A Bronchial Puncture Mechanism for Transoral Access to the Lung Parenchyma1

More people die from lung cancer each year than any other form of cancer. Over 150,000 lives are lost to the disease each year in the U.S. alone [1]. Early detection is critical in reducing the mortality rate, and despite advances in imaging, biopsy remains the only definitive diagnostic tool. The most common lung biopsy approaches are percutaneous and transoral. Percutaneous biopsy punctures the pleura (the membrane surrounding the lung) in order to reach the suspicious nodule and risks pneumothorax (lung collapse), which is a serious complication and can be deadly for patients with poor baseline lung function. Transoral lung biopsy is preferable due to the fact that the biopsy device never traverses the pleura. However, current bronchoscopes cannot access the majority of the peripheral lung, due to their large diameter in relation to bronchi diameter. While smaller diameter endoscopes and endoscopelike devices are under development, there will always remain locations where a path that exits the bronchi and travels through the parenchyma is desirable, either because it is shorter or because the nodule lies away from a usable bronchial access path. To facilitate the biopsy tool exiting the bronchi to reach such targets, we have developed the puncture mechanism described in this paper. In addition to biopsy with a straight-line biopsy needle, our device may enable the use of steerable needles in the lung parenchyma. Recent advances in robotics such as concentric tube robots (CTRs) [2] and bevel-tip steerable needles [3] (among other new needle steering technologies) may be useful in reaching targets through controllable curved paths. But these technologies require the means of exiting the bronchi that we provide in this paper. Inspired by the prior work showing that fast needle insertion can controllably transit tissue with minimal deformation [4–6], in this paper we develop a bronchoscope-deployed system that can drive the needle tip through the bronchial wall and surrounding cartilage and connective tissue, providing a port for subsequent deployment of biopsy needles and/or steerable needles into the lung parenchyma.