Biopsies of pulmonary lesions are essential for increasing the accuracy of diagnosis and treatment for respiratory illnesses such as lung cancer. Currently, manual biopsies are performed via bronchoscopy. Because bronchi tend to branch thinner and more complicatedly as they go to the periphery, it’s a challenge to choose one and fine-tune the propelling movement. Difficulty in reaching the lesion with biopsy forceps can mean inadequate diagnosis accuracy.

The development of instruments and mechanisms that can reliably reach the target in the lungs is required for adequately testing with an endoscope, but the looming challenge has been finding a mechanism to advance the biopsy forceps reliably to the target inside the ultrafine and widely branching bronchi. Professor Yuichiro Takai of the Department of Respiratory Medicine, Omori Medical Center, Toho University, and Professor Hideyuki Tsukagoshi of the Department of System and Control Engineering, Tokyo Tech, are developing a new self-propelled catheter designed to generate traveling waves in multiple chambers by adding and reducing pressure inside one tube. This allows for moving forward with peristaltic motion within an ultrafine structure such as a bronchus.

The catheter also has an actively curving function for choosing the direction of propulsion, as well as a flexing drive function for adjusting to changes in line diameter.

The goal is to increase the accuracy of branches that can be propelled, include a camera to collect information on the inside of the bronchi, develop functions applicable to biopsies and treatment, and put instruments to practical use.