A left lung with four lobes: a new discovery during the thoracotomy for recurrent primary spontaneous pneumothorax

Background The right and left lung anatomy are similar but asymmetrical. The right lung consists of three lobes, and the left lung consists of two lobes. Our study is unique because of discovering a very rare morphological feature of the left lung which has not been reported yet. By the way, we compared two different available chemical agents for pleurodesis (talc and bleomycin) according to side effects, complications, and pneumothorax recurrence. Case presentation We reported a case of bilateral primary spontaneous pneumothorax, who underwent talc slurry and bleomycin pleurodesis at right and left side retrospectively, and then complicate with left-sided recurrent spontaneous pneumothorax, so underwent open thoracotomy and was surprisingly and accidentally found to have 4 lobes and 3 fissures in left lung. Conclusion In our case report, there were one main oblique fissure and two accessory fissures which divided the lung into 4 separated lobes, and this discovery in human’s and other animals’ lung anatomy has not been previously reported. In our case study, the talc slurry was more effective in preventing spontaneous pneumothorax recurrence, but with more side effects than bleomycin. We could hypothesize that the morphological variation of the lung might affect spontaneous pneumothorax development and recurrence.

Pulmonary Lobe Segmentation in CT Images Based on Lung Anatomy Knowledge

In computed tomography (CT) images, pulmonary lobe segmentation is an arduous task due to its complex structures. To remedy the problem, we introduce a new framework based on lung anatomy knowledge for lung lobe segmentation. Firstly, the priori knowledge of lung anatomy is used to identify the fissure region of interest. Then, an oriented derivative of stick filter is applied to isolate plate-like structures from clutters for lobar fissure verification. Finally, a surface fitting model is employed to complete the incomplete fissure surface for lung lobe segmentation. Compared with manually segmented fissure references, the designed approach obtained a high median F1-score of 0.8865 in the left lung and obtained a high median F1-score of 0.9200 in the right lung. The average percentages of the segmented lung lobes in the lung lobe ground truth are 0.960, 0.989, 0.973, 0.920, and 0.985 for the left upper, left lower, right upper, right middle, and right lower lobes, respectively. The perfect performance of the proposed scheme is tested by visual inspection and quantitative evaluation.

lapdMouse: associating lung anatomy with local particle deposition in mice

To facilitate computational toxicology, we developed an approach for generating high-resolution lung-anatomy and particle-deposition mouse models. Major processing steps of our method include mouse preparation, serial block-face cryomicrotome imaging, and highly automated image analysis for generating three-dimensional (3D) mesh-based models and volume-based models of lung anatomy (airways, lobes, sublobes, and near-acini structures) that are linked to local particle-deposition measurements. Analysis resulted in 34 mouse models covering 4 different mouse strains (B6C3F1: 8, BALB/C: 11, C57Bl/6: 8, and CD-1: 7) as well as both sexes (16 male and 18 female) and different particle sizes [2 μm ( n = 15), 1 μm ( n = 16), and 0.5 μm ( n = 3)]. On average, resulting mouse airway models had 1,616.9 ± 298.1 segments, a centerline length of 597.6 ± 59.8 mm, and 1,968.9 ± 296.3 outlet regions. In addition to 3D geometric lung models, matching detailed relative particle-deposition measurements are provided. All data sets are available online in the lapdMouse archive for download. The presented approach enables linking relative particle deposition to anatomical structures like airways. This will in turn improve the understanding of site-specific airflows and how they affect drug, environmental, or biological aerosol deposition. NEW & NOTEWORTHY Computer simulations of particle deposition in mouse lungs play an important role in computational toxicology. Until now, a limiting factor was the lack of high-resolution mouse lung models and measured local particle-deposition information, which are required for developing accurate modeling approaches (e.g., computational fluid dynamics). With the developed imaging and analysis approach, we address this issue and provide all of the raw and processed data in a publicly accessible repository.