Dear Editor,
We thank the authors for their thoughtful comments on our study investigating the pleural tail sign (PTS) as a predictor of severe pneumothorax following computed tomography (CT)–guided lung biopsy.1
We agree that pneumothorax following CT–guided lung biopsy is a multifactorial complication dependent on established patient-related and procedural factors, including emphysema and other chronic lung diseases.2, 3 We acknowledge that an important limitation of our study is that chronic lung parenchymal changes were not systematically assessed and, therefore, could not be included in the multivariable analysis. Given their known impact, residual confounding cannot be excluded.
Regarding the definition of the primary endpoint, we acknowledge that the need for chest tube placement may be influenced by operator judgment. However, we deliberately selected this outcome because it represents a clinically meaningful endpoint reflecting complications that require active intervention.
We also appreciate the comment on interobserver variability. Although the observed agreement was moderate, the proposed two-tier classification was intentionally designed as a simplified and pragmatic approach to facilitate clinical applicability. Moreover, we believe that interobserver agreement could be improved with minimal training and a clear definition of the PTS groups.
Given the study’s retrospective design and the potential for confounding, the findings should be considered hypothesis-generating. Future studies integrating imaging and clinical variables with standardized outcome definitions are needed to better define its role in clinical practice.
We thank the authors once more for their insightful comments and for contributing to the discussion on this topic.
