A novel medical tool engineered at Tokyo Institute of Technology and Toho University, Japan, could help doctors reach areas of the lung that can be tricky to access using conventional bronchoscopes.

During biopsies of pulmonary lesions, clinicians must navigate airways that become progressively smaller and Delivery experiment within bronchus model and a self-propelled catheter prototype. Source: Hideyuki Tsukagoshimore complicated as they branch deep in the lungs. This makes it difficult to reliably reach the lesion with the biopsy forceps, resulting in inadequate diagnosis accuracy.

The researchers devised a self-propelled catheter for this application. Earthworm-like motion is effected as the catheter propagates waves along its tubular form in response to pressure changes. This peristaltic propulsion allows the catheter to travel along very narrow airways such as a bronchus. The device has an actively curving function for choosing the direction of propulsion, and a flexing drive function for adjusting to changes in line diameter.

Promising results were obtained when the catheter was tested in a model of the lungs. The researchers plan to include a camera to collect information on the inside of the bronchi, develop functions applicable to biopsies and treatment, and put the tool to practical use.