Preliminary work of a smart needling project

Precise needle placement is vital for the success of a wide variety of percutaneous surgical procedures. Insertions into soft tissues can be difficult to learn and to perform, due to tissue deformation, needle deflection and limited visual feedback. Little quantitative information is known about the interaction between needles and soft tissues during puncture. We are carrying out a "smart needling" project in which a fairly long, but slender biopsy needle will be controlled to hit the target that is inside human body, automatically and precisely. This paper reports the preliminary work which is to prove that translational oscillation of the needle can reduce target movement, and at the same time to find the optimal settings of the important factors that will produce the least target movement. The experiment platform comprises of an oscillatory needle restricted to translate horizontally. A position-trackable catheter was embedded in the phantom to act as the target. Two-Level factorial design was adopted and an exploratory data analysis (EDA) approach was used for analysis. The final results showed that oscillation at high frequency band from 2kHz to 20kHz can reduce target movement. Translation speed, oscillation frequency and amplitude are all important factors. But phantoms with different elasticities may have different best settings of these factors. For example, for soft phantoms, lower frequency, higher speed and smaller amplitude are desired for minimal target movement. Optimization searching engine will be designed correspondingly to control the needle in optimal working conditions that can produce minimal target movement.© (2005) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.