Background/objectives: This study aimed to investigate pneumothorax risk, focusing on the gravitational effect of pleural pressure caused by specific patient positioning.
Methods: We retrospectively analyzed 144 percutaneous CT-guided lung biopsies performed between January 2019 and December 2023. Patients were grouped into those with or without pneumothorax. Variations in patient positioning (prone, supine, lateral, lesion in decubitus biopsy-side-down [LD BSD] and the dependent area [L DA M], and access route beginning in the dependent area [AR LD M]) were compared using the chi-square, Fisher's exact, and Mann-Whitney U tests. Performance metrics were evaluated. Univariate and binomial logistic regression models assessed the influence of these factors and other patient-related and interventional parameters on pneumothorax occurrence.
Results: Three positional variants (AR DA M, L DA M, and L LD BSD; p < 0.001), general emphysema (p = 0.009), emphysema in the access route (p = 0.025), greater needle size (18G vs. 20G; p < 0.001), and the use of a side-cut instead of a full-core system (p = 0.002) were significantly linked to lower peri-interventional pneumothorax incidence. Even after adjusting for various factors, AR DA M and general emphysema remained independently associated with a reduced pneumothorax risk (OR 0.168, p < 0.001; OR 2.72, p = 0.034). Assessing the dependent zones showed superior performance regardless of the patient's position, with the best performance demonstrated for AR DA M (AUC 0.705; sensitivity 60%, specificity 81.8%).
Conclusions: Focusing on the dependent zones of each lung and adjusting the access route accordingly can significantly reduce the risk of pneumothorax compared to conventional positioning techniques.
Keywords: biopsy; image-guided biopsy; lung; pneumothorax; risk factors; tomography.