Safe Zone to Avoid Pneumothorax in a CT-Guided Lung Biopsy.

Pneumothorax is one of the most frequent complications of computed tomography (CT)-guided lung biopsies. We aim to identify the safe zone of the needle-pleura angle during a CT-guided lung biopsy. Fifty-two patients underwent CT-guided lung biopsies between January 2020 and September 2022 (27 males, 25 females, median age 70 years). Right and left needle angles were measured and correlated to the incidence of pneumothorax. The minimum delta (δmin) was calculated as the absolute value of the difference between a 90° angle and the right and left angles. t-test p-values for δmin were conducted. We recorded 29 patients with pneumothorax, including intraprocedural and transient, postprocedural with minimal symptoms, or postprocedural requiring a chest tube insertion. Thirty-two patients had a δmin ≥ 10°, while 20 had a δmin < 10°. Of the patients with a δmin < 10°, 30% experienced pneumothorax compared to 71.8% in patients with δmin ≥ 10° (p = 0.0023). The study results show that as the needle's angle deviates from the perpendicular, with an absolute value of more than 10°, the likelihood of pneumothorax increases significantly. A needle-pleura angle between 80° and 100° gives the operator a safe zone to reduce the risk of pneumothorax.

Associations between Covariates and Pneumothorax Observations in CT-Guided Lung Biopsies.

The purpose of this study is to assess the effect of nine covariates on the occurrence or absence of stable or symptomatic pneumothorax. Forty-three patients underwent CT-guided lung biopsies from January 2020 to January 2022 (24 m, 19 f, median age 70 years). All the interventions were carried out with a semi-automatic 18G needle and a 17G trocar in a prone or supine position. Different covariates were measured and correlated to the rate and severity of the pneumothoraces observed. Nominal two-sided t-test p-values for the continuous variables and Fisher's exact test results for the categorical variables were conducted. The data included the lesion size, distance to the pleura, needle-pleura angle, age, gender, position during the procedure, and the presence of chronic obstructive pulmonary disease. Patients with an observed pneumothorax had an average angle between the needle and the pleura of 74.00° compared to 94.68° in patients with no pneumothorax (p-value = 0.028). A smaller angle measurement correlated with a higher risk of pneumothorax development. The needle-pleural angle plays a vital role in the outcome of a CT-guided lung biopsy. Correctly adjusting the needle-pleural angle can diminish the pneumothorax risk associated with a CT-guided lung biopsy. The study results show that as the needle's angle deviates from the perpendicular, the pleural surface area experiencing trauma increases, and pneumothorax is more likely to occur.