title: Design of an Optically Controlled MR-Compatible Active Needle.
abstract: An active needle is proposed for the development of magnetic resonance imaging (MRI)-guided percutaneous procedures. The needle uses a low-transition-temperature shape memory alloy (LT SMA) wire actuator to produce bending in the distal section of the needle. Actuation is achieved with internal optical heating using laser light transported via optical fibers and side coupled to the LT SMA. A prototype, with a size equivalent to a standard 16-gauge biopsy needle, exhibits significant bending, with a tip deflection of more than 14° in air and 5° in hard tissue. A single-ended optical sensor with a gold-coated tip is developed to measure the curvature independently of temperature. The experimental results in tissue phantoms show that human tissue causes fast heat dissipation from the wire actuator; however, the active needle can compensate for typical targeting errors during prostate biopsy.
authors.affiliation: Stanford University, Stanford, CA 94305 USA.
authors.forename: Seok Chang
authors.initials: SC
authors.lastname: Ryu
authors.affiliation: Stanford University, Stanford, CA 94305 USA.
authors.forename: Zhan Fan
authors.initials: ZF
authors.lastname: Quek
authors.affiliation: Biorobotics Laboratory, School of Mechanical and Aerospace Engineering, Seoul National University, Seoul 151-742,Korea.
authors.forename: Je-Sung
authors.initials: JS
authors.lastname: Koh
authors.affiliation: ICube Strasbourg University, CNRS, INSA, 67084 Strasbourg France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Renaud
authors.affiliation: Intelligent Fiber Optic Systems Corporation, Santa Clara, CA 95054 USA.
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Black
authors.affiliation: Intelligent Fiber Optic Systems Corporation, Santa Clara, CA 95054 USA.
authors.forename: Behzad
authors.initials: B
authors.lastname: Moslehi
authors.affiliation: Department of Radiology, Stanford University, Stanford, CA 94305 USA.
authors.forename: Bruce L
authors.initials: BL
authors.lastname: Daniel
authors.affiliation: Biorobotics Laboratory, School of Mechanical and Aerospace Engineering/IAMD, Seoul National University, Seoul 151-742, Korea.
authors.forename: Kyu-Jin
authors.initials: KJ
authors.lastname: Cho
authors.affiliation: Stanford University, Stanford, CA 94305 USA.
authors.forename: Mark R
authors.initials: MR
authors.lastname: Cutkosky
keywords: Active needle; mechanism design; medical robots and systems; optical actuation and sensing