Two experiments were performed to determine the effects of friction and needle geometry during robotic needle insertion into soft tissues. In Experiment I, friction forces along the instrument axis were characterized during needle insertion into bovine liver under CT fluoroscopic imaging. Because the relative velocity of the tissue and needle affect viscous and Coulomb friction, the needle inse...

How to improve placement accuracy of needle insertion into liver tissue is of paramount interest to physicians. A robot-assisted system was developed to experimentally demonstrate its advantages in needle insertion surgeries. Experiments of needle insertion into porcine liver tissue were performed with conic tip needle (diameter 8 mm) and bevel tip needle (diameter 1.5 mm) in this study. Manual...

normal 0 false false false en-us x-none ar-sa background: robotic needle insertion in biological tissues has been known as one the most applicable procedures in sampling, robotic injection and different medical therapies and operations. objective: in this paper, we would like to investigate the effects of angular velocity in soft tissue insertion procedure by considering force-displacement diag...

PURPOSE In prostate brachytherapy, a grid is used to guide a needle tip toward a preplanned location within the tissue. During insertion, the needle deflects en route resulting in target misplacement. In this paper, 18-gauge needle insertion experiments into phantom were performed to test effects of three parameters, which include the clearance between the grid hole and needle, the thickness of...

BACKGROUND AND AIM: The aim of the present study was to evaluate the effect of different needle-insertion depths on the accuracy of the Root ZX II and Root ZX mini apex locators in the presence of various irrigants. METHODS: Ninety extracted single-canal human teeth were used in nine experimental groups. The coronal one-third of the canals was preflared, and the length to the major foramen was ...

Needle insertion can be performed with the aid of an ultrasound (US) image. Detecting the position of a needle in a US image requires considerable technical expertise. To detect whether the needle has reached the target, the physician usually relies on physically sensing the amount of force being fed back from the tip of the needle to their fingertip. The goal of our research was to develop a f...

A thorough understanding of needle-tissue interaction mechanics is necessary to optimize needle design, achieve robotically needle steering, and establish surgical simulation system. It is obvious that the interaction is influenced by numerous variable parameters, which are divided into three categories: needle geometries, insertion methods, and tissue characteristics. A series of experiments a...

PURPOSE To introduce and determine the biopsy length performance of the novel enhanced cutting edge (ECE) needle tip design, which contains high inclination angles that allow for more efficient tissue cutting. METHODS ECE and regular two-plane symmetric needle tip's biopsy performance and cutting force are compared over a series of needle insertion experiments into bovine liver under varying ...

A novel interactive virtual needle insertion simulation is presented. Simulation models are based upon planar tissue deformations and forces measured during needle insertion experiments. Users are able to control a three-degree-of-freedom virtual needle as it penetrates a linear elastostatic tissue model, while experiencing steering torques and lateral needle forces through a planar haptic inte...