A novel structural risk index for primary spontaneous pneumothorax: Ankara Numune Risk Index

Radiographic chest wall abnormalities in primary spontaneous pneumothorax identified by artificial intelligence

Primary spontaneous pneumothorax (PSP) primarily affects slim and tall young males. Exploring the etiological link between chest wall structural characteristics and PSP is crucial for advancing treatment methods. In this case-control study, chest computed tomography (CT) images from patients undergoing thoracic surgery, with or without PSP, were analyzed using Artificial Intelligence. Convolutional Neural Network (CNN) model of EfficientNetB3 and InceptionV3 were used with transfer learning on the Imagenet to compare the images of both groups. A heatmap was created on the chest CT scans to enhance interoperability, and the scale-invariant feature transform (SIFT) was adopted to further compare the image level. A total of 2,312 CT images of 26 non-PSP patients and 1,122 CT images of 26 PSP patients were selected. Chest-wall apex pit (CAP) was found in 25 PSP and three non-PSP patients (p < 0.001). The CNN achieved a testing accuracy of 93.47 % in distinguishing PSP from non-PSP based on chest wall features by identifying the existence of CAP. Heatmap analysis demonstrated CNN's precision in targeting the upper chest wall, accurately identifying CAP without undue influence from similar structures, or inappropriately expanding or minimizing the test area. SIFT results indicated a 10.55 % higher mean similarity within the groups compared to between PSP and non-PSP (p < 0.001). In conclusion, distinctive radiographic chest wall configurations were observed in PSP patients, with CAP potentially serving as an etiological factor linked to PSP. This study accentuates the potential of AI-assisted analysis in refining diagnostic approaches and treatment strategies for PSP.

Correlation between Sternal Slope Angle and Primary Spontaneous Pneumothorax in Young Males, a Propensity Score Match Analysis

It is generally accepted that primary spontaneous pneumothorax (PSP) is found mostly in tall, thin young males. However, the precise etiology of PSP is unclear. We compared some thoracic structural angles of PSPs and controls in young males to determine the predominant factor. CT data of 43 male PSPs (age 21.88 ± 5.30) and 30 controls (age 21.47 ± 5.47) were collected. The angle of thoracic vertebrae slope (∠α), sternal slope angle (∠β), and tracheal-sternal stem angle (∠γ) were measured in the sagittal position. Carina angle (∠δ) was measured in the coronal position. After a propensity score match (PSM) of age and smoking history, the angles were comparatively evaluated. There were significant differences in all four angles between two unmatched groups, while only in three (∠β, ∠γ, and ∠δ) after PSM was performed. The correlation between ∠β and PSP was most significant, and R² was 0.456. The prediction accuracy of ∠β was 81.3%, OR was 1.386, 95% confidence interval was (1.095-1.754). The sternal slope angles in PSPs are greater than controls indicate the sternal slope angle is associates with the development of PSP and it could be a thoracic structural index to predict the risk of PSP occurrence. Clin. Anat. 33:605-609, 2020. © 2019 Wiley Periodicals, Inc.