On using steerable needles for the 3D printing of biomaterials

Abstract

Steerable needles are often used in surgical operations (such as percutaneous intervention) as a relatively non-invasive approach in the treatment of certain diseases (e.g., cancer, etc.). The key advantage of this being that the needle tip can work its way through a body, avoiding all sensitive areas and / or obstacles, and ultimately reach an otherwise unreachable area (causing minimal damage). This work describes an approach to 3D printing utilizing steerable needles and defines a methodology through which biomaterial can be deposited and polymerized in place within a penetrable body to create a fibre of certain characteristics and / or behaviour. Using gelatine as the phantom body in which we 3D print with steerable needles, it is possible using a novel steerable needle experimental machine to deposit sodium alginate of a certain length in a particular orientation at certain points within the phantom and subsequently add calcium chloride to initiate polymerization into a calcium alginate fibre of certain properties. This article presents the engineering and software requirements to control a steerable needle with specific definition for 3D printing, the phantom within which we 3D print is defined, and finally calcium alginate fibers are offered, that are polymerized within the gelatine phantom. This work attempts to take a step towards the development of electro-mechanical devices which could in future allow for the 3D printing of fibers or other specific structures within the human body as part of the biomedical field.