Enhancing safety in CT-guided lung biopsies: correlation of MinIP imaging with pneumothorax risk prediction.

Objectives: This study aimed to evaluate whether minimum-intensity projection (MinIP) images could predict complications in CT-guided lung biopsies.

Methods: We retrospectively analyzed 72 procedures from January 2019 to December 2023, categorizing patients by pneumothorax and the severity of hemorrhage (grade 2 or higher). Radiodensity measurements were performed using lung window (LW) and MinIP (10-mm slab) images. Regions of interest (ROIs) were placed at sites of the lowest density along the biopsy pathway. Absolute values were recorded, categorized by a radiodensity level of -850 HU, and assessed using our bridged radiological observations with measurement-optimized model (BROM-OLB) model with validation from three additional ROIs. Emphysema was visually scored. Statistical analysis included univariate analysis (Fisher's exact and Mann-Whitney U-tests) and binomial logistic regression to identify confounders.

Results: Lower radiodensity values in MinIP images in the access route, particularly with the BROM-OLB MinIP method, were significantly associated with a higher risk of pneumothorax (5/39, 13% vs 27/33, 82%, p < 0.01; Sensitivity 81.8% and Specificity 87.2%). Pneumothorax was more common with longer procedures (p < 0.05). Lower LW density values correlated with higher pulmonary hemorrhage rates (p < 0.01). Binomial logistic regression identified positive BROM-OLB MinIP results (OR 28.244, 95% CI: 7.675-103.9, p < 0.01) and lower LW density (OR 0.992, 95% CI: 0.985-0.999, p = 0.025) as independent risk factors. The optimal threshold values to predict pneumothorax were -868 HU in MinIP images and -769 HU in LW.

Conclusion: The assessment of MinIP images is superior, and in combination with relative quantitative measurement of radiodensity for access route planning, it can reduce the risk of pneumothorax in CT-guided lung biopsies.

Critical relevance statement: This article critically evaluates the risk factors for complications in CT-guided lung biopsies, highlighting the potential of MinIP images for predicting pneumothorax risk, thereby advancing clinical radiology practices to improve patient safety and reduce healthcare costs.

Key points: This work investigates if MinIP images efficiently predict CT-guided lung biopsy complications. MinIP imaging identified higher pneumothorax risk post-CT lung biopsy with superior accuracy. Our method detects high-risk lung changes linked to pneumothorax without additional software.