title: Thermochromic Phantom and Measurement Protocol for Qualitative Analysis of Ultrasound Physiotherapy Systems.
abstract: Thermochromic test bodies are promising tools for qualitatively evaluating the acoustic output of ultrasound physiotherapy systems. Here, a novel phantom, made of silicone mixed with thermochromic powder material, was developed. Additionally, a procedure was developed to evaluate the stability and homogeneity of the phantom in a metrologic and statistical base. Twelve phantoms were divided into three groups. Each group was insonated by a different transducer. An effective intensity of 1.0 W/cm(2) was applied to each phantom; two operators performed the procedure three times in all phantoms. The heated area was measured after image processing. No statistical difference was observed in the heated areas for different samples or in the results for different operators. The heated areas obtained using each transducer were statistically different, indicating that the thermochromic phantom samples had sufficient sensitivity to represent the heated areas of different ultrasonic transducers. Combined with the evaluation procedure, the phantom provides an approach not previously described in the literature. The proposed approach can be used to quickly assess changes in ultrasonic beam cross-sectional shape during the lifetime of ultrasound physiotherapy systems.
authors.affiliation: Biomedical Engineering Program, COPPE, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Rejane M
authors.initials: RM
authors.lastname: Costa
authors.affiliation: Laboratory of Ultrasound/National Institute of Metrology, Quality, and Technology (Inmetro), Duque de Caxias, Rio de Janeiro, Brazil. Electronic address: avalvarenga@inmetro.gov.br.
authors.forename: André V
authors.initials: AV
authors.lastname: Alvarenga
authors.affiliation: Laboratory of Ultrasound/National Institute of Metrology, Quality, and Technology (Inmetro), Duque de Caxias, Rio de Janeiro, Brazil.
authors.forename: Rodrigo P B
authors.initials: RP
authors.lastname: Costa-Felix
authors.affiliation: Biomedical Engineering Program, COPPE, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Thaís P
authors.initials: TP
authors.lastname: Omena
authors.affiliation: Biomedical Engineering Program, COPPE, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Marco A
authors.initials: MA
authors.lastname: von Krüger
authors.affiliation: Biomedical Engineering Program, COPPE, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Wagner C A
authors.initials: WC
authors.lastname: Pereira
mesh_terms: D000162:Acoustics; D006358:Hot Temperature; D007091:Image Processing, Computer-Assisted; D019047:Phantoms, Imaging; D026741:Physical Therapy Modalities / Q000295:instrumentation*; D012828:Silicones; D014159:Transducers; D014464:Ultrasonic Therapy / Q000295:instrumentation*
chemical_list: D012828:Silicones
keywords: Metrology; Physiotherapy; Thermochromic phantom; Ultrasound