Pneumothorax Rate and Diagnostic Adequacy of Computed Tomography–guided Lung Nodule Biopsies Performed With 18 G Versus 20 G Needles: A Cross-Sectional Study

PURPOSE: Conflicting data exist with regard to the effect of needle gauge on outcomes of computed tomography (CT)-guided lung nodule biopsies. The purpose of this study was to compare the complication and diagnostic adequacy rates between 2 needle sizes: 18 G and 20 G in CT-guided lung nodule biopsies. MATERIALS AND METHODS: This retrospective cohort study examined CT-guided lung biopsies performed between March 2014 and August 2016 with a total of 550 patients between the ages of 30 and 94. Biopsies were performed using an 18-G or a 20-G needle. Procedure-associated pneumothorax and other complication rates were compared between the 2 groups. Univariate and multiple logistic regression analyses were performed. RESULTS: There was no significant difference in pneumothorax rate between 18 G (n=125) versus 20 G (n=425) (rates: 25.6% vs. 28.7%; P=0.50; odds ratio [OR]=0.86; 95% confidence interval [CI]=0.54-1.35), chest tube insertion rate (4.8% vs. 5.6%; P=0.71; OR=0.84; 95% CI=0.34-2.11), or diagnostic adequacy (95% vs. 93%; P=0.36; OR=1.51; 95% CI=0.61-3.72). Multiple logistic regression analysis demonstrated emphysema along the biopsy path (OR=3.12; 95% CI=1.63-5.98) and nodule distance from the pleural surface >/=4 cm (OR=1.85; 95% CI=1.05-3.28) to be independent risk factors for pneumothorax. CONCLUSION: No statistically significant difference in pneumothorax rate or diagnostic adequacy was found between 18-G versus 20-G core biopsy needles. Independent risk factors for pneumothorax include emphysema along the biopsy path and nodule distance from the pleural surface.