Is Saline Sealing of Needle Tract Effective to Prevent Pneumothorax after Computed Tomography-guided Lung Biopsy?

Purpose: To evaluate the efficacy of needle tract sealing using normal saline instillation for decreasing the risk of pneumothorax after computed tomography-guided lung biopsy. Material and Methods: This retrospective, single-institution study included 391 computed tomography-guided lung biopsies performed by 12 operators between January 2022 and October 2024. After exclusion, 298 biopsies were analyzed by comparing the saline seal (n = 138) and control (n = 160) groups. A 17/18-gauge or 19/20-gauge coaxial biopsy system was used, and tract sealing was performed by instilling 1-5 mL of normal saline during the withdrawal of the introducer needle in the saline seal group; tract sealing was not performed in the control group. After 1:1 propensity score matching was performed to balance baseline characteristics, the incidences of pneumothorax and chest tube placement were compared between the two groups using Fisher's exact test. Results: After propensity score matching, 108 pairs (mean lesion size: 17 mm) were well balanced. The incidence of pneumothorax did not differ significantly between the control and saline seal groups (50.0% vs. 60.2%, respectively; p = 0.171). Similarly, the incidence of chest tube placement was not significantly different between the two groups (7.4% vs. 13.0%, respectively; p = 0.260). Conclusions: According to the propensity score-matched analysis, normal saline instillation for tract sealing did not significantly reduce the incidence of pneumothorax or chest tube placement. In our cohort, which had a high prevalence of small lesions, saline sealing alone may be insufficient to reduce post-biopsy pneumothorax risk. Hence, combined strategies require further investigation.