Bronchoscopic Evaluation of a Steerable Needle for Simulated Tumor Targets in the Lung Periphery: A Feasibility Study (Bullseye)

Abstract

Background: Peripheral bronchoscopy is often performed to biopsy peripheral pulmonary lesions. Despite technological advancements to improve reach and access to the lung periphery, the diagnostic yield of peripheral bronchoscopy has been inconsistent, and challenging, particularly for lesions that are adjacent to peripheral bronchi. Current biopsy instruments are reliant on the catheter or scope to align properly with targeted lesions. Objectives: This study evaluates the feasibility of using a steerable biopsy needle to gain access to peripheral tumor targets in a cadaveric model. Methods: Simulated tumor targets 10–30 mm in axial diameter were placed into human cadavers. Bronchoscopy was performed using a 4.2 mm OD flexible bronchoscope, CT-anatomic correlation, and multi-planar fluoroscopy for lesion localization. Once at the targeted location, a steerable needle was deployed and the needle position was determined to be in the central zone, peripheral zone, or outside of the lesion by cone beam CT imaging. If the needle position was within the lesion, a fiducial marker was deployed to mark the needle position, and the needle was articulated and/or rotated in an attempt to place another fiducial marker into a different location within the same lesion. If the needle was outside of the lesion, the bronchoscopist was provided with two additional attempts to gain access to the lesion. Results: Fifteen tumor targets were placed with a mean lesion size of 20.4 mm. The majority of lesions were located in the upper lobes. One fiducial marker was placed in 93.3% of lesions and a second fiducial marker was successfully placed in 80% of lesions. A fiducial marker was placed within the central zone in 60% of lesions. Conclusion: The steerable needle was successfully placed within 93% of targeted lesions 10–30 mm in diameter in a cadaveric model, with the ability steer the instrument into another portion of the lesion in 80% of cases. The ability to steer and control needle positioning toward and within peripheral lesions may complement existing catheter and scope technology during peripheral diagnostic procedures.