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CT-guided lung biopsies have become an invaluable tool in the field of interventional radiology, allowing for accurate diagnosis and treatment planning in patients with pulmonary nodules and suspicious lung lesions. While biopsies have traditionally been used for diagnosis, lung biopsies are increasingly being requested in order to gain insight into a patient’s biomarkers as well.
However, as with any medical procedure, complications can occur, and it is crucial for radiologists and medical professionals to be aware of these risks and take steps to minimize them. In this article, we’ll explore four potential complications associated with CT-guided lung biopsies and provide essential tips on how to avoid them.
1. Pneumothorax
Pneumothorax is the most common complication of CT-guided lung biopsies, with a reported rate of 17-26.6% (1-3). It occurs when air accumulates in the pleural space, resulting in lung collapse. Because of the complexity of lung biopsies, higher rates of pneumothorax can be observed in procedures performed by less experienced radiologists, with a 17% rate for experienced radiologists compared with 30% for all other operators (4). Longer needle paths have also been associated with risk of pneumothorax (1). Patient factors affecting risk of pneumothorax include lesion size and depth, as well as the presence of emphysema or chronic obstructive pulmonary disease (COPD) (4, 5).
Careful planning is required to ensure accurate needle placement during the procedure, traversing the least amount of aerated lung, avoiding bullae and pneumatoceles whenever feasible and keeping readjustments to a minimum. Here, CT navigation systems can be of great help by allowing for planning and execution of optimal access routes to avoid pneumothorax, even out of plane routes. By supporting accurate needle placement, fewer corrections may be necessary, further reducing risk. Additional guidance could also minimize the difference in outcomes across experience levels of radiologists.
Some studies have also found that a rapid needle-out, patient-rollover (within 10 seconds) maneuver reduces the rate of pneumothorax complications (6,7). Other techniques include sealing the needle track with hydrogel, a blood patch or saline solution (8,9). More research is needed to definitively demonstrate their effectiveness, but they are promising techniques.
2. Pulmonary Hemorrhage
While rarely life threatening, pulmonary hemorrhage during lung biopsies has a reported rate of between 4-27% (3), and it is therefore essential to take precautions to avoid excessive bleeding. Higher bleeding rates are associated with smaller lesions (perhaps due to the increased precision needed to reach them), longer needle paths, absence of pleural effusion, and multiple pleural punctures.
It is recommended to perform a thorough review of the patient's coagulation profile before the procedure, especially in patients on anticoagulant or antiplatelet medications, where percutaneous procedures are contraindicated. Additionally, ensuring adequate needle size selection and avoiding vessels adjacent to the target lesion can minimize the risk of hemorrhage. If possible, the trajectory of the needle should aim away from the aorta and the heart, to avoid damaging those structures.
3. Air Embolism
Although extremely rare, air embolism is a life-threatening complication that can occur during lung biopsies. It occurs when air enters the bloodstream through damaged lung tissue or a pulmonary vessel. This happens when the needle crosses or enters into a pulmonary vein and the negative pressure gradient from inspiration sucks air into the biopsy needle. It can cause arrhythmias, hypoxia, cardiovascular collapse or stroke.
To prevent air embolism, it is essential to properly secure the needle during insertion and ensure that it remains within the target lesion. Some doctors recommend occluding the biopsy needle with an inner stylet, saline drops or a finger (9). Monitoring patients closely during and after the procedure for symptoms of air embolism, such as chest pain, dyspnea, or altered mental status, is crucial for early detection and prompt intervention.
4. Tumor Seeding
Tumor seeding refers to the inadvertent spread of cancer cells along the needle tract or into adjacent tissues during the biopsy procedure (3). While tumor seeding is a rare complication, it is crucial for radiologists and medical professionals to be aware of best practices to minimize this risk.
Prior to performing a lung biopsy, the patient’s clinical history, imaging findings, and suspicion of malignancy should be carefully evaluated. The lesion's size, location, and proximity to critical structures should be considered.
To minimize the risk of tumor seeding, it is recommended to use a single needle pass technique whenever feasible (8). This approach involves accurately positioning the needle within the target lesion and obtaining an adequate tissue sample in a single pass. Multiple needle passes increase the risk of needle tract involvement and potential tumor seeding. CT navigation systems, such as the Cube Navigation System, can aid in precise needle placement and reduce the number of needle passes.
Conclusion
CT-guided lung biopsies are essential procedures in interventional radiology, providing accurate diagnoses and guiding treatment decisions for patients with suspicious lung lesions. By being aware of potential complications and implementing proven preventive strategies, radiologists and medical professionals can minimize risks and ensure the safe and effective performance of these procedures. Utilizing navigation systems in CT-guided lung biopsies can allow use of optimal access routes, reduce the number of needle adjustments, and improve overall patient outcomes.
References
1. Khan MF, Straub R, Moghaddam SR, et al. Variables affecting the risk of pneumothorax and intrapulmonal hemorrhage in CT guided transthoracic biopsy. Eur Radiol 2008;18(7):1356–1363
2. Saji H, Nakamura H, Tsuchida T, et al. The incidence and the risk of pneumothorax and chest tube placement after percutaneous CT guided lung biopsy: the angle of the needle trajectory is a novel predictor. Chest 2002;121(5):1521–1526
3. Wu CC, Maher MM, Shepard J-AO. Complications of CT-guided percutaneous needle biopsy of the chest: prevention and management. AJR Am J Roentgenol 2011;196(6):W678-82
4. Yeow K-M, Su I-H, Pan K-T, et al. Risk factors of pneumothorax and bleeding: multivariate analysis of 660 CT-guided coaxial cutting. JVasc Interv Radiol 2003;14(5):581–588
5. Boskovic T, Stanic J, Pena-Karan S, et al. Pneumothorax after transthoracic needle biopsy of lung lesions under CT guidance. J Thorac Dis. 2014;6 Suppl 1(Suppl 1):S99-S107. doi:10.3978/j.issn.2072-1439.2013.12.08
6. O’Neill AC, McCarthy C, Ridge CA, Mitchell P, Hanrahan E, Butler M, et al. Rapid needle-out patient-rollover time after percutaneous CT-guided transthoracic biopsy of lung nodules: effect on pneumothorax rate. Radiology 2012;262:314-9.
7. Kim JI, Park CM, Lee SM, Goo JM. Rapid needle-out patient rollover approach after cone beam CT-guided lung biopsy: effect on pneumothorax rate in 1,191 consecutive patients. Eur Radiol 2015;25:1845-53.
8. Beck, C. & Suh R. Minimizing Complications for Lung Biopsy. Backtable Radiology Podcast, 3. Jan 2023, retrieved from: https://www.backtable.com/shows/vi/podcasts/278/minimizing-complications-for-lung-biopsies
9. Winokur, R.S., Pua,B., Sullivan, B., & Madoff, D.C. Percutaneous Lung Biopsy: Technique, Efficacy, and Complications. Semin Intervent Radiol 2013;30:121–127