tracing approach based on an idealized geometry of the mouse lung parenchyma, two major reflection processes could be attributed to the IVM image formation: partial reflection and total internal reflection between adjacent alveoli. Considering the origin of the reflexes, a model was developed to determine the true position of alveolar walls within IVM images. These results allow thorough understanding of IVM data and may serve as a basis for the correction of alveolar sizes for more accurate quantitative analysis within future studies of lung tissue dynamics.
authors.affiliation: Technische Universität Dresden, Faculty of Medicine Carl Gustav Carus, Department of Anesthesiology and Intensive Care Medicine, Clinical Sensoring and Monitoring, Fetscherstraße 74, Dresden 01307, Germany.
authors.forename: Maria
authors.initials: M
authors.lastname: Gaertner
authors.affiliation: Charité - Universitätsmedizin Berlin, Labor für Biofluidmechanik, Augustenburger Platz 1, Berlin 13353, Germany.
authors.forename: Kerstin
authors.initials: K
authors.lastname: Schirrmann
authors.affiliation: Technische Universität Dresden, Faculty of Medicine Carl Gustav Carus, Department of Anesthesiology and Intensive Care Medicine, Clinical Sensoring and Monitoring, Fetscherstraße 74, Dresden 01307, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Schnabel
authors.affiliation: Technische Universität Dresden, Faculty of Medicine Carl Gustav Carus, Department of Anesthesiology and Intensive Care Medicine, Clinical Sensoring and Monitoring, Fetscherstraße 74, Dresden 01307, GermanycEVONTA-Technology GmbH, Maria-Reiche-Straße 1, Dr.
authors.forename: Sven
authors.initials: S
authors.lastname: Meissner
authors.affiliation: Charité - Universitätsmedizin Berlin, Labor für Biofluidmechanik, Augustenburger Platz 1, Berlin 13353, Germany.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Kertzscher
authors.affiliation: Technische Universität Dresden, Faculty of Medicine Carl Gustav Carus, Department of Anesthesiology and Intensive Care Medicine, Clinical Sensoring and Monitoring, Fetscherstraße 74, Dresden 01307, Germany.
authors.forename: Lars
authors.initials: L
authors.lastname: Kirsten
authors.affiliation: Technische Universität Dresden, Faculty of Medicine Carl Gustav Carus, Department of Anesthesiology and Intensive Care Medicine, Clinical Sensoring and Monitoring, Fetscherstraße 74, Dresden 01307, Germany.
authors.forename: Edmund
authors.initials: E
authors.lastname: Koch
mesh_terms: D000818:Animals; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D000069416:Intravital Microscopy / Q000379:methods*; D008168:Lung / Q000033:anatomy & histology*; D051379:Mice; D008954:Models, Biological; D011650:Pulmonary Alveoli / Q000033:anatomy & histology*; D041623:Tomography, Optical Coherence / Q000379:methods*