title: Gel phantom for use in high-intensity focused ultrasound dosimetry.
abstract: An optically transparent phantom was developed for use in high-intensity focused ultrasound (US), or HIFU, dosimetry studies. The phantom is composed of polyacrylamide hydrogel, embedded with bovine serum albumin (BSA) that becomes optically opaque when denatured. Acoustic and optical properties of the phantom were characterized as a function of BSA concentration and temperature. The speed of sound (1544 m/s) and acoustic impedance (1.6 MRayls) were similar to the values in soft tissue. The attenuation coefficient was approximately 8 times lower than that of soft tissues (0.02 Np/cm/MHz for 9% BSA). The nonlinear (B/A) coefficient was similar to the value in water. HIFU lesions were readily seen during formation in the phantom. In US B-mode images, the HIFU lesions were observed as hyperechoic regions only if the cavitation activity was present. The phantom can be used for fast characterization and calibration of US-image guided HIFU devices before animal or clinical studies.
authors.affiliation: Inserm, Lyon, France.
authors.forename: Cyril
authors.initials: C
authors.lastname: Lafon
authors.forename: Vesna
authors.initials: V
authors.lastname: Zderic
authors.forename: Misty L
authors.initials: ML
authors.lastname: Noble
authors.forename: Jonathan C
authors.initials: JC
authors.lastname: Yuen
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Kaczkowski
authors.forename: Oleg A
authors.initials: OA
authors.lastname: Sapozhnikov
authors.forename: Francoise
authors.initials: F
authors.lastname: Chavrier
authors.forename: Lawrence A
authors.initials: LA
authors.lastname: Crum
authors.forename: Shahram
authors.initials: S
authors.lastname: Vaezy
mesh_terms: D000162:Acoustics; D000180:Acrylic Resins; D000818:Animals; D002138:Calibration; D002417:Cattle; D006801:Humans; D017711:Nonlinear Dynamics; D019047:Phantoms, Imaging; D012710:Serum Albumin, Bovine; D014159:Transducers; D036761:Ultrasound, High-Intensity Focused, Transrectal / Q000295:instrumentation / Q000379:methods
chemical_list: D000180:Acrylic Resins; C016680:polyacrylamide gels; D012710:Serum Albumin, Bovine