title: The Feasibility of Thermal Imaging as a Future Portal Imaging Device for Therapeutic Ultrasound.
abstract: This technical note describes a prototype thermally based portal imaging device that allows mapping of energy deposition on the surface of a tissue mimicking material in a focused ultrasound surgery (FUS) beam by using an infrared camera to measure the temperature change on that surface. The aim of the work is to explore the feasibility of designing and building a system suitable for rapid quality assurance (QA) for use with both ultrasound- and magnetic resonance (MR) imaging-guided clinical therapy ultrasound systems. The prototype was tested using an MR-guided Sonalleve FUS system (with the treatment couch outside the magnet bore). The system's effective thermal noise was 0.02°C, and temperature changes as low as 0.1°C were easily quantifiable. The advantages and drawbacks of thermal imaging for QA are presented through analysis of the results of an experimental session.
authors.affiliation: Acoustics and Ionizing Radiation Division, National Physical Laboratory, Hampton Road, Teddington, UK. Electronic address: piero.miloro@npl.co.uk.
authors.forename: Piero
authors.initials: P
authors.lastname: Miloro
authors.affiliation: Therapeutic Ultrasound, Division of Radiotherapy and Imaging, Joint Department of Physics, Institute of Cancer Research: Royal Marsden NHSF Trust, Sutton, Surrey, UK.
authors.forename: John
authors.initials: J
authors.lastname: Civale
authors.affiliation: Therapeutic Ultrasound, Division of Radiotherapy and Imaging, Joint Department of Physics, Institute of Cancer Research: Royal Marsden NHSF Trust, Sutton, Surrey, UK.
authors.forename: Ian
authors.initials: I
authors.lastname: Rivens
authors.affiliation: Acoustics and Ionizing Radiation Division, National Physical Laboratory, Hampton Road, Teddington, UK.
authors.forename: Adam
authors.initials: A
authors.lastname: Shaw
mesh_terms: D004867:Equipment Design; D005240:Feasibility Studies; D053783:Magnetic Resonance Imaging, Interventional / Q000379:methods*; D014464:Ultrasonic Therapy / Q000379:methods*
keywords: Acoustic field evaluation; High intensity focused ultrasound dosimetry; Infrared camera; Magnetic resonance–guided focused ultrasound surgery; Quality assurance; Thermal mapping